The Best Nonnutritive Sweetener

We dig through troves of research and decades of legislative battle to find the best nonnutritive sugar substitute, taking into account taste, safety, and overall effect on health.

Too busy to read the whole article? [4000+ words, a 20-minute read] Here are the takeaways:

  • There are two main types of low-calorie sweetener: sugar alcohols (polyols) and “nonnutritive” or “intense” sweeteners
  • I picked Splenda over dozens of other candidates because it’s readily available, easy to use, and has been thoroughly tested for safety.
  • Erythritol, a sugar alcohol, tastes more like sugar than any other alternative and has no measurable calories, but it’s a little pricey and could use some more testing for long-term effects.
  • Stevia has been widely praised for having health benefits, but mass-produced stevia in the U.S. is largely a processed chemical with questionable nutritional value. It’s hard to recommend any whole Stevia extracts in the U.S. without additional testing and research.
  • Looking at the bigger picture, the scientific community is still divided on whether replacing sugar with a nonnutritive sweetener actually helps prevent disease or manage weight, so if that’s your goal, you may want to consider a different strategy.

Here are some of the headlines that have been making the rounds about how much sugar we eat: Sugar is “toxic.”It’s more addictive than cocaine. It may be the real cause behind America’s obesity epidemic.

Read more about “natural” alternatives to sugar.

So are there any sugar substitutes worthy of buying? After looking at the five main nonnutritive sweeteners on the market as well as over a dozen less-known options, I came to strong conclusion:

The Best Nonnutritive Sugar Substitute:

Splenda (Sucralose)

$16 for the equivalent of 10 lbs

splenda

The best nonnutritive sweetener for most people is sucralose, often sold under the brand name Splenda. It’s easy to find, relatively cheap, tastes pretty good, and can be used in most cases just like sugar.

From a health standpoint, sucralose is the most widely-studied sweetener with the fewest reported negative effects. It has no significant calories and no measurable impact on metabolism.

There’s a chance that other sweeteners such as those derived from Stevia might some day trump sucralose, but for now, sucralose leads in all areas. I would particularly keep an eye on multi-sweetener blends, such as those containing erythritol, my runner up choice.

Also good, but needs sweetening help and more health research:

Erythritol

$20 for 2.5 lbs (equivalent to around 2lbs of sugar)

erythritol

Erythritol is a type of sugar alcohol or polyol. But, unlike most sugar alcohols, erythritol has no effective calories and none of the bowel problems caused by other sugar alcohols. With that being said, it’s also hard to get, expensive, and can cause intestinal discomfort and allergic reactions in some. It hasn’t been as carefully studied as sucralose, so while it seems very promising, I expect new research to come out as erythritol gains popularity.

Now that you know my conclusions, the rest of this article will be about how I tested and evaluated my research.

Nonutritive sweeteners have significantly fewer calories than normal sugar

When I researched all the “natural” alternatives to sugar, I found that there aren’t any great substitutes for plain white sugar, but that honey and brown rice syrup are worth trying in some cases. So, if other caloric sweeteners don’t hold the answer to the sugar controversy, will it help to try a nonutritive substitute? First, let’s talk about what these sweeteners are and how they came into being.

There are two types of sugar alternatives that contain fewer calories than sugar itself. Sugar alcohols or polyols are made from chemically-manipulated sugar molecules. Most polyols deliver fewer calories than sugar to achieve the same sweetening effect, though it depends on the particular polyol (more on that later). The other nonnutritive sweeteners are a family of “intense sweeteners” that may contain some calories, but that are so sweet, they make essentially no noticeable change to metabolism when used in reasonable amounts. Both intense sweeteners and polyols might be referred to as “artificial sweeteners.”

Sugar Alcohols: Hard-to-digest chemical cousins of sugar

You’re more likely to see the term “sugar alcohol” on a package than “polyol”, but I think “sugar alcohol” is somewhat of a misnomer. Sugar alcohols are so named because on one end, they look chemically similar to an alcohol (like ethanol), while on the other they resemble a standard saccahride. Since these chemical cousins of sugar don’t behave anything like alcohol, I think a much better name for the stuff is their other name, “polyol.” Here’s a breakdown of the polyols most often used as sugar substitutes:

Ingredient Sweetness Relative GI Cal/g
Sucrose 100% 1 4
Maltitol Syrup 75% .87 3
Hydrogenated Starch Hydrolysate 33% .65 2.8
Maltitol 75% .60 2.7
Xylitol 100% .22 2.5
Isomalt 55% .15 2.1
Sorbitol 60% .15 2.5
Lactitol 35% .10 2
Mannitol 60% 0 1.5
Erythritol 70% 0 0.2

[Table adapted from about.com]

Of these, the most commonly used are sorbitol, xylitol, and erythritol.

what happens when lactose-intolerant people drink milk? Same thing goes for eating too much polyol sweetener.

The common problem among most polyols is that they can cause intestinal distress. That’s because while we do possess the enzymes necessary to digest real sugars, we don’t have the enzymes necessary to digest polyols. The only way our guts can deal with them is through bacterial fermentation. And when we digest food through fermentation, the result can be pain, diarrhea, and gas.

Think about it this way: what happens when lactose-intolerant people drink milk? Same thing goes for eating too much polyol sweetener.

But erythritol might be the one shining star in this family of sweeteners

Here are the facts about erythritol:

  • Erythritol is around 70% as sweet as sugar with practically zero caloric impact.
  • When fed to healthy adults, erythritol had no impact on insulin or other important hormones that are usually driven up by sugar intake.1, 2
  • That’s probably because about 80% of ingested erythritol is excreted without being metabolized.3, 4
  • Then what about all that erythritol that floats in your blood stream? Short-term human studies showed minimal effects.5, 6
  • And long-term animal studies haven’t shown any evidence of toxicity.7, 8
  • There have been a few reported cases of allergic reaction to erythritol. The number now is few, though it’s unknown whether reactions would increase if erythritol became more popular.9, 10, 11

For all these reasons, I would easily classify erythritol as the most promising of the sugar alcohols/polyols, though the allergic reactions currently reported should be more carefully studied.

Nonnutritive Sweeteners

Nonnutritive sweeteners are sweeteners that essentially contribute no measurable addition to energy intake (calories) when used in normal amounts. That’s because most of these compounds are many hundreds of times sweeter than sugar. You use so little to get the desired level of sweetness, the calories don’t matter.

When considering the nutrition of nonnutritive sweeteners, you need to ask two questions: (1) is it safe? and (2) is it better for me than sugar?

Is it Safe?

The Food and Drug Administration of the United States recognizes several nonnutritive sweeteners as “Generally Recognized as Safe” or GRAS. These include Aspartame, Saccharin, Sucralose, Acesulfame Potassium (Acesulfame K), and Neotame. In the case of sweeteners, the public is actually benefiting from the powers of large corporations. The nonnutritive sweetener companies want the government to label their products safe, but sugar producers would love to see all these sweeteners banned. The result is that the FDA has been able to analyze troves of research on both sides of the debate.

