A Healthy Diet in Your 40s Can Pay Off When You're 70

Key Takeaways

• A new study found that women who followed a healthy diet from their forties onward were 43 to 84 percent more likely to be well-functioning physically and mentally at age 70.
• Only about 1 in 10 women "aged well" by the end of the study, the researchers said.
• Good dietary habits can prevent chronic diseases and improve energy and mood.

New research presented this week at the annual meeting of the American Society for Nutrition in Chicago found that a nutritious diet begun in a person's forties may foster healthy aging and independent living decades later.

"People who adhered to healthy dietary patterns in midlife - especially those rich in fruits, vegetables, whole grains, and healthy fats - were significantly more likely to achieve healthy aging," says an author of the study, Anne-Julie Tessier, PhD , a postdoctoral fellow at the Harvard T.H. Chan School of Public Health. "We were surprised at the strength of this association even after considering several other factors, like physical activity, that are also known to impact health."

Dr. Tessier and her colleagues analyzed data going back to 1986 on more than 106,000 women. Subjects at the start of the review were at least 39 years old and free of any chronic diseases.

The researchers observed that the women who followed a healthy diet from their forties onward were 43 to 84 percent more likely to be well-functioning physically and mentally at age 70 than those who did not.

Healthy aging was defined as surviving to age 70 or beyond while maintaining good self-reported cognitive function, physical function, mental health, and absence of chronic disease until the study's completion, in 2016. Only about 1 in 10 women (9.2 percent) reached this benchmark.

Reporting 1 or fewer depressive symptoms out of 15 - such as not feeling energetic or often feeling bored - was the metric for good mental health, while one or fewer physical limitations, such as not being able to climb one flight of stairs or walk one block, was considered good physical function.

Every four years over the course of the study, participants completed questionnaires providing information about their eating habits. At the end of the study, in 2016, higher intakes of fruits, vegetables, whole grains, unsaturated fats, nuts, legumes, and low-fat dairy were positively associated with greater odds of healthy aging; and higher intakes of trans fat, sodium, total meats, and red and processed meats were inversely associated.

It's Never Too Late to Get a Boost From Good Nutrition

For Janna Assar, MD , a family medicine physician with Banner Health in Phoenix, this latest study backs up previous research demonstrating the benefits of adopting healthier eating habits.

"Dietary choices made in midlife have a lasting impact on health and well-being in older age," says Dr. Assar, who was not involved in the study. "A nutritious diet can help prevent chronic diseases such as heart disease, diabetes, and cognitive decline, contributing to healthier aging. Following a healthy diet can also lead to improved energy levels, better physical function, and enhanced mental clarity in later life."

Although this study focuses on positive health effects gained over decades, Assar stresses that it's never too late to get a boost from better nutrition.

"While early adoption of healthy eating habits is ideal, making positive dietary changes at any age can still provide significant health benefits," she says.

These benefits include improvements to energy level, mood, increased longevity, increased quality of life, and reduced inflammation.

Assar adds that a healthier diet may even help seniors potentially reverse certain chronic conditions, such as hypertension, type 2 diabetes, and high cholesterol, regardless of how old they are when they revamp their eating habits.

The Alternative Healthy Eating Index Came Out on Top

Tessier and her team looked at eight different nutritious eating programs. The one that came out on top was the Alternative Healthy Eating Index, developed at Harvard. Researchers found that this eating pattern had the strongest correlation with healthy aging. People who adhered to this diet most closely were 84 percent more likely to achieve healthy aging than those who were least able to stick to this eating pattern.

The researchers also found strong correlations for the following diets:

• Empirical dietary index for hyperinsulinemia diet (associated with a 78 percent greater likelihood of healthy aging)
• Planetary health diet (68 percent)
• Alternative Mediterranean diet (67 percent)
• DASH (dietary approaches to stop hypertension) diet (66 percent)
• MIND (Mediterranean-DASH intervention for neurodegenerative delay) diet (59 percent)
• Empirical dietary inflammatory pattern (58 percent)
• Healthful plant-based diet (43 percent)

The researchers found the association between the planetary health diet and healthy aging to be of particular interest.

"This diet, which minimizes animal products and emphasizes fruits, vegetables, whole grains, and healthy fats, emerged as one of the leading dietary patterns associated with healthy aging," says Tessier. "This is particularly interesting because it suggests that we can eat a diet that benefits both human health and environmental sustainability."

The researchers pointed out that they did not not look at differences between how long people followed healthy diets and how well they aged. They also did not look at the likelihood of chronic disease or death in relation to sticking to a particular diet.

Given the study's focus on dietary patterns in middle age, Tessier says that future research could focus on the potential impacts of switching to a healthier dietary pattern even later in life.

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