July 24, 2024 – The eating habits you embrace in your 40s can significantly influence how you feel in your 70s and beyond – both physically and mentally.
A healthy diet not only reduces the risks of many chronic diseases but also leads to healthier aging, allowing you to enjoy a good quality of life and live independently for longer.
For instance, recent studies have shown that healthier eating across a variety of diets can lead to better living in later years. Several well-known diets were better at promoting healthy aging, including ones similar to the Dietary Guidelines for Americans, Mediterranean diet, and Dietary Approaches to Stop Hypertension (DASH) diet.
People who ate healthier in midlife, especially those whose diet is rich in fruits, vegetables, whole grains, and healthy fats, “were significantly more likely to achieve healthy aging,” said Anne-Julie Tessier, PhD, a research associate in nutrition at the Harvard T.H. Chan School of Public Health. She presented the study at the annual American Society for Nutrition meeting in July.
On the other hand, healthy aging was less likely in people whose diets were high in trans fats, sodium, and meat consumption in general, as well as red meats and processed meats in particular.
Tessier and colleagues examined data from more than 106,000 people between 1986 and 2016, and even after accounting for things like physical activity, tobacco use, and alcohol use, they found a link between a healthy diet and healthy aging overall, including physical health, thinking skills, and mental health.
“Traditionally, research and dietary guidelines have focused on preventing chronic diseases like heart disease,” she said. “Our study provides evidence for dietary recommendations to consider not only disease prevention but also promoting overall healthy aging as a long-term goal.”
Help Your Brain With Food
Eating a high-quality diet – one that closely aligns with the government’s 2020-2025 Dietary Guidelines for Americans – can also lead to better brain functioning and less decline in mental skills as you age.
In a study of 3,000 people followed for 7 decades, those with the highest cognitive abilities – or best thinking skills – over time tended to eat more vegetables, fruits, legumes, and whole grains. They also consumed less sodium, added sugars, and refined grains.
Overall, only 8% of people with low-quality diets had high cognitive ability later in life, while only 7% of people with high-quality diets had low cognitive ability. By ages 68-70, those in the highest cognitive group had better working memory, processing speed, and cognitive performance, yet those in the lowest cognitive group showed signs of dementia.
The earlier you start, the better. Dietary quality during childhood and the teen years seemed to influence food decisions later in life, building up the effects on brain health over time. Even so, it’s not too late to make changes now – many people in the study had steady improvements throughout adulthood as well.
“Adjusting dietary intake at any age to incorporate more high-quality foods and align more closely with current dietary recommendations is likely to improve our health in many ways, including our cognitive health,” said Kelly Cara, a recent PhD graduate in nutrition science at Tufts University in Massachusetts.
Cara and colleagues have shown that eating a diet with plant-based foods and high levels of antioxidants and monounsaturated and polyunsaturated fats can help the brain by improving blood flow and reducing oxidative stress, which can damage cells and cause inflammation and disease.
“Dietary patterns that are high in whole or less processed plant-food groups, including leafy green vegetables, beans, whole fruits and whole grains, may be most protective,” she said.
Nourish Your Heart and Mind
Changing your eating habits during midlife appears to boost health across the body.
Among 5,000 women enrolled in New York University’s Women’s Health Study, following a diet to lower blood pressure also led to fewer reports of memory loss or other signs of cognitive decline – even decades later.
Research has long found that high blood pressure is a risk factor for cognitive decline and dementia, particularly during our middle decades. But in this study, women who adopted the DASH diet in their late 40s were less likely in their late 70s to have cognitive complaints, such as forgetting recent events, shopping lists, or familiar streets.
“Our data suggest that it is important to start a healthy diet in midlife to prevent cognitive impairment in older age,” said Yixiao Song, lead author and an epidemiologist at the NYU Grossman School of Medicine. The study was published in October in the journal Alzheimer’s & Dementia.
Song noted key parts of the DASH diet, such as fruits, vegetables, nuts, and legumes, which are rich in potassium, calcium, and magnesium, as well as low in saturated fat, cholesterol, sodium, and sugar. Between ages 40 and 60, changing your habits to improve hypertension, diabetes, and obesity can reduce late-life brain cell breakdown and risks of Alzheimer’s disease as well, she said.
“Following the DASH diet may not only prevent high blood pressure but also cognitive issues,” Song said. “Mid-life may be a window of opportunity for lifestyle modifications to improve later life cognitive function.”
Choose Your Food Wisely
Instead of focusing on a particular diet, it’s important to look at the parts of a healthy meal and find out what’s best for you and your needs. In general, consuming protein in midlife appears to be key for a healthier older adulthood – but the source of the protein matters.
Based on data from more than 48,000 women in the Nurses’ Health Study, women who ate higher amounts of protein, especially from plant-based sources, developed fewer chronic diseases and were less likely to have heart disease, cancer, diabetes, cognitive decline, and mental health decline. They ate more protein found in fruits, vegetables, bread, beans, cereal, legumes, peanut butter, and pasta.
That’s the key, said Andres Ardisson Korat, doctor of science and lead author. Korat is a scientist at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University. The research was published in January in The American Journal of Clinical Nutrition.
Women who ate more plant-based protein were 46% more likely to be healthy in their later years, while those who ate more animal protein were 6% less likely to stay healthy as they got older.
Higher levels of plant protein coincided with lower cholesterol, blood pressure, and insulin sensitivity, and higher levels of animal protein were linked with higher cholesterol, blood pressure, insulin sensitivity, and insulin-like growth factor, which has been found in numerous cancers.
Notably, the differences may come from what’s inside the plant-based foods rather than the protein itself, Ardisson Korat said. Plants contain more fiber, micronutrients, and polyphenols that lead to better health. And protein in dairy products (such as milk, cheese, ice cream, pizza, and yogurt) weren’t necessarily linked to better health in older adulthood, which brings up questions for future studies, he said.
In general, though, Ardisson Korat recommended a midlife diet with fruits, vegetables, nuts, and seeds, as well as some fish and animal protein for iron and vitamin B12.
“Dietary protein intake, especially plant protein, in midlife plays an important role in the promotion of healthy aging and in maintaining positive health status at older ages,” he said.
