Intermittent fasting for weight loss: What the science says

26 - 8 - 2022

Here's what evidence says about the efficacy – and safety – of different styles of intermittent fasting for weight loss.

Intermittent fasting for weight loss can be an effective way to lose unwanted fat, particularly in those with obesity and metabolic syndrome. Multiple studies have found that the metabolic impact of intermittent fasting, coupled with the calorie deficit that it tends to generate, can help to create a downward trend on the scales. There are different styles of intermittent fasting, so if you're looking to embark on this approach it's important find the right eating pattern for you. Whether it’s a more extreme form like the 5:2 diet, or a gentler approach such as 16: 8 intermittent fasting, intermittent fasting should be sustainable and fit with your lifestyle.

In this article, we'll break down the science behind intermittent fasting for weight loss, and which approaches are most effective. Plus, we've spoken to experts in cardiometabolic health and oncology about the best ways to lose weight sustainably and safely through intermittent fasting. Remember, it's best to consult a qualified medical professional or registered dietitian if you are considering making significant changes to your diet. 

Intermittent fasting can be effective in reducing body weight in people of every size, according to a report in Nutrition Reviews(opens in new tab). Most studies focused on alternate day fasting or whole-day fasting trials, but there is also evidence to support the success of time-restricted eating. As well as weight loss, intermittent fasting can have cardiometabolic benefits for those with obesity, as found in another review in the 2021 Annual Review of Nutrition(opens in new tab).


Similar to the way the keto diet helps with weight loss, intermittent fasting can put you into a state called ketosis where you are using ketones as fuel. A study in the journal of Cell Metabolism indicates that in the state of ketosis, the body metabolizes fat and produces ketones, which the body can use as an alternative energy source.

Reference:  Live Science