Expert Explains What Occurs in Your Body During Fasting

In recent years, fasting has gained popularity as a weight loss method

An expert has detailed what happens to your body when you fast.

Fasting involves going for an extended period without eating or consuming a significantly reduced amount of calories.

A well-known fasting method is the 5:2 Diet, where a person eats normally for five days a week and consumes only 500-600 calories on the other two non-consecutive days.

Fasting offers several health benefits, including weight loss. It may also aid in blood sugar regulation, enhance heart health, and improve physical performance, according to Johns Hopkins Medicine.

Nonetheless, opinions differ on whether fasting is truly beneficial for the body, due to a lack of human-based studies on the practice.

So, what actually occurs in your body during the initial stages of fasting? Dr. Alan Goldhamer has provided an explanation.

Many individuals engage in fasting for its health advantages

During a conversation with Steven Bartlett on his Diary of a CEO podcast, Goldhamer mentioned that within the first 24 hours, our bodies transition from using glucose as a fuel source to ketones (a type of chemical produced by the liver when it breaks down fats).

"[In the initial 24-48 hours of fasting] the brain, liver, and muscles will predominantly begin to shift - it's a progression based on your glycogen reserves," he explained.

"Within 16 hours/24 hours/48 hours of this transition, you'll move from primarily burning glucose to burning byproducts of fat metabolism."

These byproducts include ketones and beta hydroxybutyric acid (BHB). BHB is a chemical that provides energy when there is an insufficient intake of carbohydrates or sugars.

Besides aiding in weight loss, fasting is also believed to benefit brain health.

Goldhamer told Bartlett: "The higher your [BHB] levels, the more BDNF is produced. BDNF, or brain-derived neurotrophic factor, is a neurochemical considered to protect the brain from oxidative damage."

Oxidative damage can contribute to conditions like Alzheimer's disease and Parkinson's.

Simulations have demonstrated the effects of fasting on the body.

In a detailed analysis, one video reveals that within the first four hours of fasting, your body ceases to digest food.

After eight hours without food, your blood sugar decreases, and your body begins to utilize stored glycogen for energy.

By 12 hours, your body is likely depleted of glucose, prompting the liver to break down fat into ketones.

At 16 hours of fasting, you may experience autophagy, a natural process where the body breaks down and recycles damaged or unnecessary cell components.

As always, consulting a medical professional before making significant dietary changes is advisable.