According to research published in the journal Science Advances, a healthy diet may be associated with up to 4.3 additional years of life for men and 3.2 years for women.
This applied to individuals who followed the Alternative Healthy Eating Index.
Other dietary patterns also showed a positive association.
The Diabetes Risk Reduction Diet was linked to around three extra years for men and 1.7 years for women.
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The Mediterranean diet showed a difference of just over two years for both sexes.
A plant-based diet and the DASH diet resulted in smaller, yet still measurable, differences of around two years or less.
More than 100,000 participants
The findings are based on data from more than 100,000 individuals in the UK Biobank, a large British health study containing genetic and medical information.
Participants were followed for just over ten years. They regularly reported what they had eaten during the previous 24 hours. During the study period, 4,314 people died.
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Researchers compared dietary habits, deaths, and 19 genetic variants that have previously been linked to longevity.
Diet matters
The study shows that the association between a healthy diet and a longer life applied regardless of genetic risk. In other words, genes alone could not explain the difference.
Foods such as whole grains, fruit, and vegetables showed the clearest link to longer life expectancy, according to the researchers.
Sources: Medical Xpress, and Science Advances.
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