I drew most of my conclusions from these already well-documented controversies.

Aspartame

First introduced in 1974, then banned over concerns about brain damage. In 2007, a review of existing research on Aspartame concluded that “the weight of existing evidence is that aspartame is safe at current levels of consumption as a nonnutritive sweetener.”12. The argument from the anti-aspartame side would qualify, though, that most studies on Aspartame have been funded or influenced by corporations, so review studies such as the 2007 one are invalid to begin with.13

Aspartame is the most controversial and potentially most dangerous sweetener of all the nonnutritive sweeteners.

The FDA does recognize that people sensitive to phenylalanine may be intolerant of aspartame (aspartame breaks down in the body into aspartic acid and phenylalanine). A 2008 study also illustrated the dangers of aspartame to the brain 14 The most recent research I could find on aspartame dates to 2014 call for an “urgent review” of existing carcinogenic studies. Aspartame is the most controversial and potentially most dangerous sweetener of all the nonnutritive sweeteners. 15

Saccharin

Saccharin is the oldest of the nonnutritive sweeteners and is considered one of the most studied. Today, it is considered safe for human consumption, but has waned in popularity in recent years due to its bitter aftertaste. The best known brand of commercial saccharin is Sweet ‘n Low. Saccharin was the subject of considerable controversy in the 1970s. Studies showed that it was responsible for causing cancer in rats. There were many powerful companies interested in weighing in on the debate. The key players were producers of saccharin and the sugar lobby, as well as the producer of aspartame, then the biggest competitor to saccharin in the nonnutritive sweetener space.

Several studies of saccharin in rats associated saccharin consumption with the development of bladder cancer. 16, 17, 18, However, later studies showed that rats digest saccharin in a way not relevant to humans and the FDA subsequently removed warning labels that saccharin may be a carcinogen.19 By the early 2000s, the consensus of the food science community was that although saccharin does indeed cause bladder in rats, it does no harm in humans.20

Sucralose

Several health experts claim that isolated patients have had allergic reactions to Splenda, but the only two references I found to reactions were two papers from 2006 that identified two single instances of sucralose being linked to migraines.21 The widely-propagated notion that Splenda was approved by the FDA as safe without proper testing also seems ill-founded, as multiple sources claim the FDA reviewed over 100 studies before giving sucralose approval.22, 23, 24 One recent review called sucralose “one of the most researched and reviewed food additives today.”25

Sucralose and Gut Health

A recent study that received attention in health- and natural-food circles found that sucralose negatively altered the gut flora of rats26, but a later expert review of that study concluded that it was not “scientifically valid.”27 Concerns had also been raised the rat study was funded in part by the Sugar Association.28 Although the matter seemed to remain of some debate, I have been unable to find any follow-on research from the original researchers and more recent research on Splenda in the human gut has found no significant negative effects.

However, based on my personal experience sucralose does cause digestive issues. I have symptoms of SIBO, or small intestinal bacterial overgrowth, intermittently. After taking preworkouts or drinks with this sweetener, I notice symptoms of SIBO within hours, which persist for 24 to 48 hours until the sucralose has passed through my system. And it’s not just me. Several sites listing what not to eat for SIBO and low FODMAPS diets include sucralose, or Splenda, on their “stay away” lists.

Acesulfame Potassium and Neotame

Both Acesulfame Potassium and Neotame are more likely to be found in your diet coke than on store shelves. For that reason, it appears that they have less often been the subject of scientific investigation. Acesulfame potassium was approved in the 1980s as a food additive, but it was less-often used due to a bitter aftertaste. In recent years, it’s come back into favor because it can be mixed with other sweeteners to produce a desirable taste. I couldn’t find comprehensive review articles about Acesulfame potassium, though several sources have called for more thorough carcinogenic testing.29

Neotame is in a similar boat with acesulfame: neotame is a modified version of aspartame. Like the other nonnutritives covered here, there are plenty of sources that claim neotame is safe and has been well-tested, but I am reluctant to recommend it without seeing more debate and research on the sweetener. Neotame is still not popular both for retail sales and in the industry due to its poor aftertaste.

Stevia

When I started researching this article, I genuinely thought that I would be giving the crown to stevia. In recent years, stevia, or more precisely the concentrated extract of the Stevia rebaudiana plant has become the darling of natural-food enthusiasts looking for a safe, healthy alternative to sugar.

Here are the arguments in favor of stevia:

  • Stevia is extracted from a plant. All the other nonnutritive sweeteners are synthesized in a lab.
  • Many cultures have used stevia as a natural sweetener. Studies dating back to the 1970s have shown that stevia is safe for human consumption.
  • In Japan, over 40,000 clinical trials have been conducted on stevia, the vast majority of which demonstrate that stevia is safe for consumption.
  • In fact, it’s not just safe, stevia has been suggested as a treatment for diabetes, a way to lower blood pressure, and for its antioxidant properties.30

So if all this is true, why don’t I think stevia should be crowned the best nonnutritive sweetener?

Look closely at the labels of any major stevia product on the market today. You’ll notice the ingredients will list something like “Reb A (Stevia extract)” and in many cases, erythritol. Reb A is short for Rebaudioside A, a processed extract of the stevia plant considered its most sweet constituent with the least bitter aftertaste. Comparing Rebaudioside A to stevia extract would be like comparing processed fructose to natural honey. Honey has been shown to have many beneficial effects on human health, but those benefits depend heavily on the sourcing and processing of the honey. I’m not trying to say that Rebaudioside A is as bad for you as processed fructose would be, but saying that a product containing Rebaudioside A has the same health benefits as stevia extract proof would be flat wrong.

As for erythritol? I’ve already written about erythritol’s use as a sweetener, above. It’s a solid alternative to sugar and the addition of Reb A probably makes it a little sweeter without adding any negative side effects. But I don’t think the erythritol and Reb A combination edges out sucralose’s advantages.

saying that a product containing Rebaudioside A has the same health benefits as stevia extract proof would be flat wrong.

As for Stevia, the extract? I have a few bottles of stevia in my pantry and I do use them from time to time, usually to add sweetness to a product I’ve already sweetened with something else. The few extracts I’ve tried have all had a noticeable bitter aftertaste in any quantity.

More importantly, stevia extract is not technically approved by the FDA as generally recognized as safe (GRAS). And there’s a good reason for that. It’s perfectly acceptable to market stevia extract as a supplement, but it’d be very difficult to get a plant extract approved as a general-purpose sweetener. All the trace amounts of compounds that might have health benefits could also potentially cause harm if manufacturers don’t understand and control them properly.

Consider this line from a review of Stevia’s use and health effects: according to Japanese researchers, “a sign of an excellent Stevia product is one that is free of this liquorice essence and still not bitter.”31 A quote like that raises the question: what exactly constitutes a “high-quality” stevia extract? Might some extracts be a true miracle sweetener while others have toxic effects?

I simply don’t think we have enough research and public awareness of how stevia extracts sold in the United States are extracted and processed to make a firm recommendation either way.

