Research reveals meat eaters more often reach 100 – but only if one key condition is met
Interest in living longer and healthier lives has led to research into how diet relates to longevity among the very old. The Chinese Longitudinal Healthy Longevity Survey provides findings from almost two decades of follow-up in more than 5,000 Chinese participants aged 80 and above. The study examined which dietary factors were associated with reaching 100 years.
Where the study was done and what people ate
The study, carried out in China, divided participants into eating-pattern groups: omnivores, vegetarians who still ate fish, eggs or dairy, and strictly plant-based individuals. Omnivores were used as the reference group. Dietary information came from a single self-reported survey, giving a snapshot of participants’ eating habits rather than a record over time.
The results showed that a broadly defined vegetarian diet (without specifying which animal products were excluded) was associated with about a 19% lower probability of reaching 100, with an odds ratio of roughly 0.81 versus omnivores. For those on a strictly plant-based diet the association was stronger, about 29% less likely to reach 100, with an odds ratio of around 0.71. These negative associations did not appear for vegetarians who regularly ate fish, eggs or dairy.
What the results mean, limits and dietary advice
These are observational findings, so they indicate associations rather than proving cause and effect. Several factors could be involved: energy and protein intake, micronutrient levels (particularly vitamin B12, calcium and vitamin D), muscle mass, past illnesses and socioeconomic status. Using a single dietary measure cannot capture changes over time, which limits how far these findings can be generalised beyond this Chinese cohort.
Energy and protein intake are likely important in very old age, especially for people with a BMI under 18.5 (considered underweight), since underweight individuals often experience muscle loss (sarcopenia). Sarcopenia raises the risk of falls, fractures and hospital stays, suggesting that physical condition rather than dietary ideology is most relevant for quality of life in advanced years. Among frail older adults, being a little heavier often links to better survival.
It is also important to identify nutrient shortfalls in strictly plant-based diets. Common gaps include complete proteins, vitamin B12, calcium, vitamin D and the amino acid leucine. Professional societies recommend that from age 70 protein needs rise to 1.0 to 1.2 grams per kilogram of body weight per day, increasing to 1.2 to 1.5 grams during illness or rehabilitation, with each meal targeting 25 to 30 grams of protein.
Practical diet tips
To meet those needs, suggested meals include yoghurt or quark with nuts and oats for breakfast, legumes or lean meat for lunch, and omelettes or lentil soup for dinner. Snacks such as cheese cubes, eggs and edamame can boost energy density. For people who do not eat meat, adding legumes, soy products, fish, eggs and dairy helps fill nutritional gaps, and vitamin B12 supplements are particularly advised for strictly plant-based diets.
Exercise is relevant too, with light resistance training two to three times a week recommended. Testing vitamin D and B12 levels, especially for those with limited sun exposure, is important to avoid deficiencies.
The findings support the importance of maintaining a balance of key nutrients and staying physically active for longevity and quality of life in later years. Because individual needs vary, personalised nutrition and healthcare advice remain important for optimising health in very old age.