There are many ways of losing weight. Intermittent fasting is one of them (1).
Intermittent fasting is a pattern of eating that involves consistent short-term fasts. It also involves periods of no food consumption or very minimal food intake.
Intermittent fasting is known to aid weight loss. When you fast for short periods, you’ll eat fewer calories. This leads to weight loss over time (1).
It is worth mentioning that intermittent fasting can also help modify risk factors for chronic conditions like cardiovascular disease and diabetes. For example, it lowers blood sugar and cholesterol levels (2, 3, 4, 5).
In this article, I will discuss intermittent fasting and how it helps with weight loss.
Its effects on your hormones
Intermittent fasting helps with weight loss, but also, it affects your hormones.
Why is this so? It is because your body stores energy (calories) as fat.
When you fast or don’t eat, your body will undergo several changes to improve access to stored energy.
Such changes include changes in the activity of your nervous system and changes in the level of vital hormones.
Two significant metabolic changes that occur during fasting include (6, 7):
· Insulin: When you eat, your insulin level increases. On the other hand, insulin levels fall drastically when you fast. Lower insulin levels facilitate fat burning.
· Noradrenaline: It is also known as norepinephrine. The nervous system releases noradrenaline to the fat cells, causing the breakdown of body fat into free fatty acids. Your body then burns these fatty acids for energy.
It is worth mentioning that short-term fasting increases fat burning. However, studies have shown that alternating-day fasting and whole-day fasting trials lasting 3–12 weeks and 12–24 weeks, respectively, helps reduce body fat and weight (8, 9).
However, there is still a need for further research to examine the long-term effects of intermittent fasting.
Fasting also alters the level of human growth hormone (HGH). In fact, during fasting, HGH levels may increase as much as 5-fold (6, 7).
Initially, HGH was believed to enhance the burning of fat. However, new research shows that HGH facilitates the conservation of energy by the brain, thus making it difficult to lose weight (10).
HGH increases appetite and impedes energy metabolism by activating a group of neurons in your body known as agouti-related protein (AgRP).
Intermittent fasting promotes weight loss by helping you to eat fewer calories and carbohydrates.
All intermittent fasting protocols involve skipping meals during the fast. So, technically, whenever you’re on an intermittent fast, you’re consuming fewer calories, unless, of course, you compensate by eating more during the feeding periods.
A 2014 study (11) published in the journal Translational Research found that intermittent fasting caused a 3–8% reduction in body weight over a timeline of 3–24 weeks.
Further investigation shows that intermittent fasting may cause weight loss at a rate of 0.55–1.65 pounds (0.25–0.75kg) weekly (12).
The same study also showed that weight loss reduced waist circumference by 4–7%, indicating that the participants lost belly fat.
This implies that intermittent fasting greatly aids weight loss.
That said, intermittent fasting does not only help with weight loss. It has many other health benefits, including reducing the risk of cardiovascular disease (13, 14).
Yes, calorie counting isn’t required during an intermittent fast. But then, it is worth mentioning that weight loss is mediated by a reduction in the intake of calories.
There are a couple of things that you should consider if you want to lose weight via intermittent fasting: