Do you live longer on a vegetarian or plant-based diet?
A high-quality plant-based diet is associated with less premature death. However, eating strictly vegetarian or vegan has not been proven to be better than a varied diet that occasionally includes meat or fish.
A healthy plant-based eating pattern is associated with a lower risk of premature death. Older Chinese adults who ate the most fresh plant-based foods -- think fruit, vegetables, legumes, nuts and tea -- had a 19% lower chance of dying than those who ate the least of these foods1. Vegetarians also show a lower risk of death from cardiovascular disease across multiple studies, probably due to lower cholesterol, a healthier weight and higher antioxidant intake2,3.
Yet the picture is more nuanced than 'plant-based always wins'. When vegetarians are compared with health-conscious non-vegetarians who occasionally eat meat, the difference in mortality from most cancers and stroke disappears2. A healthy lifestyle in general therefore carries more weight than simply cutting out meat. A recent review study also finds no clear advantage of a fully vegetarian diet over a flexitarian one. Of the well-known regions famous for an exceptionally high number of centenarians, only one has a population that eats predominantly vegetarian4.
The quality of your plant-based food turns out to be decisive, not simply the quantity. A plant-based diet high in preserved vegetables and sugar was actually associated with 17% higher mortality1. Fresh and unprocessed protects; processed and sweetened does not. This distinction matters more than the label 'vegetarian'.
In vegans, the overall mortality rate in available studies is comparable to that of vegetarians and of people who eat meat occasionally5. Among adults over eighty in China, a vegetarian or vegan diet was actually associated with a lower chance of reaching one hundred years of age, particularly in people who were underweight6. At an advanced age, a varied diet containing both animal and plant-based foods appears to be better for an exceptionally long life.
For certain groups, a strictly vegan diet carries concrete risks. Deficiencies in vitamin B12, vitamin D, omega-3 fatty acids, iron, calcium and zinc have been reported in children, pregnant women and older adults5,6,3. Supplements are essential for these groups. That is not a reason to avoid plant-based eating, but it is a reason to pay close attention to it.
All studies are observational, meaning they reveal associations but cannot prove cause and effect. The populations studied vary considerably: China, Europe and North America. Randomised trials with mortality as an endpoint do not exist.
Do you live longer by following the Mediterranean diet?
In large population studies, the Mediterranean diet is consistently associated with lower mortality and less cardiovascular disease; those who want to follow the diet as a whole have the strongest evidence on their side.
Does eating less help you live longer?
In laboratory animals the effect on lifespan is well established, but in healthy humans direct evidence is lacking. A moderate and sustainable eating pattern is wiser than extreme restriction; discuss major changes to your diet with a dietitian or doctor.
Do you actually live longer if you structurally eat fewer calories?
In laboratory animals, eating less convincingly extends lifespan, but this has not yet been demonstrated for healthy people without excess weight. If you want to benefit from what has been shown, eating moderately less or following an interrupted eating pattern are the safest, most reasonably supported options.
Is a low-carbohydrate or ketogenic diet good for longevity?
A ketogenic diet can help with weight problems and metabolic disorders, but for people who simply want to live longer and healthier, no proven advantages over a varied diet have been demonstrated. Those who exercise intensively may even be at a disadvantage.
Is eating organic really healthier?
Eating organic probably does not give you better nutritional value, but it does lower your exposure to pesticide residues and to antibiotic-resistant bacteria through meat. For pregnant women and young children, that is the strongest concrete argument.
Which diet is best supported by evidence for a long, healthy life?
For anyone looking to use diet to invest in a long and healthy life, the Mediterranean diet is currently the best-supported choice. Large human studies consistently show positive effects on both cardiovascular health and cognitive health.