According to a new study, eating a nutritious plant-based diet is linked to a lower risk of diabetes
The European Association for the Study of Diabetes (EASD) journal Diabetologia published new research that found that people who eat healthy plant-based foods like fruits, vegetables, nuts, coffee, and legumes have a lower risk of developing type 2 diabetes (T2D). People who eat healthy plant-based foods have a lower risk of developing T2D.
The study, which aimed to identify metabolite profiles associated with various plant-based diets and investigate possible associations between those profiles and the risk of developing T2D, was conducted by Professor Frank Hu and colleagues from the Harvard T.H. Chan School of Public Health’s Department of Nutrition in Boston, Massachusetts.
All the large numbers of substances found in various diets, as well as the complex diversity of molecules made as those compounds are broken down and converted for use by the body, are metabolites. Because foods have different chemical compositions, an individual’s metabolite profile should mirror their diet.
Recent improvements in high-throughput metabolomics profiling have ushered in a new era of nutritional study. The full examination and identification of all the various metabolites contained inside a biological sample is referred to as “metabolomics.”
Type 2 diabetes accounts for over 90% of all diabetes cases, and it is a huge health threat all over the world. In less than two decades, the number of people who have the disease has more than quadrupled around the world. In 2000, there were about 150 million people who had the disease, but by 2019, there were more than 450 million people who had it, with a projected rise to 700 million people by 2045.
T2D’s worldwide health impact is exacerbated by the disease’s various consequences, both macrovascular (such as cardiovascular disease) and microvascular, which affect the kidneys, eyes, and neurological system.
Unhealthy diets, being overweight or obese, genetic susceptibility, and other lifestyle factors such as a lack of exercise are the primary causes of diabetes. Plant-based diets, particularly those that are high in high-quality foods such as whole grains, fruits, and vegetables, have been linked to a lower incidence of T2D, although the underlying mechanisms are yet unknown.
Blood plasma samples and food consumption of 10,684 people from three prospective cohorts (Nurses’ Health Study, Nurses’ Health Study II, and Health Professionals Follow-up Study) were analyzed by the researchers. The majority of the participants were white, middle-aged (mean age, 54 years), and had a BMI of 25.6 kg/m2.
Participants in the study completed food frequency questionnaires (FFQs) that were assessed based on their adherence to one of three plant-based diets: an overall Plant-based Diet Index (PDI), a healthy Plant-based Diet Index (hPDI), or an unhealthy Plant-Based Diet Index (UPDI) (uPDI).
Healthy plant foods (whole grains, fruits, vegetables, nuts, legumes, vegetable oils, and tea/coffee); unhealthy plant foods (refined grains, fruit juices, potatoes, sugar-sweetened beverages, and sweets/desserts); and animal foods (animal fats, dairy, eggs, fish/seafood, meat, and miscellaneous animal-based foods) were used to create diet indices.
The researchers divided plant foods into healthy and unhealthy categories based on their links to T2D, cardiovascular disease, some malignancies, and other disorders like obesity and high blood pressure.
The researchers used blood samples taken in the early stages of the three studies listed above to establish metabolite profile scores for the participants, and any incidences of incident T2D were recorded during the study’s follow-up period.
The team was able to uncover any associations between metabolite profiles, diet indexes, and T2D risk by analyzing these data along with the diet index scores.
Participants who were diagnosed with T2D during follow-up had a lower intake of nutritious plant-based foods, as well as lower PDI and hPDI scores, compared to those who did not develop the condition. They were also more likely to have high blood pressure and cholesterol levels, take blood pressure and cholesterol medications, have a family history of diabetes, and be less physically active.
According to the metabolomics data, plant-based diets were linked to distinct multi-metabolite profiles, which differed considerably between healthy and unhealthy plant-based diets.
Furthermore, metabolite profile scores for both the overall plant-based diet and the healthy plant-based diet were inversely associated with incident T2D in a generally healthy population, independent of BMI and other diabetes risk factors, while the unhealthy plant-based diet had no such association.
To show that people were more likely to stick to their diets, their metabolite profile scores for PDI and hPDI were higher.
After controlling for levels of trigonelline, hippurate, isoleucine, a small set of triacyglycerols (TAGs), and numerous other intermediate metabolites, the link between plant-based diets and T2D essentially vanished, implying that they may play a crucial role in linking those diets to incident diabetes.
Trigonelline, for example, is found in coffee and has been shown in animal studies to reduce insulin resistance, while higher levels of hippurate are linked to better glycaemic management, increased insulin secretion, and a lower incidence of T2D.
The researchers think that these metabolites should be looked into more because they could show how plant-based diets can lower the risk of Type 2 diabetes.
While it’s difficult to separate the contributions of individual foods because they were all studied as a pattern, Professor Hu explains that individual metabolites from polyphenol-rich plant foods like fruits, vegetables, coffee, and legumes are all closely linked to a healthy plant-based diet and a lower risk of diabetes.
The authors come to this conclusion: “Our findings back up the importance of eating a healthy plant-based diet in preventing diabetes and offer fresh avenues for further research.”
For the time being, our findings on intermediate metabolites are exciting, but more research is needed to confirm their causative significance in the relationships between plant-based diets and the risk of type 2 diabetes.
It’s not possible to get long-term repeated metabolomics data because they only took blood samples once. This means that they can’t figure out how a person’s diet changes their metabolome, which increases their risk of Type 2 diabetes.