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Want to lose weight? Time your meals

The timing of meals may be key to weight loss – not cutting out all carbs from your diet, researchers claim.

Evidence already shows slashing calories and exercising more can help overweight adults battle their bulging waistlines.

But an array of new trials is delving into the benefits of time-restricted feeding (TRF), which allows people to eat what they want within a time frame.

The process, deemed similar to fasting, has been proven to have a host of benefits for mice, including weight loss and a lower risk of diabetes.

Scientists paving the way now believe it could help humans – despite no such confirmation TRF works. 

An array of new trials is delving into the benefits of time-restricted feeding (TRF), which allows people to eat what they want within a time frame

Dr Satchin Panda, a biologist at the Salk Institute in San Diego, began studying the effects of TRF almost 15 years ago.

He has now adopted the fasting method in his own life, eating breakfast at 7am and dinner at 7pm – with no food between those times.

Dr Panda told The Washington Post that since he began TRF his blood sugar levels have dropped, he has lost weight and sleeps better.

The positive effects have even led to his mother and 15-year-old daughter both deciding to try the regime.

He claims eating all the time ‘messes up’ the circadian rhythm – which dictate the best time for humans to eat, drink and even have sex.

He and colleagues discovered in 2008 that TRF was beneficial to mice. It saw two sets of mice eat the same amount of calories. However, one group did so within an eight-hour window.


Dr Courtney Peterson and researchers at the University of Alabama at Birmingham followed 11 men and women with excess weight for eight days, in results published last January.

The study marked the first human test of early time-restricted feeding.

For four days, volunteers would eat only between 8am and 2pm, with their last meal by the mid-afternoon and nothing again until breakfast the next morning.

They also tried four days of eating between 8am and 8pm – what many consider to be ‘normal’.

Researchers then tested the impact of eTRF on calories burned, fat burned and appetite.

Participants completed both eating schedules, ate the same number of calories both times and completed all testing under supervision.

Researchers found that, although eTRF did not affect how many total calories participants burned, it reduced daily hunger swings and increased fat burning during several hours at night.

Whether eTRF helps with long-term weight loss or improves other aspects of health is still unknown.

Dr Peterson says that, because the human study involved only a small number of participants, a more comprehensive study will need to take place.

Dr Panda and his team found that the TRF mice weighed 28 per cent less within just four months. He branded the results as ‘so unexpected’.

The experiment was repeated three times, where it was shown to stop mice from developing diabetes, heart disease and cancer.

Dr Courtney Peterson, a nutrition scientist based at the University of Alabama at Birmingham, is another fan of TRF.

She has adopted a fasting regime that allows her to eat between 8am and 2pm for five days a week.

‘I think that within 10 years we will have some really clear guidelines for meal timing,’ she told WP. ‘But we are in the early stages of this research.’

Dr Peterson discovered the benefits of TRF in humans last January after studying 11 overweight patients. The results are yet to be published in a journal. 

She and colleagues found people who ate between 8am and 2pm were not hit by hunger pains late at night, and kept their appetite levels even.

Those who followed the schedule of most adults – eating between 8am and 8pm – suffered cravings all the way up to when they went to bed. 

Dr Peterson told Daily Mail Online at the time that eating earlier in the day, in line with the body’s circadian clock, may influence health.

Many aspects of the metabolism are at their optimal functioning in the morning, including maintaining blood sugar levels and fat burning.

The study revealed that the participants on a TRF diet had reduced levels of ghrelin – a hormone that triggers hunger – and burned more fat.

But Dr Peterson believes the effects of fasting regime will be different between humans and mice, which are nocturnal and live for three years.

She told WP’s David Kohn: ‘It may be that for a mouse, a 16-hour fast is the equivalent of a two or three day fast for a human’.