Why is Sleep Important For Weight Loss?

Adequate Sleep and Weight Loss

Sleep; one of the last mysterious medical frontiers scientists strive to understand. There’s a lot we do understand about sleeping — how it helps our brain clear away toxins and waste accumulated throughout the day, how it restores and maintains cognitive function, and how it allows for vital cellular repairs throughout the body — and then there are still other things that evade our full understanding; questions like, “why we dream” and “how come we evolved to sleep when it was entirely disadvantageous for our ancestors?”
In our pursuit of understanding the mind, scientists have put forth many answers to the vital roles sleep has for us. They’ve tied memory processing, emotion stability, and biochemical processes to sleep. Yet, scientists haven’t fully uncovered how we as a species developed to sleep.
While there still remains so much to understand behind the science and evolution of sleeping, science can at least elucidate important aspects that it has on our health. One of the most important things we understand sleep to do is how it helps our bodies function how they’re meant to. And that includes the role sleep has on metabolic regulation and weight loss. Indeed, sleep is an often overlooked aspect of people’s weight loss journey. Unfortunately, as a result, people often encounter plateaus to their weight loss despite dieting and exercise.

Sleep More, Weigh Less

A third of Americans report that they don’t get enough sleep a night. When the recommended amount of sleep a night falls between seven and nine hours, that means a third of the US is hardly getting enough sleep for their day-to-day activities. Five to six hours of sleep may be okay here and there, but, habitually, there are inevitable consequences. Ignoring the ramifications of tired people commuting and working dangerous or high-intensive jobs, it certainly has consequences on one’s health.
Upon waking up from a reduced sleep cycled, people report feelings of extreme grogginess and lethargy. These feelings have cascading effects on our behaviors, affects, and drives. This is a direct result of dulling to the frontal lobe brought upon by lack of rest; importantly, the frontal lobe of the brain is responsible for people’s decision-making and impulse control. Consequently, decision making becomes less clear-cut.
Additionally, the brain’s reward centers increase in our sleep-addled state, meaning that we’re inclined to find things that reward and satisfy us. In the context of weight loss, having overactive reward centers in the brain firing compounded by a dulled frontal lobe means that the self-control not to succumb to junk-food cravings becomes nigh impossible. Consistent and healthy dieting goes out of the window when the body subconsciously demands feel-good foods like heavy carb snacks.
Studies conducted by the American Journal of Clinical Nutrition and the University of Chicago showed that sleep-deprived people increased their late-night snacking and opted for foods dense in carbs and fats twice as much then participants who got a full eight hours of rest.
Furthermore, other studies have found that sleep-deprived individuals struggled with portion control, eating twice the size of recommended portions compared to control groups.

Sleep and Metabolism

What happens on a biochemical level when we’re sleep deprived? Little amounts of sleep cause our body to react by triggering a hormone called cortisol, a stress hormone. Cortisol levels spike in tired individuals, resulting from the body believing it needs to conserve more energy. In other words, our body wants to hang onto fat instead of using it for fuel.
A study that supported this claim had been conducted on a group of dieters who had been consistently logging the same dietary caloric restrictions before undergoing the experiment. For two weeks, the group cut back on the recommended eight hours and began to face troubles losing weight. Despite eating the same amount of calories from before, their bodies clung to their fat stores, resulting in their weight loss of fat to nearly drop by half than when well-rested. Furthermore, these participants were drained of energy and reported feeling less full from meals.
The body’s ability to process insulin is also impacted while sleep-deprived by more than 30 percent. Within only a span of four days of inadequate rest, blood results showed that patients’ ability to process insulin was amok. Insulin, a hormone that allows the body to convert sugars and starches into energy, is integral for weight loss; due to a diminished ability to process insulin, patients’ bodies had more difficulty processing fats in their bloodstream, resulting in greater storage of fat.

Ghrelin and Leptin

Regarding hormones stimulated by a lack of sleep, ghrelin and leptin are two more essential hormones for weight. These two hormones are known as our appetite hormones; they directly influence feelings on hunger and being satiated.
Ghrelin, also known as the “hunger hormone,” is released in the stomach that signals feelings of hunger in our brains. Levels of ghrelin are high before eating, when stomachs are empty, and low after they’re full.
Inversely, leptin, secreted from fat cells, is a hormone that suppresses or decreases appetite. As ghrelin levels drop, leptin levels increase. This inverse relation between the hormones helps us to know when to start and stop eating. Unsurprisingly, though, when adequate sleep levels aren’t achieved, more “hunger-inducing” hormones are made while less leptin is created. As a result, the body believes it needs to eat more than usual to feel full.
These findings have been supported in a study of over 1000 participants, where sleep-deprived people had 15% higher levels of ghrelin and 15.5% less leptin than the control group.
As it should be understood, sleep affects a much greater scope of our physiological pathways. Aside from just hunger regulation and self-control, sleep is vastly important for the rest of the human body’s proper maintenance and functioning. It influences all our cells, influences hormones’ availability, and where hormones are delivered to, and much more.
It is nearly impossible to lose weight without getting proper sleep; as shown, we lose our ability to regulate self-control of what we eat and how much we eat. Don’t sabotage yourself on your weight loss journey. Treat yourself right and get the rest you deserve. In the long-term, your body will thank you.
For more information about sleep and its effect on your physiology, contact Vitality Aesthetic & Regenerative Medicine.