Most people think of intermittent fasting – restricting your eating to a time frame – as a weight loss strategy. Which it is.

But a new study, set in the real world, has found that even a modest restriction improves mood, sleep, hunger and energy.

These improvements were achieved by participants keeping their eating to a 10-hour window – which in effect meant they were fasting for 14 hours a day.

Some intermittent fasting plans restrict eating to six hours a day – which can be hard work. Whereas a 10-hour a day window is much easier to achieve.

By eating first at 9am, for example, you’d have your last bite at 7pm. You might grumble about missing out on your late night Vegemite toast, but something’s got to give, eh?

The new study

The study comes from the ZOE Health Study a research project that uses data reported via a mobile app. It comes out of King’s College in London.

In this instance, 37,545 users of the ZOE health app were asked to follow their regular eating pattern for one week.

They then switched to a 10-hour eating window for at least two weeks.

The significant findings

One of the most encouraging findings was that more than 96 per cent of the participants opted in for additional weeks of the 10-hour eating plan.

That is, they wanted to keep going with this form of IF plan – suggesting they found it relatively easy and beneficial.

More than 70 per cent of the participants were classified as “highly engaged” – because of their regularity in logging in and completing questionnaires.

Slightly more than half of these highly engaged users reported a small reduction in weight over two to 16 weeks. On average this was about a kilogram.

The main benefits were observed to be increased feelings of wellbeing.

Participants reported sleeping better, feeling less hungry between meals, more energy and enjoying a more stable mood.

What the researchers say

Dr Sarah Berry, a physician, author of the study, and chief scientist with the ZOE Health Study, said:

“Our participants fasted for 14 hours against the noisy backdrop of our day-to-day lives and found there was a big improvement in how they felt.”

She said that a 10-hour eating window is “pragmatic and achievable for most people”.

Dr Berry said she was “surprised that even reducing your eating window by, on average, two hours” delivered these well-being improvements.

She said the study also showed that consistency counts. Those who maintained the same time frame for fasting had greater benefits than those who varied their eating window day to day.

Dr Kate Bermingham, from King’s and ZOE, said:

“This study adds to the growing body of evidence showing the importance of how you eat.”

She said the findings show that “we don’t need to be eating all the time”.

Many people, she said, will feel satiated and even lose weight if they restrict their food to a 10-hour window.

The researchers presented their findings last week at the 2023 European Nutrition Conference in Belgrade, Serbia.