Even if they are safe, nonnutritive sweeteners may not be healthier than sugar

I’ve focused on safety, but assuming whatever nonnutritive sweetener is safe, is it still better for you than sugar?

Here are the basic arguments against the overconsumption of sugar:

  1. Sugar has a considerable amount of calories with no significant nutritional (micronutrient/vitamin) content.
  2. Sugar is digested quickly, which means it places a glycemic load on our bodies, which can lead to insulin resistance and metabolic syndrome, which is in turn linked to obesity, heart disease, and type 2 diabetes.
  3. Since it’s sweet, we tend to eat too much sugar, and that can cause us to overeat other foods, ultimately leading to weight gain.

By definition, nonnutritive sweeteners have negligible calories, so studies have focused on (1) whether nonnutritive sweeteners elicit an insulin response similar to sugar and (2) whether replacing sugar with nonnutritive sweeteners results in long-term weight loss.

The results, unfortunately, have not been promising.

Long-term epidemiologic reviews of existing populations have found that the consumption of nonnutritive sweeteners (specifically in the form of diet sodas) actually increases weight gain32, 33 and increased risk of developing metabolic syndrome and type 2 diabetes.34, 35

While these studies have been quick to point out that they merely establish association and can’t comment on causation without further research, the results are nonetheless disappointing for people who might be considering switching from sugar-sweetened beverages to diet sodas as a means of improving health.

But, in the short term, studies show a contradictory result.

Study after study shows that, compared to sucrose, nonnutritive sweeteners have less effect on glucose levels, insulin response, and other hormones related to insulin resistance.36

Some human studies have shown that replacing low-nutritional-value sweetened beverages with artificially-sweetened beverages can support weight control37, 38,but the American Diabetes Association and American Heart Association together concluded as of 2012 that there hadn’t been enough trials conducted to make a conclusive recommendation one way or another.39

Now, I could go through each of the nonnutritive sweeteners I’ve written about and try to piece together each compound’s specific metabolic impact and long-term effects, but much of the evidence in this field of research looks more at questions of how we perceive food and the other foods we choose to eat when we drink sweetened beverages. The specific chemical behavior of particular sweeteners may not be the most important factor here.

So, should I be using a sugar substitute?

Yeah, I think so.

Here’s why: I have a big bag of Splenda sitting in my pantry right now (as well as a whole lot of other sweeteners—had to be thorough in my testing) and I plan to keep it there. But using splenda is not my strategy for preventing diabetes and managing my weight. To do that, I limit my overall intake of simple carbohydrates, eat vegetables with high nutritional value, and exercise, among other things.

I keep sucralose around because sometimes I like to make lemonade in the summer and it tastes pretty good with a spoonful of splenda in it. I don’t like the way I personally feel after drinking sugar-sweetened beverages, so if I am craving a sweetened beverage, I’ll pick a small dose of splenda over an equivalent amount of sugar.

If you can completely avoid sweetened foods and beverages, then by all means skip buying any sweetener, be it caloric or nonnutritive. But if you’re looking for a well-priced, easy-to-use option, for now, sucralose looks like your best bet, just don’t rely on a sugar substitute as your best means of staying healthy.

Have you ever tried a sugar substitute? Tell me about it in the comments!

Liked this article? Make sure to check out my piece on “natural” sugar alternatives.

Notes:

  1. Noda K, Nakayama K, Oku T (1994). Serum glucose and insulin levels and erythritol balance after oral administration of erythritol in healthy subjects.European journal of clinical nutrition 48(4), 286-292
  2. Bornet, F. R. J, et al. (1996). Gastrointestinal response and plasma and urine determinations in human subjects given erythritol Regulatory Toxicology and Pharmacology 24(2), 296-302.
  3. Arrigoni, E, Fbrouns, F, Amado, R (2005). Human gut microbiota does not ferment erythritol British Journal of Nutrition 94(5), 643-646
  4. Tetzloff W, et al. (1996). Tolerance to subchronic, high-dose ingestion of erythritol in human volunteers Regulatory toxicology and pharmacology 24(2), 286-295
  5. Tetzloff W, et al. (1996). Tolerance to subchronic, high-dose ingestion of erythritol in human volunteers Regulatory toxicology and pharmacology 24(2), 286-295
  6. Oku, Tsuneyuki, Mitsuko Okazaki (1996). Laxative threshold of sugar alcohol erythritol in human subjects Nutrition Research 16(4), 577-589
  7. Lina, B. A. R, et al. (1996). Chronic toxicity and carcinogenicity study of erythritol in rats Regulatory toxicology and pharmacology 24(2), 264-279
  8. Munro, I. C, et al. (1998). Erythritol: an interpretive summary of biochemical, metabolic, toxicological and clinical data Food and Chemical Toxicology 36(12), 1139-1174
  9. Hino, Haruko, et al. (2000). A case of allergic urticaria caused by erythritol The Journal of dermatology 27(3), 163-165
  10. Shirao, Kenichiro, et al. (2013). Bitter Sweet”: A Child Case of Erythritol-Induced Anaphylaxis Allergology international: official journal of the Japanese Society of Allergology 62(2), 269-271
  11. Abou-Donia, M. B., et al. (2008). Splenda alters gut microflora and increases intestinal p-glycoprotein and cytochrome p-450 in male rats. Journal of Toxicology and Environmental Health 71(21), 1415-1429
  12. Magnuson, B. A, et al. (2007). Aspartame: a safety evaluation based on current use levels, regulations, and toxicological and epidemiological studies CRC Critical Reviews in Toxicology 37(8), 629-727
  13. Mercola.com (2010). Aspartame’s Dangers, Side Effects and FDA Approval Explained Mercola.com.
  14. Humphries, P, E. Pretorius, H. Naude (2008). Direct and indirect cellular effects of aspartame on the brain European journal of clinical nutrition 62(4), 451-462
  15. Soffritti, Morando, et al. (2014). The carcinogenic effects of aspartame: The urgent need for regulatory re‐evaluation American journal of industrial medicine.
  16. Munro, I. C, et al. (1975). A carcinogenicity study of commercial saccharin in the rat Toxicology and applied pharmacology 32(3), 513-526
  17. Price, J. M, et al. (1970). Bladder tumors in rats fed cyclohexylamine or high doses of a mixture of cyclamate and saccharin Science 167(3921), 1131-1132
  18. Cohen, Samuel M, et al. (1979). Promoting effect of saccharin and DL-tryptophan in urinary bladder carcinogenesis Cancer research 39(4), 1207-1217
  19. Integrated Laboratory Systems (1999). NTP Report on Carcinogens Background Document for Saccharin.
  20. Singh, Zorawar (2013). Toxicological Aspects of Saccharin Food Biology 2(1), pg 4.
  21. Patel, Rajendrakumar M, Rakesh Sarma, Edwin Grimsley (2006). Popular sweetner sucralose as a migraine trigger Headache: The Journal of Head and Face Pain 46(8), 1303-1304.
  22. Rodero, A. B.; Rodero, L. S.; Azoubel, R. (2009). “Toxicity of sucralose in humans: a review. Int J Morph. 21(1), 239-244.
  23. Grotz, V. Lee, Ian C. Munro (2009). An overview of the safety of sucralose Regulatory toxicology and pharmacology 55(1), 1-5.
  24. Grice HC; Goldsmith LA (2000). “Sucralose–an overview of the toxicity data”. Food Chem Toxicol 38 (Suppl 2): S1–6.
  25. Shankar, Padmini, Suman Ahuja, Krishnan Sriram (2013). Non-nutritive sweeteners: Review and update Nutrition 29(11), 1293-1299.
  26. Abou-Donia, M. B., et al. (2008). Splenda alters gut microflora and increases intestinal p-glycoprotein and cytochrome p-450 in male rats. Journal of Toxicology and Environmental Health 71(21), 1415-1429.
  27. Brusick, David, et al. (2009). Expert panel report on a study of Splenda in male rats Regulatory Toxicology and Pharmacology 55(1), 6.
  28. Daniells, S. (2008). Splenda study: Industry and acadmemia respond FoodNavigator.com.
  29. Karstadt, Myra (2010). Inadequate toxicity tests of food additive acesulfame International journal of occupational and environmental health 16(1), 89-96.
  30. All these conclusions are drawn from the excellent review paper Goyal, S. K, R. K. Goyal (2010). Stevia (Stevia rebaudiana) a bio-sweetener: a review. It cites dozens of other references, some of which I couldn’t find in databases I have access to, so I’ve just cited the review here.
  31. Goyal, S. K, R. K. Goyal (2010). Stevia (Stevia rebaudiana) a bio-sweetener: a review.
  32. Fowler, Sharon P, et al. (2008). Fueling the Obesity Epidemic? Artificially Sweetened Beverage Use and Long‐term Weight Gain Obesity 16(8), 1894-1900.
  33. Stellman, Steven D, Lawrence Garfinkel (1986). Artificial sweetener use and one-year weight change among women Preventive medicine 15(2), 195-202.
  34. Nettleton, Jennifer A, et al. (2009). Diet soda intake and risk of incident metabolic syndrome and type 2 diabetes in the Multi-Ethnic Study of Atherosclerosis (MESA). Diabetes 32(4), 688-694.
  35. Fagherazzi, Guy, et al. (2013). Consumption of artificially and sugar-sweetened beverages and incident type 2 diabetes in the Etude Epidémiologique auprès des femmes de la Mutuelle Générale de l’Education Nationale–European Prospective Investigation into Cancer and Nutrition cohort The American journal of clinical nutrition 97(3), 517-523.
  36. As summarized in Shankar, Padmini, Suman Ahuja, Krishnan Sriram (2013). Non-nutritive sweeteners: Review and update Nutrition 29(11), 1293-1299.
  37. de Ruyter, Janne C., et al. (2012). A trial of sugar-free or sugar-sweetened beverages and body weight in children New England Journal of Medicine 367(15), 1397-1406.
  38. Sørensen, Lone B., et al. (2014). Sucrose compared with artificial sweeteners: a clinical intervention study of effects on energy intake, appetite, and energy expenditure after 10 wk of supplementation in overweight subjects The American journal of clinical nutrition.
  39. Gardner, C, et al. (2012). Nonnutritive Sweeteners: Current Use and Health Perspectives Diabetes Care 35(8), 1798-1808.

