For years, plant-based diets have been praised for lowering the risk of major diseases such as heart disease, stroke, obesity, and type 2 diabetes. That is why a recent study out of China has surprised many researchers by suggesting that, under certain circumstances, older adults who eat meat may be more likely to live to 100 than strict vegetarians. But before anyone rushes to abandon vegetables for steak, researchers and nutrition experts say there is an important catch.
The research comes from one of the largest studies of older adults in the world, the Chinese Longitudinal Healthy Longevity Survey (CLHLS), a nationally representative study that began in 1998. Researchers from institutions including Fudan University, the Chinese Center for Disease Control and Prevention, and Shanghai Jiao Tong University examined the diets and outcomes of more than 5,200 adults aged 80 and older to better understand what helps people achieve exceptional longevity.
The study followed 5,203 adults over age 80 and compared the outcomes of 1,459 people who reached age 100 with 3,744 people who died before becoming centenarians. Researchers classified participants based on diet, including meat eaters, vegetarians, and vegetarian subgroups such as people who ate fish, dairy, or eggs. They then analyzed whether dietary patterns were linked to the odds of surviving to 100.
The results suggested that vegetarians overall had a lower likelihood of reaching age 100 compared with omnivores. According to the study, vegetarians had about a 19 percent lower likelihood of becoming centenarians than meat eaters. Vegans showed an even lower likelihood. However, people who ate fish, dairy, or eggs had survival odds closer to those of meat eaters.
Yet researchers stressed that these results come with major limitations and should not be interpreted too broadly.
The Catch: Weight and Nutrition Matter
The biggest twist in the findings is that the association was mostly found among underweight older adults.
Researchers discovered that strict vegetarians who were underweight were less likely to live to 100 than meat eaters. In fact, among underweight participants, “daily consumption of meat was associated with a 44 percent higher likelihood of reaching 100 years old” compared with vegetarian diets. But among participants of normal or higher body weight, that relationship disappeared.
This matters because people in advanced age often struggle with declining appetite, muscle loss, weaker bones, and weight loss. Nutrition experts say that once someone reaches their 80s and 90s, the dietary priorities can shift. Instead of mainly preventing chronic disease decades into the future, the focus may become preserving muscle mass, preventing frailty, and ensuring that every meal contains enough calories and nutrients.
Protein becomes especially important in very old age. Some evidence suggests older adults may actually require more dietary protein than current guidelines recommend to help maintain strength and independence. Researchers said foods such as meat, fish, eggs, and dairy can provide high-quality protein along with nutrients like vitamin B12, calcium, and vitamin D that support muscle and bone health.
Men and Women Did Not Show the Same Pattern
One especially interesting result involved differences between men and women.
When researchers separated the data by sex, female meat eaters appeared more likely to reach age 100 than female vegetarians. However, no statistically significant relationship between vegetarian diets and longevity was found among men. In other words, the apparent benefit linked to meat consumption appeared in women, not men, when the data were analyzed separately.
Researchers did not claim to know exactly why this difference exists. It may relate to differences in body composition, nutritional needs, body weight, or other lifestyle factors that were not fully measured.
Why Experts Are Warning People Not to Overreact
Despite headlines suggesting meat eaters are more likely to live to 100, scientists caution that this study does not prove meat causes longevity.
The research was observational, meaning it only identified associations. It cannot prove cause and effect. Other factors may have influenced the results, including health status, lifestyle habits, or socioeconomic conditions. Researchers also only measured eating habits later in life, meaning they could not track dietary patterns across decades. Some older adults may have changed diets due to illness, chewing difficulties, or appetite changes.
The findings also fit into what researchers call the “obesity paradox,” an observation that slightly higher body weight in older adults sometimes appears linked to better survival, even though excess weight is usually harmful in younger populations. Since underweight participants were most affected in this study, body weight may explain much of the apparent longevity advantage.
Importantly, the study does not erase decades of evidence supporting plant-based eating. Vegetarian and low-meat diets remain linked to lower risks of heart disease, stroke, diabetes, and obesity. Researchers simply argue that nutritional needs change with age and that strict diets in advanced old age may require careful planning.
As the study authors concluded, “Our findings emphasized the importance of a balanced diet from both animal- and plant-derived food for healthy longevity.” Their larger point was not that everyone should eat more meat, but that people in their 80s and 90s may need enough calories, protein, and nutrients to avoid frailty and maintain muscle as they age.
