Is intermittent fasting the diet for you? Here's what the science says - Global Circulate

These are the basics for successfully following an intermittent fasting diet?

Simply stated, intermittent fasting is defined by alternating set periods of fasting with periods in which eating is permitted.

Consuming carbohydrates and fats leads to a rise in blood glucose and also lipid levels, which include cholesterol and triglycerides.

The insulin helps tissues throughout the body take up the glucose and lipids, which supplies the tissues with energy.

About three to 18 hours after a meal – again, depending upon a person’s activity level and size the of the meal – the amount of circulating blood glucose and lipids returns to baseline levels.

So tissues then must rely on fuel sources already in the body, which are the glycogen and fat.

A hormone called glucagon, secreted by the pancreas, helps facilitate the breakdown of glycogen and fat to provide energy for the body between meals.

This helps maintain the right level of blood glucose levels.

When the body reaches a true fasting state – about 18 hours to two days without additional food intake – the body’s stores of glycogen are depleted, and tissues like the heart and skeletal muscle start to rely heavily on fats for energy.

Though many tissues adapt to using fats for energy, the brain and red blood cells need a continual supply of glucose.

But when glucose is not available because of fasting, the body starts to break down its own proteins and converts them to glucose instead.

The body continues to synthesize glucose for those cells and tissue that absolutely need it, but the breakdown of stored fats increases as well to provide energy for tissues such as the skeletal muscle, heart, liver and kidneys.

Blood glucose and lipids return to basal levels, and energy levels in the body are seamlessly maintained by transitioning between the metabolic pathways described earlier.

The body is well-equipped to adapt between periods of feasting and fasting.

Indeed, intermittent fasting diets have produced clinically significant amounts of weight loss.

Intermittent fasting may also reduce disease risk by lowering blood pressure and blood lipid levels.

On the flip side, numerous studies have shown that the weight reduction from intermittent fasting diets is no greater than the weight loss on a standard calorie-restricted diet.

In fact, the weight loss caused by intermittent fasting is due not to spending time in some sort of magic metabolic window, but rather to reduced overall calorie consumption.

This is important, because nearly a quarter of the weight lost on any diet is muscle tissue, and the efficacy of intermittent fasting for weight loss has been demonstrated for only short durations.