The Science of Great Sleep

Too busy to read the whole article? [4,500 words, a 23-minute read] Here are the key takeaways:

  • Try to sleep 7-8 hours a night.
  • If you sleep better, you’ll be better at regulating emotions, remembering things, working out, and not overeating.
  • To get a better night’s sleep: (1) exercise (2) don’t drink before bed (3) keep your bedroom lights dim (4) avoid gadgets with a screen (5) find a comfortable pillow and (6) try sleeping on your right side.
  • Benadryl and Unisom can help you fall asleep every once in a while, but herbal supplements haven’t been very effective in trials.
  • Artificial dawn alarms can help you feel less sleepy in the morning. But, snoozing any alarm is probably a bad idea.
  • If you didn’t get enough sleep, try a 10-minute nap, a cup of coffee, stretching, or taking a walk.

Tytus Wilson, 27, an entrepreneur in Louisville, Ky estimates he’s spent over $20,000 over the last three years on products to help him track and improve his health. Sleep is a big part of that.

He’s experimented with things like blue light-blocking glasses, a grounding blanket that directs electrons from the earth into the human body, and magnesium supplements to improve his sleep. He’s also tracked the impact of diet, moods and daily steps on his sleep.

He says he realizes some of it sounds ridiculous.“I don’t spend any money on houses, cars and furniture,” he says. “If somebody tells me ‘This will help your sleep.’ I don’t care what it is, I’ll try it and see what happens.”

Wilson is probably an outlier, but sleep is a big concern among millennials. 43%  rated their sleep quality as “fair or poor” in an American Psychological Association poll. We’re more likely than older generations to stress about sleep quality too. 1

Robin Haight, a clinical psychologist in Tyson’s Corner, Va. attributes that stress in part to the internet. “Millennials have more access to information about wellness and health than perhaps older generations had at that same age,” she says. Even at 3 AM—when you’re lying awake in bed, you can go online and find articles citing research that links lack of sleep with things like decreased vaccine effectiveness2 and increased risk for Alzheimer’s Disease.3Haight adds that the increase in research and awareness about sleep can be a good thing, though.

Ever wondered how your sleep compares to everyone else’s? Here’s what a “normal” night’s sleep might look like in healthy 20-somethings:

  • Time to fall asleep: 6.3 minutes
  • Time spent in bed vs. time asleep (sleep efficiency): 6.6 hours to 6.2 hours (94%)
  • Awakenings per hour: 1
  • % of night spent in non-REM sleep: 72.3%
  • % of night spent in REM sleep: 22.2%

reference:4

Is a good night’s sleep really that important?

Here are some of the ways sleeping better makes life more pleasant:

Sleep helps keep you from freaking out about the small stuff. Brain scans taken when sleep-deprived people viewed photos with negative subject matter showed more activation in the amygdala (a part of the brain involved in emotional reaction)5 than in people who’d slept normally. The sleep-deprived people also had a loss of connection between the amygdala and the medial prefrontal cortex, a part of the brain that can help moderate emotional reactions.6,7

To put that in a context that’s closer to real life, people in a study who had their sleep cut by 33% for an entire week reported mental fatigue and emotional instability that worsened over the week.8

Sleep is also good for your memory. A research review cites 35 studies that link inadequate sleep with declines in memory encoding (creating new memories) and memory consolidation (incorporating new memories into long-term memory).  Many of the studies found that people were better able to remember things like a string of letters or solutions to math problems after a night’s sleep.9

Sleep can help you get the most out of your workout. Sleep deprivation can significantly decrease your reaction time, which is important in activities like team sports or weightlifting.10

In another study, players on the Stanford University men’s basketball team improved their shooting accuracy, sprinted faster and reported feeling better overall during games after 5-7 weeks of increased sleep.11

New York-based Hannah Jiang, 23 says sleeping well helps her in her running, biking and other cardio workouts. “If I get the perfect amount [of sleep] like 8 hours and I’m eating well, and I’m working out well, everything is just better. My attitude is better too,” she says.

