Registered dietitian Sophie Medlin has revealed the ideal times to eat breakfast, lunch and dinner, as a growing body of research suggests eating most of your calories earlier in the day could speed up weight loss, lower blood pressure and keep you fuller for longer.
Medlin said the body's ability to use food depends on its interaction with a person's daily routine, including when they wake up, sleep and exercise.
Last year, scientists in Slovenia found that restricting meals to an 8am to 4pm window led to ten pounds of weight loss over three months, along with a reduction in body fat and stabilised blood sugar levels. Critics argue the effect is simply the result of fitting fewer calories into a shorter window.
Is eating earlier really better?
"There's no denying that research suggests eating more of our energy earlier in the day could produce some benefits for weight and heart health," Medlin said.
She pointed to a 2024 meta-analysis, described as perhaps the most in-depth study on the subject, which found that earlier calorie distribution and time-restricted eating produced reductions in weight, albeit relatively small.
"Our bodies run on approximately 24-hour circadian rhythms," Medlin said. "These influence how good our body is at converting blood sugar to energy and digesting food, as well as the level of our appetite hormones."
She explained that the body is generally more efficient at converting sugars in food into energy, and therefore burning calories, during the most active part of the day. "Eating earlier gives us more opportunity to use energy through movement," she added.
A 2022 Harvard study asked 16 overweight and obese adults to follow an early eating schedule for two weeks, then pushed their meals back by four hours while keeping the same calorie intake. Early eaters had their first meal about one hour after waking, around 8am on average, while late eaters waited five hours, with some not eating until as late as 12pm. The early group ate dinner around 4.30pm, compared with 8.30pm for the late group.
The results showed that those on the later schedule had much higher blood levels of hormones associated with hunger, and lower levels of compounds released in response to fullness. The researchers concluded that eating later could trigger changes in the gut that increase hunger signals, raising the risk of weight gain.
Medlin cautioned that the study involved only 16 adults and that "more conclusive evidence is needed to prove the theory." She acknowledged, however, that delaying most food until late evening could disrupt appetite regulation and cause blood sugar levels to go awry.
What about skipping breakfast?
Intermittent fasting, which involves limiting calorie intake for a few days a week, remains popular in Britain. Most people who follow it skip breakfast and save their calories for lunch and dinner, while cutting out snacks.
A review published earlier this year suggested the approach could reduce body weight by about 3 per cent, roughly five and a half pounds for an average man. But a wealth of other reviews have found the benefits are likely just the result of eating fewer calories overall, with scientists reporting similar weight loss from other low-calorie diets.
Some research suggests skipping breakfast could cause people to overeat later. One large observational study of the dietary records of 23,488 American adults found that people who skipped both breakfast and lunch consumed, on average, about 187 more calories at dinner.
Another study, involving almost 3,000 older adults, found that delaying the first meal of the day by even an hour was linked to an 11 per cent higher risk of death.
"Skipping breakfast risks a pattern whereby you eat very little throughout the day and then consume a large proportion of the day's food late at night," Medlin said. "This can encourage overeating, and large, rich meals close to bed may cause reflux, bloating or disturbed sleep."
She added that because the body is less able to convert food to energy at night, excess calories eaten late are more likely to be stored as fat.
Is there an optimum time for every meal?
Medlin said there are no specific timings that guarantee a person won't overeat, become sluggish or lose focus. However, she said there are "useful windows" to stick to, based on the strongest scientific evidence.
"Breakfast could be eaten within around one to two hours of waking up, lunch approximately four to five hours later, and dinner ideally two to three hours before bed," she said. "For someone following a conventional sleep pattern, that might mean breakfast between 7am and 9am, lunch between 12pm and 2pm, and dinner between 6pm and 8pm."
Medlin said the most crucial point is making sure the hours before bed are not the main eating period of the day. "Finishing a main meal approximately two to three hours before lying down is a sensible target. This provides time for digestion and can reduce reflux or discomfort."
