Sleep Deprivation and It's Impact on Body Composition

When most of us look to change our lifestyle to lose weight we often turn towards a healthy diet and exercise. Up at 4am for our first workout, lots of fruits and veggies, and maybe an evening weightlifting session. By the end of the week we are exhausted, hungry and wishing for an extra hour of sleep. Is it worth it to press the snooze button and get that extra hour of sleep? Will that really help you reach your goals? You better believe it…. 

About a third of US adults don’t get enough sleep on a regular basis. Most people think they can get by on less than 7 hours. Some wear it as a badge of honor while throwing out an occasional snide “I’ll sleep when I’m dead” comment as to make their lack of sleep justifiable because they are being productive. How about those that are looking for health and to alter their body composition? They should definitely be making sleep a priority! Numerous research studies show the impact on just a few nights of poor sleep and it’s probably more impactful than you think. 

Let’s start with probably one of the most obvious reasons sleep can effect body composition. People who don’t get enough sleep crave higher calorie foods and have a harder time saying no to impulses. Makes total sense since your body is looking for something savory and full of quick energy to keep you awake. I can’t remember the last time I was tired and thought “Man, I could go for some brussel sprouts and a sweet potato!” Setting yourself up to get MORE sleep especially during times of high stress, increases your chances of making better decisions. 

We also see an increase in the likelihood of developing type 2 diabetes with sleep loss or sleep disturbances. In one study, there was 3.9 times more risk of developing diabetes if patients slept less than 6 hours a night. Glucose regulation is either impacted directly, or by a dysregulation in appetite, which causes poor food choices and weight gain. Both of these directly impact body composition by not only causing us to make poor food choices but impacting glucose and insulin resistance when we eat that food! 

Poor sleep can also effect your hormones, specifically testosterone. Testosterone is an important component of gaining muscle as well as sex drive in both men and women. Sleeping increases testosterone levels while poor sleep quality or quantity decreases them. Protein synthesis, the pathway that helps muscle recovery and rebuilding, is also hindered with poor sleep. Which means a loss of muscle or that you won’t build as much muscle after all that hard work you put in the gym today! 

We can’t stress enough the importance of sleep when it comes to your health and fitness goals. You can have the perfect set of macros and the best fitness programming in the world, but I guarantee if you aren’t getting adequate sleep, you aren’t reaching your full potential!


Author: Jessica Amaral, Black Iron Nutrition Coach, @jessica_c_amaral