Eating healthy in your 40s may help you stay mentally and physically fit in your 70s.

New research published in the journal Nature Medicine found that people who followed one of eight healthy dietary patterns in midlife had a 45% to 86% greater chance of healthy aging. Eating more ultra-processed foods was associated with a 32% lower chance of healthy aging.

The researchers defined healthy aging as hitting age 70 free from chronic disease—like diabetes and most types of cancer—while maintaining physical, mental, and cognitive function. 

“Essentially, midlife is a critical window where dietary changes can significantly impact both short- and long-term health and independence as we all age,” said Angel Planells, MS, RDN, a Seattle-based registered dietitian nutritionist and national media spokesperson for the Academy of Nutrition and Dietetics.

Of the eight dietary patterns included in the study, the Alternative Healthy Eating Index (AHEI) was found to have the strongest association with healthy aging. Diets high in red and processed meats, sugary beverages, trans fat, and sodium had the opposite effect.

“The healthy diets we examined share common principles, such as being rich in vegetables, fruits, whole grains, and healthy fats,” said Anne-Julie Tessier, RD, PhD, the first author of the study and an assistant nutrition professor at the University of Montreal.

What Is the Alternative Healthy Eating Index?

The Alternative Healthy Eating Index was developed in 2002 as a tool to help lower chronic disease risk.

Following a dietary pattern that rates high on the AHEI was associated with an 86% chance of healthy aging at 70 and a 2.24 times greater chance of healthy aging at 75, according to the new study.

It’s a flexible dietary pattern that works across all cultural cuisines and is plant-centered but not strictly vegetarian or vegan, according to Judy Simon, MS, RDN, FAND, a clinical dietitian nutritionist at the UW Medical Center.

“This dietary pattern focuses on food intake patterns high in fruits, vegetables, whole grains, legumes, nuts, unsaturated fats, along with a reduction in processed and red meats, refined grains, and sugar-sweetened beverages,” Simon told Verywell.

For a more AHEI-friendly diet, try to eat five servings of vegetables, extra leafy greens, four fruit servings, five to six whole grain servings, and one serving of nuts, legumes, or tofu daily. Also, aim to consume fish and healthy fats throughout the week.

Why Does Your Midlife Diet Support Cognitive Function Later?

It’s never too late to start eating a nutrient-rich diet, but research shows that eating a healthy diet in midlife plays an especially important role in healthy aging.

“As a person ages and enters their 40s and 50s, biological aging begins to accelerate, and the risk of chronic diseases—heart disease, diabetes, cognitive decline—begins to rise,” Planells said.

Adding whole grains, fruits, vegetables, and other anti-inflammatory, nutrient-dense foods to your diet can help support gut health, protect brain function, maintain muscle and bone strength, and lower cholesterol, he added.

A 2023 study published in the journal Alzheimer’s & Dementia found similar results with the Dietary Approaches to Stop Hypertension (DASH) diet. Following this diet in midlife was associated with fewer reports of cognitive issues as the participants aged.

“A healthy diet during midlife can reduce inflammation and oxidative stress, which are linked to high blood pressure and cardiovascular disease—major risk factors for cognitive impairment,” Yu Chen, MPH, PhD, senior author of the 2023 study and a professor in the department of population health at NYU Langone Health, told Verywell.

The DASH diet, which was also one of the eight healthy diets included in the Nature Medicine study, helps lower blood pressure. It includes fruits, vegetables, whole grains, fish, vegetable oils, low-fat or fat-free dairy, poultry, beans, and nuts.

How to Take Care of Yourself as You Age

Following a healthy diet does not automatically mean you will grow old without developing chronic diseases. Many things impact aging, like genetics and social and environmental factors, which are out of your control.

Still, incorporating more nutrient-dense foods into your diet may help keep you healthy. “Staying active, fueling your body with good nutrition, and taking care of other things can lead to a high quality of life as a person ages,” said Planells.