A study suggests that older adults who skip meat may be slightly less likely to live to 100 compared with those who include it in their diet.
But the story is more nuanced than it first appears, and it doesn’t mean plant based diets are bad for everyone.
Researchers tracked over 5,000 adults in China 80 and older through the Chinese Longitudinal Healthy Longevity Survey, which began in 1998.
By 2018, participants who didn’t eat meat were less likely to reach centenarian status than those who ate meat.
Why This Doesn’t Contradict Previous Research
At first glance, these findings seem to conflict with decades of research linking vegetarian and plant based diets to lower risks of heart disease, stroke, type 2 diabetes and obesity.
Those benefits are often tied to higher fiber intake and lower saturated fat consumption.
But it’s important to note who was studied: adults over 80. Older adults have very different nutritional needs than do younger people, and aging changes the body in significant ways.
Energy requirements drop, muscle and bone mass decline, and appetite often decreases.
These changes make malnutrition and frailty more likely.
For younger adults, plant based diets are great for preventing long-term chronic diseases.
For people in advanced age, the priority shifts to maintaining muscle, preventing weight loss in those not overweight, and making sure each meal provides plenty of nutrients.
The study suggests that the lower likelihood of reaching 100 among non-meat eaters may reflect these nutritional challenges rather than a fundamental problem with plant based diets.
Body Weight Plays a Role
The lower likelihood of reaching 100 was seen only in participants who were underweight.
Older adults at a healthy weight didn’t show the same pattern. Being underweight in later life is strongly linked with frailty and higher mortality, which may explain the association.
This aligns with the “obesity paradox” in aging, where a slightly higher body weight is often linked with better survival in later years.
This is often attributed to the misleading nature of BMI numbers between 26 and 29, which is the “overweight” range.
Someone with greater muscle mass will have an elevated BMI, as BMI doesn’t account for body composition.
In fact, if someone has enough muscle but normal amounts of body fat, their BMI can even be in the low “obesity” range.
The effect was also not seen in older adults who included fish, dairy or eggs.
These foods provide high quality protein, vitamin B12, calcium and vitamin D, all essential for preserving muscle and bone health.
Older adults who ate these foods were just as likely to reach 100 as meat eaters.
Healthy Aging
The main message from the study is that dietary needs change with age. Older adults still need sufficient protein, calcium, vitamin D and vitamin B12 to prevent frailty and malnutrition.
Plant based diets can remain healthy, but careful planning or supplementation may be necessary.
What works for a 90-year-old may be very different from what worked at 50.
Adapting your diet as you age is normal and important for long-term health and longevity.
