How Sleep and Weight Gain Are Related


It is important to get plenty of sleep each night. There are numerous reasons for needing sleep. Today we are focusing on how not getting enough sleep could lead to weight gain. I chose to cover this specific reason because many people join the gym to try to lose weight. No matter how hard you work in the gym, if you are not living a healthy lifestyle outside of the gym, you most likely will not see many (if any) improvements. One important part of living a healthy lifestyle is to make sure you are getting enough sleep each night.

Especially in the direction that the world is going today with two-wage earner households and 24-hour entertainment through television and the internet, it has become increasingly difficult to get enough good quality sleep.  In 1998, only 35% of Americans were getting eight hours of sleep. This number has since dropped to 26% in 2005.1 This lack of sleep is causing a bad cycle of overeating and not sleeping well that is not helping anyone improve their health.  Enough sleep each night is needed so that your body can go through the sleep cycle and obtain the benefits from the each stage. What happens in each stage is listed below.

  • N1: between being awake and being asleep
  • N2: Onset of sleep
  • N3: deepest and most restorative sleep
  • REM: Occurs about 90 minutes into sleep and repeats about every 90 minutes throughout the night

*** To learn about what happens to your body during each stage please visit the following website:

If sleep is cut short (ie. You are not getting the full eight hours needed), “the body doesn’t have time to complete all of the phases needed for muscle repair, memory consolidation and release of hormones regulating growth and appetite.”2

Sleep has a large effect on your hormones. Two hormones that mainly effect your appetite are leptin and ghrelin. Leptin tells you when you are full, and ghrelin tells you when you are hungry. When you are not getting enough sleep, leptin levels decrease and ghrelin levels increase. This leads to you over eating, especially carbohydrates.4 Those who do not get enough sleep are typically seen eating smaller breakfasts but then increasing food intake throughout the day. Those who are not getting enough sleep are also seen getting 42% more calories from carbohydrates, protein, and fiber at night after dinner compared those who obtained enough sleep.4   

The findings provided by research, “indicate that total sleep deprivation or insufficient sleep both increase daily food intake, thus providing further support that one function of sleep in humans is to conserve a small but physiologically meaningful amount of energy.”4 Insufficient sleep is now considered an independent risk factor for weight gain and obesity. Obesity is then a risk factor for cardiovascular disease. It is important to get enough sleep so that you are not trying to find the energy you missed in food!


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