Jan. 18, 2024 – Getting just a little more protein from plant sources than from animal sources was linked to significantly higher odds of overall healthy aging among women, according to a large new study that followed people from middle to older age.
The results showed that every 3% of calories swapped for plant-based protein from animal-based options was linked to increased odds of avoiding declines in thinking skills , mental and physical health, and staying free from 11 serious health problems like type 2 diabetes and heart attacks.
The findings were published this week in The American Journal of Clinical Nutrition. Researchers analyzed health and diet information from a databank developed from the Nurse’s Health Study, which followed female health professionals from 1984 to 2016. The health professionals whose data was used for this study ranged from 38 to 59 years old at the start of the study and didn’t have any physical or mental health problems at the outset.
Of the 48,762 women who were under age 60 and healthy in 1984, 7.6% were still considered healthy 30 years later. The researchers defined healthy aging as having good mental health, not having thinking or physical problems, and being free from 11 major chronic diseases, including type 2 diabetes, Parkinson’s disease, kidney failure, heart attack, stroke, heart failure, and other common conditions that affect the heart and blood vessels.
Overall, nearly 1 in 3 women in the study remained free of any of the 11 chronic diseases, and nearly half of the women didn’t report any memory problems. But about 85% of the women did develop physical function limitations, and nearly two-thirds did not maintain good mental health status.
“Consuming protein in midlife was linked to promoting good health in older adulthood,” lead study author Andres Ardisson Korat, DSc, a scientist at Tufts University’s Jean Mayer USDA Human Nutrition Research Center on Aging, said in a news release. “We also found that the source of protein matters. Getting the majority of your protein from plant sources at midlife, plus a small amount of animal protein seems to be conducive to good health and good survival to older ages.”
The researchers specifically looked at protein intake because prior studies have linked it with physical functioning, including limiting muscle loss and even reducing the risk of hip fractures and bone loss.
The analysis included estimates of how much protein the women in the study ate based on their answers to questions about what they ate or drank as part of periodic surveys. The women reported how often they ate a food, ranging from “never or less than once per month,” to “6 or more times per day.” The most common animal-based protein sources the women reported consuming were beef, chicken, milk, fish, and cheese. The most common plant sources were bread, vegetables, fruits, pizza, cereal, baked items, mashed potatoes, nuts, beans, peanut butter, and pasta.
Total protein intake or simply protein intake from dairy sources had no impact on the odds of healthy aging, the analysis showed. Eating animal protein was linked with 6% lower odds of healthy aging, while eating plant proteins were linked to 46% higher odds of healthy aging.
The researchers decided to look at protein based on these types because animal-based proteins consumed during middle age are linked to higher rates of dying from health issues like heart disease, they said
The authors cautioned that the women in the study were mostly White, and further study is needed among a more diverse population in order to generalize the results to other populations.