Sleep can help prevent weight gain. A handful of studies have found an association between shorter sleep hours and obesity. Possible explanations for the correlation: increased calorie intake due to more production of  hunger hormone ghrelin and less production of satiety hormone leptin. Or more available hours in the day to eat. You can’t munch at midnight if you’re not awake. Another explanation: sleep-induced fatigue or reduced ability to regulate body temperature could make working out a lot less appealing.12

In one study, people stayed in a sleep lab for 14 days and were allowed to sleep either 5.5 hours a night or 8.5 hours, the 5.5 hour group ate more snacks, on top of regular meals.13

Beauty sleep might be a real thing. Viewers perceived photos of people who’d slept well as more attractive and healthier looking than photos of the same people who hadn’t slept for a night.14

Now that we’ve established why better sleep is a good idea, let’s talk about the nitty gritty of how to actually sleep better.

Better sleep: What should you do throughout the day?

Make your bed in the morning. Jiang says she tries to as part of her strategy to keep her bedroom uncluttered.  “I try to make [my bedroom] as sort of zen-like as possible—otherwise I find that my mind is all over the place,” she says. “If I have stuff from work that I bring home, I try not to do it in bed because I find that I’m thinking about it.”

She may be on to something. Maybe it’s the old adage that a clean room leads to a clear mind. Or maybe well-made beds just look more inviting. Either way, research shows that people who make their beds every or almost every day are more likely to sleep better at night (though this is at best correlation, not causation).15

Exercise. Remember that better sleep can help you be a better exerciser? It can work the other way too, says Max Hirshkowitz, a professor at Baylor College of Medicine. “If you think of what we call the three pillars of health, which is diet, exercise and sleep, any one of those can improve the others,” he says.

A good reason to step up your workout: in a poll by the National Sleep Foundation, vigorous exercisers (runners, cyclists, swimmers and competitive sports players) reported falling asleep more easily, staying asleep all night, and waking up refreshed more often than people who do less intense workouts. But don’t give up on yoga or walking yet. Moderate and light exercisers said they have better sleep than people who don’t work out at all.

Hirshkowitz, lead advisor on the poll, doesn’t know the reason behind this, but hard workouts may also act as a buffer against bad sleep. Vigorous exercisers reported less impairment in their work, social and sex lives when they didn’t get adequate sleep.16

If you already exercise, but want to try to improve your routine for maximum sleep benefit, Hirshkowitz recommends exercises that improve conditioning as opposed to strength.  “If you’re running, I would say run a little faster, but maybe further to increase conditioning. If you’re doing weights, I would say doing more reps,” he says. He emphasizes building your routine gradually, as injuries can wreck your sleep and undo any benefits.

Cocktails at happy hour and nightcaps might not be a great idea. “Most people kind of believe that [alcohol] helps you sleep and no one’s been able to actually prove that in a lab,” says Eliza Van Reen, a professor of psychiatry and human behavior at Brown University. Her experiments indicate that just one drink can mess with your sleep. Participants who had a vodka tonic around 4 PM17 as well as at 9:30 PM18 had more difficulty getting to sleep than those who had a placebo.

But maybe you remember a time where you’ve had a few drinks and gone to sleep with no trouble. A review of 80 years of research (conducted between the 1920s-2010s) on alcohol and “normal” sleepers found that low (1-2 drinks), moderate (2-4 drinks) and high (4+ drinks) doses of alcohol tended to decrease the time it took to fall asleep. However, moderate and high doses caused a reduction in deeper, restorative REM sleep.19

Get out. Psychologist Robin Haight recommends getting outside for at least 15-20 minutes each day. “Being indoors for the majority of the day can actually interfere with the sleep-wake cycle,” she says. Sunlight exposure jumpstarts the body’s production of melatonin, the hormone most responsible for the regulation of sleep cycles.20

Better sleep: The critical hour before bed

On average, millennials go to bed around 11:58 PM.21 So let’s say it’s 10:58 p.m. Maybe you’re sleepy, maybe you’re not, but you know you should go to bed soon. Now is a good time to turn down the lights.

In dim light, melatonin can start doing its work over an hour earlier than in normal room light.22 How dim should your room be? Researcher Joshua Gooley says you should still be able to read a book, but that the fine print might be difficult. To achieve the ideal pre-sleep lighting level, Gooley recommends using a bedside lamp or putting a dimmer on overhead lights.

After making sure you’ve got sufficiently dim light in the bedroom, pay attention to your bathroom light. If you take a shower at night, or spend any other amount of time in there, bright white light can end that peaceful, sleepy feeling created by a dim bedroom. Warmer, or more yellow light (or a dimmer on the white light) is less jolting.23

Get rid of anything with a screen. The relatively bluer light from computer and tablet screens can interfere with melatonin production more than any other type of light.24There’s no clear answer on how much blue light exposure it takes to suppress melatonin. One study says 5 hours.25 Another says 1-2.26 A general guideline is to avoid bright screens 2-3 hours before bed.27Or, if you absolutely can’t do that, try blue light-blocking glasses or programs that change the color of your screens.

Besides the light factor, there’s the distraction of having a device right by your side that you can use to communicate with anyone, at any time. 67% of 19-29-year-olds say they take their phones to bed.28 Not surprising, right? If anything, that percentage seems a little low.

The most popular use of the cell phone in bed? Texting. Unfortunately, people who text in the hour before bed every night or almost every night are less likely to say they get good sleep, and more likely to be classified as “sleepy” on the Epworth Sleepiness Scale.29

If you absolutely have to take your phone or iPad to bed with you (and I’m guessing you are—habits die hard) turn the brightness down and hold it at least 14 inches away from your face. This reduces the brightness to a level that doesn’t mess with melatonin production as much.30 Airplane mode is probably a good idea too.

Better sleep: Sleep environment (your bed and bedroom) matters

So what exactly is a comfortable bedroom environment? 25-34-year-olds said in a National Sleep Foundation Poll that the top three environmental factors in their are: pillows, bedroom darkness and bedroom temperature, in that order.31

Pillows

If the importance of pillows inspires you to go shopping, be prepared to be overwhelmed. On Amazon alone, there are 11,210 results for “pillow” in the “Health & Personal Care” category.

There’s pretty much no objective way to define a “good” pillow. One study recommended a pillow with an indentation to support the neck for people who tend to sleep on their back or side. 32 Another found that rubber pillows got high marks for general comfort.33 Another said anything but feather pillows.34

To save you some time, (and possibly money by preventing a bad purchase) Nick Robinson, creator of the website Sleep Like the Dead aggregated more than 21,000 consumer reviews from sites like Amazon and Overstock into a table that scores nine types of pillows in 21 categories.35

For example, if you wanted to find a pillow that online reviewers says reduces pain or is good for sleeping on your stomach, the table can point you to a category of pillow (say, a down alternative) and then towards a specific brand.

