How Does Intermittent Fasting Affect Your Metabolism?

How Does Intermittent Fasting Affect Your Metabolism?

Jun 28, 2023

Intermittent fasting is an eating pattern that cycles between periods of fasting and eating. It does not focus on what you eat, but rather when you eat. Typically this method involves limiting your daily eating window to a specific number of hours. (e.g. an 8-hour window, such as from 12 pm to 8 pm, and fast for the remaining 16 hours of the day).

It is essential to stay hydrated and ensure adequate nutrient intake during the eating periods to support overall health.

I.F. can improve insulin sensitivity.

Insulin is a hormone responsible for regulating blood sugar levels. When you fast, insulin levels decrease, which allows your body to become more sensitive to insulin when you do eat.

Improved insulin sensitivity can enhance the body's ability to utilize glucose effectively, potentially reducing the risk of insulin resistance and type 2 diabetes.

I.F. can promote fat burning.

During fasting periods, the body's glycogen stores become depleted, and insulin levels decrease. As a result, the body switches from using glucose as its primary energy source to burning stored body fat for fuel. This shift can promote fat loss and contribute to improvements in body composition.

More on insulin sensitivity in a bit...

I.F. can stimulate "autophagy".

Autophagy is a cellular process in which damaged or dysfunctional cellular components are broken down and recycled. Intermittent fasting has been shown to stimulate autophagy, which can help improve cellular health and potentially slow down the aging process.

*For the nerds*: The word "autophagy" comes from the Greek words "auto" (self) and "phagy" (eating), indicating that it is a process of self-eating which makes sense as to it involves the breakdown and recycling of damaged, dysfunctional, or unnecessary cellular components.

I.F. can increase HGH production.

Intermittent fasting has been found to increase the production of human growth hormone (HGH). Cellular repair mechanisms (Autophagy) are associated with increased HGH release.

During fasting, the body shifts from using glucose as the primary fuel source to burning stored body fat. This process, known as lipolysis, increases the utilization of fatty acids as energy. Fatty acids play a role in stimulating HGH release.

HGH plays a crucial role in promoting fat burning, muscle growth, and cellular repair. Higher levels of HGH help boost metabolism and support overall metabolic health.

The Relationship between Insulin and HGH:

Insulin and HGH have an inverse relationship, meaning when insulin levels are high, HGH production tends to be suppressed.

By reducing insulin levels and improving insulin sensitivity, intermittent fasting allows for higher HGH production.

HGH also influences glucose metabolism. It can stimulate the liver to produce glucose (gluconeogenesis) and reduce the uptake of glucose into cells. These actions can help maintain blood sugar levels during fasting periods but may also reduce insulin sensitivity if HGH levels remain chronically elevated.

I.F. can help preserve muscle mass.

Some studies suggest that intermittent fasting may have a minimal effect on resting metabolic rate (RMR), which is the number of calories your body burns at rest each day . While early research suggests that short-term fasting may slightly decrease RMR, it is important to note that any potential decrease in metabolic rate is generally compensated by other metabolic adaptations.

Additionally, intermittent fasting can help preserve muscle mass, which contributes to a higher RMR. This one can truly go either way, but I wanted to include it as one "effect" that really doesn't have a clear answer yet!

So should you start intermittent fasting?

My honest and personal opinion is that there are so many means to the same end. People who struggle losing weight before I.F. could possibly just see results with I.F. because it stopped them from their habit of eating 500 calories over their caloric intake every night in snacks. There is clear science behind time-restricted eating, but fact of the matter is, there are many avenues that will work as long as one remains consistent.

If it works for your lifestyle and you see noticeable changes in energy and control over food, why not give it a shot! But rather than do it for the trend, hopefully now you've learned some science behind it.