What you eat has long been linked to better health and even extending lifespan. But when you eat may be just as important when it comes to boosting longevity.
A 2025 study published in Nature found that a later breakfast start time is associated with increased mortality.
Researchers followed the health of 2,945 older adults over several decades from the University of Manchester Longitudinal Study of Cognition in Normal Healthy Old Age. At the start of the study, when participants were on average 64 years old, the typical breakfast time was 8.22am but this got later as time went on.
For each additional hour of delayed breakfast timing was associated with an 8–11% higher risk of death.
The 10-year survival rate was 86.7 per cent for those in the late eating group compared to 89.5 per cent in the early breakfast group.
Russell Foster, a professor of circadian neuroscience at the University of Oxford, says that timing meals to sync with the 24-hour body clock is a good way to remain healthy for longer and that people should try to eat a bigger breakfast earlier in the day and a smaller evening meal around 6pm.
‘That’s because the stomach empties faster, after identical meals, in the morning than in the evening, for example. And colon contraction is much slower during the night., which makes digestion slower and less efficient.’
Circadian rhythms naturally reduce insulin sensitivity and pancreatic activity at night, meaning your body handles carbohydrates much less efficiently late in the day.
‘We now appreciate that the same meal consumed at different times of the day can produce very different levels of blood glucose due to the circadian-drive changes in glucose uptake and metabolism,’ said Professor Foster.
‘Importantly, the same meal in the evening results in higher levels of blood glucose compared to identical meals that are eaten in the morning.’
Avoiding obesity is also very important for remaining healthy for longer.
Over time, he said, these elevated blood glucose levels can lead to chronic insulin resistance, raising the risk of developing or worsening type 2 diabetes and cardiovascular damage.
Avoiding obesity is also very important for remaining healthy for longer.
Obesity accelerates telomere shortening, which is the progressive reduction in the length of telomeres, the protective structures at the ends of chromosomes which become shorter during the ageing process. Shorter telomeres make cells stop dividing or die, which triggers tissue inflammation and increases the risk of age-related and degenerative diseases
Multiple studies have shown that there is a link between obesity and shorter telomere length.
Oxidative stress and inflammation are potential mechanisms by which obesity leads to telomere shortening. Fat cells release inflammatory compounds that damage sensitive telomeres. Inflammation signals cells to divide more frequently to replace damaged tissue. Every time a cell divides, its telomeres naturally shorten.
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- Eat on time for a longer life - October 2, 2026