Darkness

I already wrote about the importance of dimming lights and expelling gadgets from the bedroom. I’ll just add here that if you have problems with light at night (like a streetlamp shining in your window, or some other non-controllable factor) light-blocking curtains are a lifesaver. Insulated thermal panel curtains from Overstock get high scores by reviewers. My personal recommendation: stylish velvet light-blocking curtains from Target.

A light-blocking sleep mask is a cheaper, more portable option. Online reviewers like the Prime Effects sleep mask that has attached earplugs.

Temperature

If you like to sleep with typical blankets, the ideal sleep temperature appears to be between 60.8 and 66.2 degrees at night. If you’re the rare person that sleeps naked with no covers, something like 86-89.6 degrees is better. And if you sleep with just a sheet over yourself, you’ll probably be best off somewhere in between.36

If you sleep with a partner, there’s always a chance that no amount of thermostat adjusting will make you both happy. One interesting option: regulating mattress temperature. The ChiliPad and the Outlast mattress pad both go over your existing mattress and use different technologies to adjust temperature for hot and cold sleepers.

If spending hundreds of dollars on a fancy mattress pad isn’t your idea of a good investment, hot sleepers could consider using a fan for a stream of cool air. And cold sleepers always have the option of more clothing or blankets.

The fastest ways to get to sleep

Now for the main event: falling and staying asleep.

The average amount of time it takes to fall asleep is 6.3 minutes, but anything less than 15 minutes is good.37If you’re still lying awake after that,  here are two interesting techniques I found.

Progressive relaxation. Basically, it’s going through your entire body, from your forehead to your toes, tensing each muscle one-by-one, then releasing that tension.38 There are countless  videos that will guide you through this process. Yoga teacher Jodie Tingle-Willis, says it’s important to find a video with a pleasing voice. “I might like an Australian accent, but it might drive you crazy,” she says.

One study found that progressive relaxation was very effective in helping people with multiple sclerosis get to sleep39 and another found that progressive relaxation can be as effective as Valium in reducing brain activity during a stressful state.40 Unfortunately, I didn’t find any tests of the effectiveness of progressive relaxation for sleep in people who weren’t suffering from chronic conditions.

The “cognitive shuffle.” We’ve all been there: maybe you’re worried about what you have to do tomorrow, or what you did today. All of the sudden, you feel like you’re stuck in an endless loop of thoughts. There’s an app that can help stop that loop—as long as you’re going to take your phone to bed despite some researchers’ advice not to. The idea behind mySleepButton is to take your mind off your worries by guiding you through a series of random images like, “a canoe, playing golf, holding a paper cup.”  (41) 41

Body position is one of the less-discussed aspects of sleep. Joseph De Koninck isa psychology professor at the University of Ottawa researches sleep and dreams. He says that younger adults tend to change position about 30 times per night. When he filmed people for two nights in a sleep lab, he found that “good sleepers,” or people who are normally satisfied with their sleep, changed position less than people who weren’t satisfied.

The good sleeper group also spent more time lying on their right side with their arms and legs both folded. Poor sleepers spent a lot of time on their back.42

Although none of the participants in his study had a sleep disorder, De Koninck says back sleeping is also associated with sleep apnea. If you’re healthy and don’t have any trouble sleeping, De Koninck says there’s no reason to change your sleep position. But if you do want to sleep on your back less, he mentioned devices like the Zzoma—a belt with a pillow attached to the back to make it more comfortable to rest on your side and less comfortable to lay on your back.

Interesting side note: another, more recent study found that right-side sleepers got better scores on the Pittsburgh Sleep Quality Index and had fewer nightmares than left-side sleepers.43

Focus on rest, not sleep. “I always advise people to never look at the alarm clock, never look at the phone. It doesn’t help to know what time it is. It doesn’t help to know how long you’ve been awake. It’s just going to make you stress out,” says Robin Haight. “Just know that your body is resting, even if you aren’t sleeping.”

In one study, participants were challenged to fall asleep as quickly as possible, with a monetary reward attached. But of course the challenge group ended up getting less and worse sleep than the control group, who simply went to sleep with no instructions.44

Sleep supplements. I can’t ignore supplements when writing about sleep. But, this is a HUGE topic. For the sake of not making this article a million words long, I stuck to over-the-counter supplements. This definitely isn’t an exhaustive list, but here are some I ran across, and briefly and what published research says about them:

  • Diphenhydramine, the active ingredient in Benadryl, can work for occasional trouble falling asleep. But its effectiveness wears off pretty quickly with repeated use.45
  • Same with doxylamine, the ingredient in Unisom.46
  • Melatonin supplements might help you fall asleep, but they’re not a surefire shot at a good night’s sleep.47 Oddly, one study found that melatonin found naturally in cherry juice was helpful for sleep.48
  • Valerian, an herb sold in capsule form, doesn’t really do much.49
  • Tryptophan, an amino acid, can be effective.50 Even small amounts can be effective, such as the levels found in foods like turkey and pumpkin seeds.51
  • Finally, a magnesium supplement can be effective if you have a deficiency52 but the effects have mostly been studied in adults over 50.53

My summary: this is only what some of the research says. There’s a lot more out there about all these substances. If you’re interested in one, do some more reading on your own.

Better sleep: how much is enough?

“If you always need an alarm clock to wake up, you’re probably not getting enough sleep.”

Once you’re asleep, how long should you stay there? 6.6 hours in bed is the norm, but that might not be enough. 25-34-year olds say they’d like to get 7.4 hours to function and feel best.54

Elizabeth Klerman, a professor at Harvard Medical School’s Division of Sleep Medicine, who’s studied sleep variation found that when given the opportunity to sleep more hours, people will do it. In one of her studies, people who reported a baseline of 6.1-10.3 hours of sleep per night slept an average of 4.9 hours more when they were allowed to. The participants with a higher baseline of sleep leveled off after a few days, but the people more towards the 6.1 end continued to sleep more hours. (51) Klerman says this suggests that a lot of people are walking around with a sleep debt and they don’t realize it.

Klerman’s advice: “If you always need an alarm clock to wake up, you’re probably not getting enough sleep.”

Waking Up

Oh, hey, it’s been 8 hours. Or 6. Or whatever. It’s time to get up!

