Overview
Intermittent fasting is one of the most effective methods to lose weight in a timely manner. This diet focuses on a cyclic eating pattern that triggers certain metabolic pathways in the body responsible for weight loss.
Researchers have conflicting opinions about the validity of this diet in the long term and whether or not it’s sustainable. Additionally, there is scarce scientific evidence about the potential side effects of prolonged intermittent fasting, which further complicates the conversation.
In this article, we will discuss the primary mechanisms that mediate the weight-reducing properties of intermittent fasting.
How does intermittent fasting cause weight loss
Hormonal regulation
During fasting, the body makes numerous changes to provide energy for the hungry cells. These changes include modifying the action of the nervous system and adjusting the concentration of hormones.
The first hormone that gets influenced by these modifications is insulin.
Generally speaking, the levels of insulin in the bloodstream varies depending on dietary intake. Shortly after your meal, insulin levels sharply increase to regulate your glucose concentration. Conversely, fasting downregulates the release of insulin from the beta-cells of the pancreas.
Norepinephrine (i.e., noradrenaline) is the second hormone that fluctuates during fasting. This hormone triggers enzymes to break down adipose tissue (i.e., fat deposition) and release fatty acids into the circulation.
The third hormone affected by this process is the Human Growth Hormone (HGH), which increases dramatically during fasting.
Caloric deficit
Despite the seemingly non-restrictive nature of intermittent fasting, it inadvertently leads to weight loss by reducing the number of calories you consume per day.
You see, sticking to a short window during the day where you’re allowed to eat will make you consume fewer calories since you’re less likely to feel hungry in that timeframe.
For instance, if you’re following the 16:8 fasting type, you will condense your daily meals in 8 hours. As a result, your digestive tract will be mostly full, which prevents feelings of hunger and puts you in a state of caloric deficit.
In a 2014 review, researchers found that intermittent fasting reduces body weight by 3–7% when adopted for 3–24 weeks.
They also found that intermittent fasting offers other beneficial health effects.
Faster basal metabolic rate
In addition to hormonal regulation and caloric deficit, intermittent fasting helps you lose weight by accelerating the basal metabolic rate (BMR).
In fact, researchers found that the basal metabolic rate (BMR) of people following the intermittent fasting diet is significantly high.
BMR is responsible for controlling the number of calories your body uses during rest. This number is subject to dozens of factors, including age, gender, weight, height, body type, diet, degree of physical activity, and genetics.
The vast majority of diets slow down BMR, gradually leading to a slower rate of weight loss. However, intermittent fasting seems to produce the exact opposite effect.
Takeaway message
Intermittent fasting is extremely effective in inducing weight loss and promoting a healthier body composition.
