BOSTON — Surprise, surprise. Eating healthy and improving your diet over an extended period of time can help you avoid death and chronic illness in later life, a new study finds.

Researchers at Harvard looked at data from two longitudinal studies, which had nearly 74,000 combined participants, in an attempt to examine the aftereffects of an improved diet over an extended period of time.

Man holding a salad
Eating healthy and improving your diet over an extended period of time can help you avoid death and chronic illness in later life, a new study finds.

First, the researchers examined participants’ diet quality over a 12-year period. Three metrics were used to gauge one’s quality of diet: the 2010 Alternate Healthy Eating Index, the Alternate Mediterranean Diet score, and the Dietary Approaches to Stop Hypertension (DASH) diet score.

On each of these three dietary scales, a higher score represents a more healthy regimen.

The researchers then sought to determine how participants’ risk of dying over the subsequent 12 years was affected by their scores to give the team insight on the before and after impact of a diet.

Overall, individuals whose diets were comprised of healthy comestibles — e.g., whole grains, fruits, nuts, vegetables, and fish — over the 12 years examined, had a reduced risk of death the 12 years following.

Delving into the numbers, a 20-percentile increase in diet quality was linked to anywhere from an 8 to 17 percent decrease in likelihood of death.

The researchers noted that substituting a single serving of red meat for legumes or nuts could achieve this outcome.

“Our study indicates that even modest improvements in diet quality could meaningfully influence mortality risk and conversely, worsening diet quality may increase the risk,” says lead author Mercedes Sotos-Prieto in a university news release.

Even individuals whose scores started out poorly, but improved over the course of the study, noticed significant gains.

The authors also discovered there was an inverse relationship between health and diet for those who ate poorly, with worsened diets raising the odds of death by 6 percent to 12 percent.

“Our results highlight the long-term health benefits of improving diet quality with an emphasis on overall dietary patterns rather than on individual foods or nutrients,” says senior author Frank Hu. “A healthy eating pattern can be adopted according to individuals’ food and cultural preferences and health conditions. There is no one-size-fits-all diet.”

The study’s findings were published July 13 in the New England Journal of Medicine.

About Daniel Steingold

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