Unless you got your magic number of sleep hours, you’re probably feeling groggy and maybe fumbling around as you start your morning routine. That feeling is called sleep inertia. It’s the time between the alarm going off and when you feel fully awake and it can last from a few minutes to a couple hours.55

The only way to not experience this feeling is to wake up naturally, with no alarm clock.56 Of course, if that’s not possible, an artificial dawn light might help. 18-36-year-olds who had trouble waking up at least 4 days a week, said the light helped them feel less sleepy and more active after using the light for 30 minutes before the alarm went off. 57

The Sleep Cycle app is something else you can try to cut down on that feeling of sleep inertia. You set the alarm on it for the time you want to wake up, say 7 a.m. It uses the accelerator on your phone to sense movement during the night. According to the product description, you move differently in every phase of sleep, so Sleep Cycle will use that movement to wake you up when you’re in the lightest phase of sleep at some point between 6:30 and 7.58

I didn’t find any studies that put Sleep Cycle to the test, but Fitbit data analyst Naveen Sinha, 29, says he relies on it. Tytus Wilson has also used the app since 2009. “I noticed that it was good at waking me up in that already restless time. I would just hear the ding and be ready to go,” he says.

Regardless of the type of alarm you use, try not to hit snooze. I didn’t find any peer-reviewed research that specifically says not to, but I did find these two solid arguments:

  • When you hit snooze, your body restarts the sleep cycle, making you more and more sleepy each time your alarm goes off59
  • If you’re snoozing for 20 to 30 minutes anyway, why not set y0ur alarm later and just get solid, uninterrupted sleep?60

So just get out of bed, already! That sounds easy until it’s actually time to do it, right? To really get yourself going in the morning, try one of these highly motivational alarm clocks. One forces you to stand up on your feet, one is a weight that makes you do 30 reps and another connects to your bank account, then makes a donation each time you hit snooze.61

What to do after a bad night’s sleep

Occasionally (well, hopefully occasionally), everyone has a night where they only get a few hours of sleep. Here’s what you can do to survive those sleep-deprived days.

Two obvious solutions are caffeine and naps. But which one works better?  Actually, they’re both about the same, according to one study that compared signs of afternoon sleepiness after a 20-minute nap or two cups of coffee containing 150 mg of caffeine. Measures of sleepiness went down a little, but not really that much. Then again, this study only tested participants who had slept normally the night before.62

After a night of sleep restriction (to 4.7 and 5 hours), two studies found that a 10-minute nap decreased feelings of sleepiness and improved cognitive performance.63 64 Another study showed that 100 mg of caffeine (in pill form) improved performance on a grammatical reasoning test and lessened feelings of sleepiness. Caffeine didn’t beat a placebo on a test of alertness and reaction time.65

If you’re worried about overall caffeine intake, even a placebo might help. Two groups of people in one study each had one cup of decaffeinated coffee. Researchers told one group that their coffee was caffeinated. The group who thought they’d consumed caffeine had quicker reaction times and fewer mistakes on performance tests.66

If you’re going to put your head down on your desk, or against the window of a bus and take that 10-minute nap, the Ostrich Pillow might help you out. It’s sort of like a pillow hood that goes down over your eyes. It allows your forehead or the side of your head to rest on a hard surface, and there are holes at the top for your hands during a desk nap. Another version, the Ostrich Pillow Light, is like a padded sweatband that wraps around your forehead and eyes.

Can’t nap or caffeinate? Try physical movement. Jodie Tingle-Willis, a yoga instructor in Louisville, Ky. recommends a few moves to wake yourself up. “Opening up the chest is really good, so you can take your hands behind you and grab the chair on either side and reach your heart up and forward and take some really nice, deep breaths in and out,” she says. She also recommends a chest-opening side stretch where you leave your left arm by your side, extend your right over your head, and bend to the right.

“A little less conventional is to take off your shoes and actually give yourself a little bit of a foot massage,” says Tingle-Willis. She says pounding gently on the sole of your foot can wake up nerve endings and bring energy into the body.

Michael Bonnet, a professor of neurology at Wright State University School of Medicine, recommends simply getting up and walking around to overcome sleepiness. But, he says the more-sleep deprived you are, the sooner the energizing effect wears off, and the more activity you’ll need.

Your next step: make sleep a priority

Almost every sleep researcher I talked to emphasized the importance of making sleep a priority. Eliza Van Reen, from Brown University emphasizes making a priority of going to bed at a certain time each night and keeping a regular sleep schedule. She says she knows you’ve probably heard that before, and that it’s easier said than done, but it works.

In this article, I didn’t even go into the importance of timing your sleep or understanding circadian rhythms. That stuff matters too, but the fact of the matter is that you probably won’t be successful at harnessing any of those techniques to improve sleep until you decide to make sleep a priority.

And, just like eating less junk food or making a workout pact, committing to sleeping better is not a promise to be made lightly. Getting good sleep is just about the most important step you can do to improving your health, productivity, and well, happiness. While we usually list our specific recommendations at the end of articles, I find it hard to make specific recommendations since sleep is something that everyone knows they need more of, yet we somehow can’t find the will to do it.

So I’ll end with a question.

How will you start sleeping better?

Notes:

