Adults who stick to diets rich in plant-based foods, and eat fewer ultra-processed foods, have a higher likelihood of reaching their 70th birthday free of major chronic disease. Photo / 123RF
Adults who stick to diets rich in plant-based foods, and eat fewer ultra-processed foods, have a higher likelihood of reaching their 70th birthday free of major chronic disease. Photo / 123RF
Diets rich in plant-based foods, and fewer ultra-processed foods, is associated with healthy aging, a study has found.
What you eat in your 40s, 50s and 60s may affect how healthy you are at age 70.
Adults who stick to diets rich in plant-based foods, andeat fewer ultra-processed foods, in those middle decades of their lives, have a higher likelihood of reaching their 70th birthday free of major chronic disease, a study published Monday found.
The 30-year study, which followed the eating habits of more than 100,000 middle-aged adults, found that diets with comparatively higher amounts of plant-based foods – fruits, vegetables, whole grains, unsaturated fats, nuts and beans – were associated with a higher likelihood of healthy ageing.
“This suggests what you eat in midlife can play a big role in how well you age,” said Anne-Julie Tessier, an assistant professor of nutrition at the University of Montreal and the lead author of the observational study, which was published in Nature Medicine.
The team of researchers from the Harvard T.H. Chan School of Public Health, University of Copenhagen and University of Montreal defined “healthy ageing” as living to age 70 free of chronic disease such as diabetes and congestive heart failure, with positive marks on measures of cognitive, physical and mental health. In the study, 9771 of the participants achieved healthy ageing.
Most older adults have at least one chronic health condition. Previous studies have found diets that emphasise plant-based foods, and less red or processed meat, can lower the risk of cardiovascular disease and all-cause mortality. But, in this study, researchers set out to understand if these dietary guidelines could also enhance the quality of someone’s life in old age.
The facts
The researchers examined the long-term, self-reported dietary patterns of 105,015 middle-aged U.S. health professionals from 1986 to 2010 and then evaluated them for markers of healthy aging in 2016.
Every four years, participants reported how often they ate more than 130 different foods. The researchers then measured how closely each person adhered to eight healthy diets, such as the Mediterranean diet, which prioritizes fruits, vegetables and olive oil.
A higher adherence to any of the eight dietary patterns was associated with greater odds of healthy aging. These diets had comparatively more fruits, vegetables, whole grains and unsaturated fats, nuts, legumes and low-fat dairy.
Diets higher in trans fats, sodium, sugary beverages and red or processed meat were associated with a lower likelihood of healthy aging. And participants who consumed the most ultra-processed foods had 32 percent lower odds of healthy aging.
The positive associations of diet and aging were independent of other lifestyle factors, including physical activity, smoking and a person’s body mass index.
Adherence to the Alternative Healthy Eating Index, a scoring system developed by nutrition experts at the Harvard T.H. Chan School of Public Health and one of the eight dietary patterns used in the study, showed the strongest association with healthy aging at age 70. A healthful plant-based diet, which did not include animal-based foods, had the weakest association.
One of the authors of the study, Marta Guasch-Ferré, is the principal investigator of a grant funded by the International Nut Council, an association for the industry.
The study looked at decades-long trends in people’s diets. The eight dietary patterns researchers compared generally prioritise fruits, vegetables, whole grains and unsaturated fats, and have less red or processed meat.
The dietary patterns are the Alternative Healthy Eating Index, the Alternative Mediterranean Index, the Dietary Approaches to Stop Hypertension (DASH), the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND), a healthful plant-based diet, the Planetary Health Diet Index, the empirically inflammatory dietary pattern and the empirical dietary index for hyperinsulinemia.
A “high” score in the Alternative Healthy Eating Index translates to eating a serving of fish once per week and at least five servings of vegetables, four servings of fruit, five to six servings of whole grains and one serving of nuts or beans per day, Tessier said.
Meanwhile, the Mediterranean diet used in the study prioritises olive oil, fish and nuts. And the MIND diet focuses on berries. But the findings show “there’s no one-size-fits-all approach” for the healthiest diet, said Tessier, who’s also a researcher at the Montreal Heart Institute. People can take into account their personal preference for certain types of foods, she said.
What other experts say
Lars Fadnes, a professor of global public health at the University of Bergen in Norway, said the study’s findings are “very well aligned” with other research of plant-based diets.
Fadnes has led multiple studies showing that sustained changes in a person’s diet – to include more whole grains, nuts, beans and less red or processed meat – can lead to substantial gains in life expectancy.
“That doesn’t mean that fruits and vegetables aren’t as important,” Fadnes said. “Rather, it means, for many, their original diet is a little further away for legumes and nuts.”
Maura Walker, an assistant professor of health sciences and medicine at Boston University, said for most people it’s about “inching up” their diet towards these targets.
“For most people, we’re not achieving that target,” Walker said. “When I look at my data, I see most people aren’t eating any legumes.”
The Mediterranean diet prioritises olive oil, fish and nuts. Photo / 123RF
The limitations of the study
The study is observational, meaning the findings don’t establish a cause-and-effect relationship. The researchers found an association between healthy eating patterns and a lower likelihood of chronic disease at age 70. But a reverse association is possible; it could be that a change in a person’s health affected their eating habits, Tessier said.
The researchers examined the diets of US health professionals, and the findings might not be applicable to a broader population.
The diets were also self-reported. Other researchers have found people can be unreliable at reporting what they eat day-to-day. But Tessier said the questionnaire responses were “extensively validated,” and the study’s large sample size followed over three decades “increases our confidence” in the results.
