Major 20 Year Review Finds Plant-Based Diets Reduce Disease Risk

A major research review has found that eating a plant-based diet improves health and lowers the risk of heart disease and cancer.

The “umbrella review” published in PLOS ONE, assessed 48 other systematic reviews published between January 2000 and June 2023. These reviews analyzed evidence from numerous studies examining the effect of plant-based diets on heart health and cancer risk.

According to the PLOS ONE review, vegetarian and vegan diets are overall “significantly associated” with better health markers. These include lower cholesterol, better regulation of blood sugar levels, healthier body weight, less inflammation, and lower risk of ischemic heart disease and cancer.

Several of the assessed reviews found that vegans had a lower risk of colorectal cancers in particular. This finding will not be news to most, as the increased risk of these cancers from eating meat is well-established. Meanwhile, there were not enough studies to show the risk of death from cancer or cardiometabolic diseases in vegans. But vegetarians were found to have a lower risk of death from cardiovascular diseases.

Vegans and vegetarians generally healthier

group of people in a gym — Jadon Bester/peopleimages.com – stock.adobe.com Plant-based eaters tend to be more physically active than omnivores

The review noted that among the factors that may make vegans and vegetarians healthier is that their lifestyles tend to be healthier overall.

In “the majority of cases,” vegans and vegetarians are more likely to be physical active and consume less sugary drinks, alcohol, and cigarettes. Some of the studies reviewed found that plant-based eaters tend to eat less refined grains and snack foods as well as eating a wider variety of plant foods than omnivores.

Limitations

The researchers warned that there are reasons to view their results with some caution. One is that the studies assessed in the other reviews were not all of the highest research quality. This lowers “the strength of evidence as well as the external validity of the results.”

Secondly, they found there was a lot of diversity in lifestyles, demographics, and sample sizes in the studies reviewed. This means that there could have been many other factors contributing to results that are not accounted for. These include quality of diets and how and when food was prepared and consumed.

However, the researchers state that their “umbrella review seems consistent with other primary evidence that links the consumption of red processed meats to an increased risk of cancers of the gastro-intestinal tract.”