Among adults over 80, diet quality and maintaining a healthy weight matter more for longevity than whether meat is eaten.
A recent study suggests that people who avoid meat may be less likely than meat eaters to live to 100. Before viewing this as a warning about plant-based diets, however, the results deserve a closer look.
The researchers followed more than 5,000 adults in China who were aged 80 and older and took part in the Chinese Longitudinal Healthy Longevity Survey, a nationally representative project that began in 1998. By 2018, participants whose diets excluded meat were less likely to reach centenarian status than those who ate meat.
At first glance, this finding seems to clash with a large body of evidence linking plant-based diets to better health. Vegetarian eating patterns have repeatedly been associated with lower risks of heart disease and stroke, type 2 diabetes, and obesity, benefits often attributed to higher fiber intake and lower levels of saturated fat.
So how can these results be explained? Several key factors need to be considered before drawing broad conclusions about diet and longevity from this study.
Your body’s needs change as you age
This study focused on adults aged 80 and older, whose nutritional needs differ markedly from those of younger people. As we age, physiological changes alter both how much we eat and what nutrients we need. Energy expenditure drops, while muscle mass, bone density, and appetite often decline. These shifts increase the risk of malnutrition and frailty.
Most evidence for the health benefits of diets that exclude meat comes from studies of younger adults rather than frail older populations. Some research suggests older non-meat eaters face a higher risk of fractures due to lower calcium and protein intake.
In later life, nutritional priorities shift. Rather than focusing on preventing long-term diseases, the goal becomes maintaining muscle mass, preventing weight loss, and ensuring every mouthful delivers plenty of nutrients.
The study’s findings may, therefore, reflect the nutritional challenges of advanced age, rather than any inherent problems with plant-based diets. Crucially, this doesn’t diminish the well-established health benefits of these diets for younger and healthier adults.
Body weight explains much of the risk
Here’s a crucial detail: the lower likelihood of reaching 100 among non-meat eaters was only observed in underweight participants. No such association was found in older adults of healthy weight.
Being underweight in older age is already strongly linked with increased risks of frailty and death. Body weight, therefore, appears to be a key factor in explaining these findings.
It’s also worth remembering that this was an observational study, meaning it shows associations rather than cause and effect. Just because two things occur together doesn’t mean one causes the other.
The findings also align with the so-called “obesity paradox” in aging, where a slightly higher body weight is often linked to better survival in later life.
Notably, the reduced likelihood of reaching 100 observed among non-meat eaters was not evident in those who included fish, dairy, or eggs in their diets. These foods provide nutrients that are essential for maintaining muscle and bone health, including high-quality protein, vitamin B12, calcium, and vitamin D.
Older adults following these diets were just as likely to live to 100 as meat eaters. The researchers suggested that including modest amounts of animal-source foods may help prevent undernutrition and loss of lean muscle mass in very old age, compared with strictly plant-based diets.
What this means for healthy aging
Rather than focusing on whether one diet is universally better than another, the key message is that nutrition should be tailored to your stage of life. Energy needs decline with age (due to decreased resting energy expenditure), but some nutrient requirements increase.
Older adults still require adequate protein, vitamin B12, calciu,m and vitamin D – especially to preserve muscle mass and prevent frailty. In older adulthood, preventing malnutrition and weight loss often becomes more important than long-term chronic disease prevention.
Plant-based diets can still be healthy choices, but they may require careful planning and, in some cases, supplementation to ensure nutritional adequacy, particularly in later life.
The bottom line is that our nutritional needs at 90 may look very different from those at 50, and dietary advice should reflect these changes across the lifespan. What works for you now might need adjusting as you age – and that’s perfectly normal.
Reference: “Vegetarian diet and likelihood of becoming centenarians in Chinese adults aged 80 y or older: a nested case-control study” by Yaqi Li, Kaiyue Wang, Yuebin Lv, Guliyeerke Jigeer, Yilun Huang, Xiuhua Shen, Xiaoming Shi and Xiang Gao, 12 December 2025, The American Journal of Clinical Nutrition.
DOI: 10.1016/j.ajcnut.2025.101136
Adapted from an article originally published in The Conversation.
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5 Comments
This is not about the results of a study, but an editorial to rationalize away the results of the study. Recommending meat goes against the grain of the vegetarian mindset. There is also an interesting statement made. “In later life, nutritional priorities shift. Rather than focusing on preventing long-term diseases, the goal becomes maintaining muscle mass, preventing weight loss, and ensuring every mouthful delivers plenty of nutrients.” I suppose that means that you can start to smoke and drink once you get old. No need to worry about long-term disease forming when you don’t have a long-term to live. Interesting approach to aging.
“This is not about the results of a study, but an editorial to rationalize away the results of the study.”
I’m almost certain that is only your personal opinion because you provide no counter evidence or citations that support your statement and there is no obvious way that you could be privy to the motivation or thinking of the authors. In short, YOU are rationalizing disagreeing with an observational study.
“I suppose that means that you can start to smoke and drink once you get old.”
That is an illogical claim because the topic of discussion was nutritional needs. Smoking is not an activity that provides nutrition, and the nutrition from alcoholic beverages is only incidental to its consumption. Fermentation was probably an accidental discovery of an overabundance of seasonal foods for which people tried to stretch out the availability. Waterborne pathogens were not normally present in the fruit or its juices, and were usually killed by the alcohol if diluted with the usual unsafe drinking water. It thus was an important way to obtain safer, potable water. Subsequent to that, most people decided that they also enjoyed the way they felt. They did not drink alcoholic beverages to sate their hunger. That is still essentially true. One drinks a glass of chardonnay with their Chateaubriand; they don’t fill up on the wine.
Clyde, the article clearly favors plant-based diets. It assumes that people might be alarmed by the suggestion that meat is beneficial. The article’s second sentence essentially tells readers not to worry about the findings. This framing decision—leading with reassurance rather than the study results—reveals the author’s priorities. If you agree with those priorities, then this seems balanced. To me, the bias was evident. The article gave a spin on the study, instead of just presenting the study. Starting with “Before viewing this as a warning about plant-based diets, however, the results deserve a closer look” is advocacy language. A more neutral approach would present the findings first, then explore interpretations. The article assumes readers will be pro-plant-based and need reassurance. This assumption itself reveals bias about who the intended audience is and what they believe. The article is actively managing how readers should feel about the findings rather than letting them draw their own conclusions from a straightforward presentation.
I would say that the article does not favor plant-based diets. It writes “Notably, the reduced likelihood in reaching 100 observed among non-meat eaters was not observed among those who ate fish, dairy, or eggs in their diet.” That is not an exclusively plant-based diet. Eggs are laid by animals, dairy comes from milk which comes from mammals, and fish are animals. Clearly foods like that are needed, when you don’t eat meat from mammals or birds. Vegan type diet is not adequate enough to provide certain nutrients. I do not like the taste of meat, but I eat fish, dairy, and eggs. Those foods taste much better for me. So I do not eat a plant-based diet, but a mixed diet, which includes some plants too; And I like the taste of the foods I eat.
No one needs to routinely eat a 16 oz steak at dinner. Unless someone creates a microbe that produces enough B12 to supply the need for that nutrient, humans do need some meat. I heard a nutritionist say that meat doesn’t really need to be the entree, and using it as a garnish would be adequate. Is it possible that older people who are vegetarian tend to forget their B12 supplement?