This suggests other characteristics beyond abstinence from meat may contribute to better health among vegetarians. More simply, it’s the associated healthier behaviours that generally come with being a vegetarian – such as not smoking, maintaining a healthy weight, exercising regularly - that explain why vegetarians tend to have better health outcomes than non-vegetarians.
In a separate study we conducted using data from the 45 and Up Study, we found people who ate more fruit and vegetables, particularly those who had seven or more serves per day, had a lower risk of death than those who consumed less, even when other factors were accounted for.
And although there is unclear evidence a vegetarian diet promotes longevity, studies have consistently shown other health benefits. For example, a vegetarian diet has been consistently associated with a reduced risk of high blood pressure, type 2 diabetes and obesity.
A meta-analysis (a statistical analysis that combines data from multiple studies) from 2012 concluded vegetarians had a 29% lower risk of early death from heart disease and an 18% lower risk for cancer.
It’s important to keep in mind that the International Agency for Research on Cancer, the cancer agency of the World Health Organisation, has classified the consumption of processed meat as carcinogenic and red meat as probably carcinogenic to humans.
So what does it all mean?
While we can’t say for certain if being a vegetarian helps you live longer, we do know having a well-planned, balanced diet with sufficient fruit and vegetables is certainly good for you.
We also know sufficient physical activity, moderating alcohol consumption and avoiding tobacco smoking are key factors in living longer. And the growing body of evidence shows vegetarians are more likely to have these healthy habits.