Meat eaters may look like they have the edge on reaching 100 in a new study, but the story is more complicated than "steak beats salad." The Conversation reports that researchers followed more than 5,000 Chinese adults ages 80 and up as part of the long-running Chinese Longitudinal Healthy Longevity Survey. By 2018, participants who avoided meat were less likely to become centenarians than those who ate it. At first glance, that seems to undercut years of research tying vegetarian and other plant-based diets to lower risks of heart disease, stroke, obesity, and Type 2 diabetes. But those earlier findings largely emerged from younger or middle-aged adults, not people in their 80s and 90s.
In very old age, the body's priorities shift: Energy needs fall, while muscle mass, bone density, and appetite tend to drop, raising the risk of frailty and malnutrition. The key detail in this new study, published in the American Journal of Clinical Nutrition, is that the lower odds of reaching 100 showed up only in underweight nonmeat eaters. Among older adults with a healthy weight, avoiding meat wasn't linked to shorter survival. The pattern also disappeared in people who skipped meat but still ate fish, eggs, or dairy—foods rich in protein, calcium, vitamin D, and vitamin B12, all important for maintaining muscle and bone.
Because this was an observational study, it can't prove that cutting meat causes earlier death; it only shows an association that may be driven by low body weight and undernutrition. And study co-author Kaiyue Wang tells New Scientist that results may not be able to be duplicated in other parts of the world, where diets are different. But the results fit with the so-called "obesity paradox," where a bit of a higher body weight in later life often tracks with better survival, per the Conversation.
Overall, experts say the takeaway isn't that plant-based diets are unhealthy, but that nutrition needs to match age: As people grow older, preventing weight loss and muscle decline can prove important. Plant-based diets can still support healthy aging, they just may require more careful planning—and sometimes supplementation—once you're well past retirement.