A comprehensive meta-analysis provides comprehensive evidence that consistently following a healthy, plant-based diet could help reduce the risk of type 2 diabete.
More than 100 million adults in the United States have diabetes or prediabetes— the set of conditions that precede the development of type 2 diabetes, according to data from the Centers of Disease Control and Prevention (CDC).
Diet is one of the major risk factors for type 2 diabetes— the most common form of diabetes. However, this is a modifiable entity, meaning that if a person adopts healthier dietary habits, their risk of developing this metabolic condition may be reduced.
Several studies have shown in recent years that vegan, vegetarian, or other plant-based diets can substantially reduce a person’s risk of diabetes.
A team of researchers from the Harvard T. H. Chan Public Health School in Boston, MA, have now completed a systematic study and meta-analysis of nine studies that examined the relationship between dietary habits and type 2 diabetes risk.
These studies involved no fewer than 307,099 people, 23,544 of whom had type 2 diabetes.
“Plant based dietary patterns are gaining popularity in recent years, so we thought it was crucial to quantify their overall association with diabetes risk, particularly since these diets can vary substantially in terms of their food composition,” said by the review’s first author Frank Qian.
Qian and colleagues report their findings in a paper that appeared yesterday in JAMA Internal Medicine.
Adherence and healthiness both matter
In their analysis, Qian and team first examined how adherence to a predominantly plant-based diet of any type associated with the risk of diabetes.
“Predominantly plant-based” in this case may mean a diet that centered on both healthy plant foods, including fruits, vegetables, nuts, and legumes, and less healthy ones, such as potatoes and sugars. Such types of diets might include other items of animal origin as well.
The team then analyzed the link between the risk of diabetes and healthy plant-based diets that mainly contained a high amount of healthy fruit, vegetables, legumes, whole grains, and nuts.
The researchers found that participants who adhered more strictly to plant-based diets generally had a 23 percent lower risk of type 2 diabetes compared to those who adhered less strictly to these dietary patterns.
However, they add that in the case of individuals who adhered to strictly healthy plant-based diets the association with a lower risk of type 2 diabetes was even stronger.
Although the researchers have only established a correlation, they believe it may be underpinned by a causal relation. They also note that there are several mechanisms which could explain this relation.
For one, they note that healthy, plant-based foods can demonstrably improve both insulin sensitivity and blood pressure, with each playing a role in diabetes development. Additionally, plant-based diets can prevent or reduce weight gain, as well as reduce low-grade inflammation, two other factors that contribute to the risk of diabetes in a person.
“Overall, these data highlighted the importance of adhering to plant based diets to achieve or maintain good health, and people should choose fresh fruits and vegetables, whole grains, tofu, and other health[ful] plant foods as the cornerstone of such diets.”.
Senior author Dr. Qi Sun
While current research obtained only grants from national research funding agencies (the National Institutes of Health), some of the writers involved in the study have identified potential conflicts of interest.
Therefore, one co-author reported receiving funding from the California Walnut Commission for individual studies, as well as honoraria from Metagenics and Standard Process, two companies that manufacture dietary supplements. Dr. Sun reported receiving consulting fees from Emavant Solutions GmbH, a company providing healthcare facilities.
