Eating healthy now could set you up for a better life in the future: A diet high in fruits, vegetables, whole grains and unsaturated fats in midlife may improve your chances of having good mental, physical and cognitive health decades later, a new report shows.
The study, presented at a major nutrition conference on Tuesday, builds on years of research showing that a daily diet rich in nutritious foods can reduce the risk of developing common chronic diseases and help preserve cognitive function in older age.
Harvard researchers analyzed 30 years’ worth of data from more than 106,000 participants in the Nurses’ Health Study and the Health Professionals Follow-up Study. The studies included 70,467 women and 36,464 men. At the start of the study in 1986, participants were 39 years of age or older and free of chronic diseases.
As part of the long-term study, participants completed extensive food-frequency questionnaires every four years from 1986 to 2010, said lead author Anne-Julie Tessier, R.D., a research fellow at the Harvard School of Public Health.
Harvard researchers tracked each participant’s personal eating habits over time to see how well they followed eight nutritious eating patterns.
The diets they compared in their food questionnaire included:
- The DASH diet is an eating plan that focuses on vegetables, fruits, and whole grains to prevent or lower blood pressure. Developed by the National Institutes of Health, this eating plan is considered a flexible diet because it doesn’t eliminate any food groups and can also help with weight loss.
- The Alternative Healthy Eating Index (AHEI) closely follows the US Dietary Guidelines, including recommending more legumes, nuts and vegetables and less red and processed meat, and Tessier said the study found the strongest correlation between the AHEI diet and healthy aging.
- The Planetary Health Diet is an eating plan that minimizes animal products and emphasizes fruits, vegetables, whole grains, and healthy fats. Moderate amounts of meat and dairy products are also allowed.
Overall, the higher the intake of fruits, vegetables, whole grains, unsaturated fats, nuts, legumes and low-fat dairy products, the more likely one is to age healthily. People who consumed diets higher in trans fats, sodium and red and processed meats were less likely to age healthily.
What is “healthy aging”?
Based on self-reporting by the women and men in their database, the researchers interpreted “healthy aging” as living to at least age 70, having good cognitive function, mental health, and physical function, and being free of chronic diseases such as diabetes, heart disease, stroke, kidney failure, and most cancers.
After analyzing 30 years of data, the researchers found that about half of the participants died, and only 9% survived to age 70 or older, free of disease and in good physical and cognitive health.
However, participants who adhered most closely to healthy eating patterns were 43% to 84% more likely to age healthily than those who did not.
What you eat now affects how you feel later
The new study has limitations. Like most nutrition research, it’s observational and based on self-reporting. It doesn’t prove that strictly following a nutritious dietary pattern will help you live longer or be healthier in old age. It hasn’t been published in a journal yet, but it’s currently undergoing peer review, Tessier said.
But numerous studies have already demonstrated that diet and exercise can reduce the risk of all of these diseases and improve the chances of “healthy aging,” said Dr. R. Sean Morrison, chief of Brookdale Geriatrics and Palliative Medicine at Mount Sinai Hospital.
“It’s important to take into account that people who eat healthy diets are also more likely to be physically active, more likely to live in socially advantaged areas, have access to supports and better access to health care that others don’t,” said Morrison, who was not involved in the new study.
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Indeed, Tessier noted, the researchers analyzed variables that could have influenced the results, including BMI, ancestry, smoking status, alcohol intake, physical activity, medical and family history, socioeconomic status, marital status, and whether participants lived alone.
“We were surprised to see such a strong association between healthy eating habits in midlife and healthy living later in life, even after accounting for several other factors known to influence health, such as physical activity,” she added.
Lawrence Appel, a professor at the Johns Hopkins University School of Medicine who was not involved in the study, said the findings support previous research. Appel’s research focuses on preventing chronic disease through nutritional approaches and is lead author of the study that coined the DASH diet.
“This study joins a growing body of research showing that healthy eating habits in youth lead to improved health decades later,” he said.
For Mount Sinai’s Morrison, “the fundamentals of healthy aging are eating a healthy diet, exercising, avoiding tobacco products, using sunscreen, getting enough sleep, and participating in social activities. This has been known for a long time.”
