Sleep is critical to overall health, yet most adults get less than the recommended amount of sleep each night.

Susan Hewlings, Director of Scientific Affairs

October 9, 2019

3 Min Read
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While the exact physiological reason we sleep is not completely understood, experts agree we require sleep to be healthy, to recover from exercise and to function optimally both physically and cognitively.1 Inadequate sleep increases obesity and inflammation and impairs immune and antioxidant defenses.2,3 Inadequate sleep is associated with heightened emotional reactivity, reduced attention, memory and executive cognitive function.4 This impaired cognitive function is comparable to impairments caused by excessive alcohol consumption.

It is recommended that adults aim for seven to nine hours of quality sleep per night; however, most only get an average of six hours.5,6 Due to the increased recognition regarding the impact of inadequate sleep and the awareness that most adults do not get enough sleep, sleep habits should be included in any healthy assessment and strategies should be developed to improve healthy sleep habits.  

People do not get enough sleep for many reasons, including busy schedules, life stressors, unhealthy lifestyles and diagnosed sleep disorders. Strategies to enhance sleep include improving sleep habits such as decreasing use of electronics during bedtime, maintaining a regular schedule, avoiding foods that increase wakefulness, etc. In addition, dietary supplements have been identified to aide in improving sleep length and quality,3 such as melatonin,7 valerian,8 magnesium,9 lavender,10 tryptophan11 and more.

Of course, an overall healthy lifestyle of a balanced diet and exercise cannot be substituted with supplements. Healthy lifestyle in turn impacts gut health. Dysbiosis, or an imbalance in the gut microbiome can negatively impact sleep.12

Learn more about the sleep habits and strategies from Susan Hewlings during the “Supporting the Cycle: Solutions to Manage Stress and Improve Sleep” session on Wednesday, Oct. 16 at 1:30 p.m., at SupplySide West in Las Vegas. This session is underwritten by PharmaGABA. You can also listen to her discussion on the topic in our INSIDER podcast here

Susan J. Hewlings, Ph.D., R.D., is the co-founder of Substantiation Sciences (, a professor at Central Michigan University, director of scientific affairs for Nutrasource Diagnostics Inc. ( and chief science director for IgY Nutrition ( Hewlings specializes in substantiation from study design to publication. She has over 15 years of experience in the industry and has published in multiple peer reviewed journals, text books and trade publications.



1. Halson S. “Nutrition, sleep and recovery.” European Journal of Sport Science. 2008;8(2):119-126. DOI: 10.1080/17461390801954794.

2. Altman NG et al. “Sleep duration versus sleep insufficiency as predictors of cardiometabolic health outcomes.” Sleep Med. 2012;13:1261–70.

3. Golem DL et al. “An Integrative Review of Sleep for Nutrition Professional.” Adv Nutr. 2014;5(6):742–759.

4. McCoy JG, Strecker RE. “The cognitive cost of sleep lost.” Neurobiol Learn Mem. 2011;96:564–82.

5. Ferrara M, De Gennaro L. “How much sleep do we need?” Sleep Med Rev. 2001;5:155–79.

6. Hirshkowitz M et al. “National Sleep Foundation’s sleep time duration recommendations: Methodology and results summary. Sleep Health. 2015;1:40–43.

7. Bonnefont-Rousselot D, Collin F. “Melatonin: Action as antioxidant and potential applications in human disease and aging.” Toxicology. 2010;278:55–67.

8. Bent S et al. “Valerian for sleep: a systematic review and meta-analysis.” Am J Med. 2006;119(12):1005–1012.

9. Rondanelli M “The effect of melatonin, magnesium, and zinc on primary insomnia in long-term care facility residents in Italy: A double-blind, placebo-controlled clinical trial.” J Am Geriatr Soc. 2011;59:82–90.

10. Lillehei AS, Halcon LL. “A Systematic Review of the Effect of Inhaled Essential Oils on Sleep.” The Journal of Alternative and Complementary Medicine. 2014;20(6):441-451.

11. Markus CR “Evening intake of lactalbumin increases plasma tryptophan availability and improves morning alertness and brain measures of attention.” Am J Clin Nutr. 2005;81:1026–1033.

12. Parekh PJ, Oldfield ECI, Johnson DA. “The Effects of Sleep on the Commensal Microbiota: Eyes Wide Open?” Journal of Clinical Gastroenterology. 2018;52(3):204-209.

About the Author(s)

Susan Hewlings

Director of Scientific Affairs, Nutrasource

Susan Hewlings, PhD, RD, is director of scientific affairs at Nutrasource.

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