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Sleep and Fat Loss

One component to body composition change – losing fat mass – is strongly linked to sleep.

Losing fat requires the body to be in a caloric deficit, which means using more energy than your body takes in.  This can be accomplished by restricting calories through diet and/or increasing calories used though exercise, and most people usually typically use some combination of the two. This is sometimes referred to as “calories in/calories out.”


Which brings us back to sleep. Losing sleep can sabotage your fat loss goals by hijacking both the “calories in” AND “calories out” sides of the equation.  Here’s how: Lack of healthy sleep throws off your body’s hormonal profile. This includes the hormones that regulate your appetite: ghrelin, which is associated with feelings of hunger, and leptin, which is associated with feelings of fullness. Ghrelin concentrations are known to spike right before meals, prompting you to eat.


Lack of sleep can severely interfere with your body’s ghrelin/leptin balance, resulting in an increase in ghrelin and a reduction in leptin levels.  Essentially, the less you sleep, the more you mess with the hormones that regulate your hunger levels.

It’s already hard enough to restrict your caloric intake when you’re trying to lose fat mass. Imagine how much more difficult it will be if you’re sleep deprived and make your body tell your brain that it’s hungrier than normal.

Then you’re supposed to resist your body’s hormonal demands when you’re a) already tired from lack of sleep b) tired from being in a caloric deficit or c) probably hungry from making changes in your diet?


Sleep, and the lack of sleep, also has a significant effect on the second group of hormones, the catabolic hormones, and specifically a hormone called cortisol. 

Cortisol is a hormone that is released in response to stress.  It’s designed to break down tissue – including muscle tissue – for the purpose of giving the body energy it needs to deal with whatever stressful situation your body has to deal with. As it turns out, sleep can have an effect on cortisol secretion as well, but if your goal is to increase your muscle mass, it’s not a positive one.

Research has shown that during both restricted sleep and complete sleep deprivation, cortisol levels were elevated the following evening by 37-45%potentially “accelerating the development of metabolic and cognitive consequences of glucocorticoid excess.”

In plain speech, because cortisol has a catabolic (muscle-reducing) effect, increased cortisol levels due to lack of sleep can threaten your muscle development. Once you add in the reduced GH and testosterone levels produced by lack of sleep, the overall effect of not sleeping enough can seriously hamper your efforts to gain muscle and increase your Lean Body Mass.




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Sleep Matters

at Blue Phoenix Wellness

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I am now taking bookings for virtual treatment sessions using various modalities including hypnosis, Emotional Freedom Technique, Neuro-Linguistic Programming and other methods for creating rapid change. This enables me to provide you with support and treatment for your insomnia (and many other issues) in the comfort of your own home. This has two terrific advantages:

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