Doctor reveals exact time people need to fast for to lose maximum weight

A diet and weight loss guru has explained the best time people should be fasting - in order to get the maximum weight loss. Dr Mindy Pelz, speaking on her YouTube channel, said that people were asking her how to maximise the “top end weight loss”.

The expert, who has appeared on the Diary of a CEO podcast, said that people want to get the process of ketosis going through fasting. This is is a metabolic state that occurs when the body burns fat for energy instead of glucose.

Keto diets have many possible benefits including potential weight loss, increased energy and treating chronic illness. Dr Pelz said that there was also the issue of autophagy - where a cell breaks down and destroys old, damaged, or abnormal proteins and other substances, which are then recycled for important cell functions, especially during periods of stress or starvation.

She said that in order to get ketosis started, people probably need to fast for 13-15 hours. She said: “So those of you that want to lose weight that 13 to 15 hours is your first ledge to stimulate ketosis so that you burn fat in that moment.

"But here, think about this for a moment. That doesn’t mean that you are going to kick yourself out of insulin resistance. So the name of the game, when we’re looking at using fasting as a really cool tool for weight loss, is how do we not only burn fat but how do we stop you from becoming insulin resistant?"

Intermittent fasting has been shown to have major benefits for insulin resistance and to lead to a reduction in blood sugar levels. Insulin resistance is when cells in the muscles, fat, and liver don’t respond well to insulin and can’t easily take up glucose from the blood. As a result, the pancreas makes more insulin to help glucose enter your cells.

Dr Pelz said to avoid insulin resistance: “We’ve got to get you into this place of autophagy. So the second thing that we’ve got to think about is the longer you fast, the deeper the autophagy and the deeper the autophagy, the more your body gets rid of insulin-resistant cells.

"So that’s 17 hours or longer. Now, you’re in massive cellular repair. 13 to 15 hours, you’re just burning fat from getting energy by burning fat, but you’re not in cellular repair as deep. So make sure if you want to lose weight, you’re going in longer than 17 hours.”

On the issue of when people should eat, Dr Pelz said it should only be during the daylight. She said: “So in the summer, this is a little bit easier because you can have dinner a little bit earlier. But as long as you’re eating in the dark, you are promoting insulin resistance. So that dinner you have at nine o’clock at night when it’s dark out or eight o’clock at night. When it’s dark out, your cells are going to be more insulin resistant to that because Melatonin has come in. “