Diet, exercise, and sleep: How the three pillars of health work together

Fad diets and fitness crazes get a lot of media attention. Celebrity spokespeople promote weight loss programs, exercise equipment, and “miracle” supplements. The promise of better health and wellbeing is promised if you just eat right and exercise daily.

Diet and exercise are certainly important, but if you’re only focused on these two “pillars of health” you’re missing an essential component: sleep.

Sleep is the important third pillar of health that is too often overlooked. In fact, not only is sleep important to your overall health, a good night’s sleep can actually improve your fitness and diet effort1

Sleep loss makes working out less appealing

Multiple studies have shown that partial and chronic sleep deprivation actually has little effect on functions such as muscle strength, lung capacity, or speed times.1 However, lack of sleep does increase risk of depression and fatigue. 1 So whilst physical performance may not be heavily impacted by poor sleep, your desire to work out may decrease as your mood worsens. Sleep deprivation also impairs accuracy and decision-making1, meaning your touch footy skills could suffer if you routinely skip sleep!

Those with obstructive sleep apnea (OSA) may find it even harder to work out. Not only are sufferers not getting enough quality sleep, but OSA often goes hand in hand with being overweight.2 Weight gain affects respiratory function, making it harder to sustain activity for longer periods of time.3 It’s a vicious circle—you’re too tired to exercise due to sleep apnea, which leads to weight gain that can worsen OSA.

Sleep deprivation makes dieting harder

We now know that restful sleep can positively impact your workout routine, but what about your diet? Surely sleep is less important than cutting calories? Not entirely—poor sleep could be sneakily sabotaging your efforts to eat well.

The sleep-deprived often find it harder to lose weight for a number of reasons. For starters, dieters who sleep too few hours feel hungrier and tend to overeat.4,5 Sleep helps keep two hunger-regulating hormones—ghrelin and leptin—stable, and lack of sleep makes it harder for your body to control these hormones.6 Interestingly, a 2008 study suggests that just one night of sleep deprivation can cause an increase and decrease in ghrelin and leptin levels, respectively,   thus increasing your appetite the next day. 7

Not getting enough sleep can also affect your food choices. One study found that participants who slept fewer hours not only snacked more, but craved carbohydrate heavy nibbles.8 There is also evidence that sleep deprivation reduces people’s self-control9 making you even more likely to choose junk food over healthier snacks.Even if you manage to avoid overeating or indulging in a few extra Tim Tams, sleep loss changes the body in ways that makes losing weight more difficult. If you’re sleep deprived you may still shed some kilos, but the mass lost is more likely to be from muscle or stored carbohydrates than from body fat.10 One study even found that after a week of restricted sleep (just 4 hours per night), previously healthy participants had the same glucose and insulin levels of diabetics.11

Tips for better sleep

Now that you understand the link between the three pillars of health, how can you improve the sleep portion of this trio beyond the usual advice?

  • Stay active (or start working out, if you don’t already). People who exercise regularly generally report better sleep quality and fewer disruptions to their sleep.12,13 You don’t have to go straight from the sofa to running a 5km-- any exercise is better than none.
  • Workout at the right time. When is the right time to exercise? Whatever time works best for you! Exercising at night is considered a no-no, but its negative impact on sleep may be overstated. 14 So go ahead and take a walk, lift weights, or play backyard cricket whenever the mood strikes.
  • Don’t go to bed on a full stomach. It takes a few hours for food to digest, and lying down during this process can trigger acid reflux and heartburn,15 possibly leading to disturbed sleep.16 Try to finish dinner at least three hours before bed, and avoid any known triggers if you do suffer from acid reflux.
  • But don’t go to bed hungry, either! Going to bed feeling starved won’t help you fall asleep. A light snack is all you need to keep a rumbly tummy at bay. Try a food high in potassium, like bananas, 17 or a small bowl of cereal and milk18. Not only are these foods healthy, but they also promote sleep16,17

The sleepvantage Team


  • Reilly T, Edwards B. “Altered sleep-wake cycles and physical performance in athletes.” Physiology & Behavior. 2007; 90: 274-284. 
  • “Sleep Apnea” The Mayo Clinic. 25 Aug 2015. 4 Dec 2015.
  • Salome CM, King GG, Berend N. “Physiology of obesity and effects on lung function.” Journal of Applied Physiology. 29 October 2009; 108: 206-211.
  • Brondel L, Romer MA, Nougues PM, Touyarou P, Davenne D. “Acute partial sleep deprivation increases food intake in healthy men.” The American Journal of Clinical Nutrition., June 2010; 91(6): 1550-1559.
  • Weiss A, Xu F, Storfer-Isser A, Thomas A, Ievers-Landis CE, Redline S. “The association of sleep duration with adolescents' fat and carbohydrate consumption.” SLEEP. 2010;33(9):1201-1209.
  • Taheri S, Lin L, Austin D, Young T, Mignot E. “Short Sleep Duration Is Associated with Reduced Leptin, Elevated Ghrelin, and Increased Body Mass Index.” PLOS Medicine. December 2004; 1(3): 210-217.
  • Schmid SM, Hallschmid M, Jauch-Chara K, Born J, Schultes B. “A single night of sleep deprivation increases ghrelin levels and feelings of hunger in normal-weight healthy men.” Journal of Sleep Research. 2008; 17: 331-334.
  • Nedeltcheva AV, Kilkus JM, Imperial J, Kasza K, Schoeller DA, Penev PD. “Sleep curtailment is accompanied by increased intake of calories from snacks.” The American Journal of Clinical Nutrition. Jan 2009; 89(1): 126-133.
  • Pilcher JJ, Morris DM, Donnelly J, Feigl HB. “Interactions between sleep habits and self-control.” Frontiers in Human Neuroscience. 11 May 2015; 9: 284.
  • Nedeltcheva AV, Kilkus JM, Imperial J, Schoeller DA, Penev PD. “Insufficient sleep undermines dietary efforts to reduce adiposity.” Ann Intern Med. 5 Oct 2010; 153(7): 435-441.
  • Knutson KL, Spiegel K, Penev P, Van Cauter E. “The Metabolic Consequences of Sleep Deprivation.” Sleep Med Rev. June 2007; 11(3): 163-178.
  • Reid KJ, Baron KG, Lu B, Naylor E, Wolfe L, Zee PC. “Aerobic exercise improves self-reported sleep quality of life in older adults with insomnia.” Sleep Medicine. October 2010; 11(9): 934-940.
  • Singh NA, Clements KM, Fiatarone MA. “A Randomized Controlled Trial of the Effect of Exercise on Sleep.” Sleep. 1997; 20(2): 95-101.
  • Myllymaki T, Kyrolainen H, Savolainen K, Hokka L, Jakonen R, Juuti T, Martinmaki K, Kaartinen J, Kinnenun M, Rusko H. “Effects of vigorous late-night exercise on sleep quality and cardiac autonomic activity.” Journal of Sleep Research. 2011; 20: 146-153.
  • "GERD.” The Mayo Clinic. 31 July 2014. 23 October 2015.
  • Jung H-K, Choung RS, Talley NJ. “Gastroesophageal Reflux Disease and Sleep Disorders: Evidence for a Causal Link and Therapeutic Implications.” Journal of Neurogastroenterology and Motility. 2010; 16(1): 22-29.
  • Drennan MD, Kripke DF, Klemfuss HA, Moore JD. “Potassium Affects Actigraph-Identified Sleep.” Sleep. 1991; 14(4): 357-360.
  • Food and Sleep.” The National Sleep Foundation. December 2009.  23 October 2015