The definition of sleep varies in different studies, but they mostly show, that less than 8 or 9 hours per day is classed as having an insufficient or lack of sleep (although it is perfect for some).
There are several ways in which poor sleep can influence your weight gain. These can vary from specific changes in your metabolism to overall fatigue, all of which can impact your way of life and dietary choices throughout the day.
Studies have highlighted the following vital mechanisms behind deprived sleep and weight gain:
Increase in Fatigue:
This leads to reduced overall physical activity and reduced calorie expenditure.
Brain Alterations:
It might also have many neurological consequences on the brain which trigger an increased calorie consumption need.
Increased Ghrelin Levels:
Ghrelin we known as the hunger hormone. This can cause a surge in appetite and make you eat more, thus making it harder to stick to your diet. One study found that ghrelin levels increased by up to 28% without proper sleep.
Decreased Leptin Levels:
Leptin is the opposite hormone of ghrelin. Leptin sends signals to the brain telling you that you’re full and when to stop eating. And as these levels decrease, you still find that you continue eating, even if you have no sense of hunger. One study showed leptin levels fell by up to 18% without proper sleep.
Increase in Processed Food Intake:
Research has shown the desire to eat more calorie-dense, high-carbohydrate (and fat-intense) meals, increases.
One research study showed a massive 33% increase in an individual’s wish to eat more energy-dense foods after having a miserable night’s sleep.
Increase in Hunger & Appetite:
Associated with the changes in the hunger hormones, research shows us that poor sleep will increase both hunger and appetite in equal measure.
Diminished Exercise Performance: As well as the reduction in the desire to exercise,sleep is also shown to reduce performance while in the gym. This might hamper further muscle growth, physical output, or quantity of work and volume during a training session. All of these aspects are crucial for physique enhancement.
Decreased Carbohydrate Metabolism:
Having poor/insufficient sleep might also adjust how your body handles glucose (the blood sugar leveling). This can mean that you store more fat from precisely the same meals.
A Decrease in Insulin Sensitivity:
This is closely linked to the above. Insulin sensitivity is closely related to muscle growth, overall health, contracting disease, and fat loss (in general). To sum it up, research implies that the more insulin-sensitive your body becomes, the more fat you can lose and muscle you can grow.
An Increased Opportunity for Eating:
This might sound simple, but if you sleep less you spend more time awake, which increases your opportunities for extra eating. This will instantly increase calorie and food consumption, and we know this is a key factor in gaining weight.
Lack of Sleep & Immune Function:
Even when you have one night of distorted or reduced sleep, this can reduce the body’s immune functions. This can lead you to become sick more frequently and also make it more difficult to recover from your training. This is especially true while dieting.
Reduced Testosterone Levels:
Testosterone levels in modern man have swiftly waned. Low testosterone levels are now a common health issue. This is linked primarily to unhealthy lifestyle choices like having poor sleep. Low testosterone levels have been shown to lead to increased fat gain while causing muscle loss.