  1. American Psychological Association, 2013. Stress in America poll ↩
  2. Huffington Post, 2012. Lack Of Sleep Could Decrease The Potency Of Vaccine: Study ↩
  3. Whiteman, Honor, 2013. Lack of sleep may increase Alzheimer’s risk ↩
  4. Hirschkowitz, Max. (2004) Normal human sleep: an overview. The Medical Clinics of North America, 88(3):551-65. ↩
  5. Wright, Anthony, 2014. Chapter 6: Limbic System: Amygdala, Neuroscience Online. ↩
  6. Carter Lab, University of California, Davis, Cognitive Control. ↩
  7. Walker, Matthew P. (2009) The Role of Sleep in Cognition and Emotion Annals of the New York Academy of Sciences, 1156: 168-197. ↩
  8. Dinges, David F. et. al. (1997) Cumulative Sleepiness, Mood Disturbance, And Psychomotor Vigilance Performance Decrements During A Week Of Sleep Restricted To 4-5 Hours Per Night. Sleep 20: (4) 267-277. ↩
  9. Walker, Matthew P. (2009) The Role of Sleep in Cognition and Emotion Annals of the New York Academy of Sciences, 1156: 168-197. ↩
  10. Taheri, M., Arabameri, E. (2012) The Effect of Sleep Deprivation on Choice Reaction Time and Anaerobic Power of College Student Athletes. Asian Journal of Sports Medicine, 3 (1): 15-20. ↩
  11. Mah, Cheri D. et. (2011) The Effects of Sleep Extension on the Athletic Performance of Collegiate Basketball Players. Sleep, 34 (7) 943-950. ↩
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  15. National Sleep Foundation, 2012. Bedroom Poll. ↩
  16. National Sleep Foundation, 2013. 2013 Exercise and Sleep. ↩
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  20. Mead, M. Nathaniel. (2008) Benefits of Sunlight: A Bright Spot for Human Health.Environmental Health Perspectives, 116(4): A160-A167. ↩
  21. National Sleep Foundation, 2011. Sleep in America Poll. ↩
  22. Gooley, Joshua J. (2011) Exposure to Room Light before Bedtime Suppresses Melatonin Onset and Shortens Melatonin Duration in Humans. Journal of Endocrinology and Metabolism, 96(3): E463-E472. ↩
  23. Wahnschaffe, Amely, et. al. (2013) Out of the Lab and into the Bathroom: Evening Short-Term Exposure to Conventional Light Suppresses Melatonin and Increases Alertness Perception. International Journal of Molecular Sciences, 14(2): 2573-2589. ↩
  24. Harvard Health Letter, 2012. Blue light has a dark side.  ↩
  25. Cajochen, Christian, et. al. (2011) Evening exposure to a light-emitting diodes (LED)-backlit computer screen affects circadian physiology and cognitive performance. Journal of Applied Physiology, 110:1432-1438. ↩
  26. Wood, Brittany, et. al. (2013) Light level and duration of exposure determine the impact of self-luminous tablets on melatonin suppression. Applied Ergonomics, 44(2): 237-240. ↩
  27. Harvard Health Letter, 2012. Blue light has a dark side. ↩
  28. National Sleep Foundation, 2011. Sleep in America Poll. ↩
  29. National Sleep Foundation, 2011. Sleep in America Poll. ↩
  30. Dinges, David F., et. al. (2013) Abstract Supplement. Sleep, Volume 36: 186. ↩
  31. National Sleep Foundation, 2012. Bedroom Poll. ↩
  32. Her, Jin-Gang, et. al. (2014) Development and Comparative Evaluation of New Shapes of Pillows. Journal of Physical Therapy Science, 26 (3): 377-380. ↩
  33. Gordon, S.J.,, et. al. (2009) Pillow use: the behaviour of cervical pain, sleep quality and pillow comfort in side sleepers. Manual Therapy, 14(6):671-8. ↩
  34. Gordon, S.J., Grimmer-Somers, K. (2011) Your Pillow May Not Guarantee a Good Night’s Sleep or Symptom-Free Waking. Physiotherapy Canada,63(2):183-90. ↩
  35. Robinson, Nick, 2014. Sleep Like the Dead. ↩
  36. Onen, L.H., et. al. (1994) [Prevention and treatment of sleep disorders through regulation] of sleeping habits]. La Presse Medicale, 23(10):485-9. ↩
  37. Hirschkowitz, Max. (2004) Normal human sleep: an overview. The Medical Clinics of North America, 88(3):551-65. ↩
  38. American Medical Student Association, 2014. Health Hint: Progressive Muscle Relaxation. ↩
  39. Dayapoglu, Nuray, Mehtap, Tan. (2012) Evaluation of the Effect of Progressive Relaxation Exercises on Fatigue and Sleep Quality in Patients with Multiple Sclerosis. Journal of Alternative and Complementary Medicine, 18(10): 983-987. ↩
  40. Pifarre, P. et. al. (2014) Diazepam and Jacobson’s progressive relaxation show similar attenuating short-term effects on stress-related brain glucose consumption.. European psychiatry, the Journal of the Association of European Psychiatrists, 29 (5). ↩
  41. Beaudoin, Luc P., 2014. My Sleep Button.  ↩
  42. De Koninck, Joseph, et. al. (1983) Sleep Positions in the Young Adult and Their Relationship with the Subjective Quality of Sleep . Sleep, 6(1): 52-59. ↩
  43. Agargun, M.Y. et. al. (2004) Sleeping Position,Dream Emotions,and Subjective Sleep Quality. Sleep and Hypnosis, 6(1): 8-13. ↩
  44. Rasskazova E,, et. al. (2014) High intention to fall asleep causes sleep fragmentation. Journal of Sleep Research, 23(3):295-301. ↩
  45. Vande Griend, J.P., Anderson, S.L.. (2003) Histamine-1 receptor antagonism for treatment of insomnia. Journal of the American Pharmacists Association, 52(6):e210-9. ↩
  46. Medline Plus, 2014. Doxylamine. ↩
  47. Malhrota, Samir, et. al. (2004) The Therapeutic Potential of Melatonin: A Review of the Science. Medscape General Medicine, 6(2): 46. ↩
  48. Howatson, G., et. al. (2012) Effect of tart cherry juice (Prunus cerasus) on melatonin levels and enhanced sleep quality. European Journal of Nutrition, 51(8):909-16. ↩
  49. Fernandez-San-Martin, M.I., et. al. (2010) Effectiveness of Valerian on insomnia: a meta-analysis of randomized placebo-controlled trials. Sleep Medicine, 11(6):505-11. ↩
  50. Silber, B.Y., Schmitt, J.A. (2010) Effects of tryptophan loading on human cognition, mood, and sleep. Neuroscience and behavioral reviews, 34(3):387-407. ↩
  51. Halson, Shona L. (2014) Sleep in Elite Athletes and Nutritional Interventions to Enhance Sleep. Sports Medicine, 44: 13-23. ↩
  52. Chollet, D. et. al. (2001) Magnesium involvement in sleep: genetic and nutritional models. Behavior Genetics, 31(5):413-25. ↩
  53. Abbasi, B. et. al. (2012) The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial. Journal of Research in Medical Sciences, 17(12):1161-9. ↩
  54. National Sleep Foundation, 2012. Bedroom Poll. ↩
  55. Van De Werken, Maan, et. al. (2010) Effects of artificial dawn on sleep inertia, skin temperature, and the awakening cortisol response. Journal of Sleep Research, 19(3): 425-435. ↩
  56. Ikeda H,,Hayashi M. (2010) The effect of self-awakening from nocturnal sleep on sleep inertia.Biological Psychology, 83(1): 15-9. ↩
  57. Van De Werken, Maan, et. al. (2010) Effects of artificial dawn on sleep inertia, skin temperature, and the awakening cortisol response. Journal of Sleep Research, 19(3): 425-435. ↩
  58. Sleep Cycle, 2014. How it works. ↩
  59. asapSCIENCE, 2013Should You Use The SNOOZE Button?  ↩
  60. Vanderkam, Laura. Why your snooze button is evil. CBS Money Watch, June 21, 2012. ↩
  61. Pavia, Ciara. 21 Alarm Clocks You’d Definitely Want To Wake Up To. Buzzfeed, June 28, 2013. ↩
  62. Horne, James, et. al. (2008) Sleep extension versus nap or coffee, within the context of ‘sleep debt’.. Journal of Sleep Research, 17(4): 432-436. ↩
  63. Brooks, A., Lack, L. (2006) A brief afternoon nap following nocturnal sleep restriction: which nap duration is most recuperative?. Sleep, 29(6):831-40. ↩
  64. Tietzel, A.C., Lack, L.C. (2001) The short-term benefits of brief and long naps following nocturnal sleep restriction. Sleep, 24(3):293-300. ↩
  65. Kohler, Mark, et. al. (2008) The effects of chewing versus caffeine on alertness, cognitive performance and cardiac autonomic activity during sleep deprivation.Journal of Sleep Research, 15(4): 358-368. ↩
  66. Anderson, C. Horne, J.A. (2008) Placebo response to caffeine improves reaction time performance in sleepy people. Human Psychopharmacology, 23(4):333-6.