A groundbreaking study has revealed that adopting a healthy plant-based diet could significantly extend the lives of individuals struggling with cardiometabolic diseases such as diabetes, obesity, and heart disease. This study, which analyzed data from nearly 78,000 participants in the U.K., U.S., and China, found compelling evidence that a diet rich in plant-based foods—when carefully selected for their health benefits—could reduce the risk of mortality from various causes, including cardiovascular diseases and cancer.

The study will be presented at the American College of Cardiology’s Annual Scientific Session (ACC.25) in Chicago, Illinois, on March 29, 2025. While the findings are not conclusive proof of cause and effect, they offer encouraging insights for those suffering from chronic health conditions. This is particularly relevant as more people seek dietary changes to manage and prevent long-term health complications.

A Deep Dive Into Healthy and Unhealthy Plant-Based Diets

The research team, led by Dr. Zhangling Chen from the Department of Cardiovascular Medicine at the Second Xiangya Hospital of Central South University, conducted an extensive analysis using data from three major cohort studies. These included:

• 55,000 participants from the U.K. Biobank (2006–2022)
• 18,000 individuals from the U.S. National Health and Nutrition Examination Survey (NHANES) (1999–2018)
• Nearly 4,500 participants from the Chinese Longitudinal Healthy Longevity Study (CLHLS) (2006–2018)

Researchers assessed the participants’ eating habits at the start of each study using 24-hour dietary recalls and questionnaires. Based on this information, they developed two separate indices to score the participants: one for a “healthful” plant-based diet and the other for an “unhealthful” one.

A healthful plant-based diet was defined by high consumption of whole plant foods, including vegetables, fruits, whole grains, legumes, tea, and coffee. In contrast, an unhealthy plant-based diet was characterized by the intake of more processed foods such as refined grains, sugary drinks, and an excess of potatoes and processed plant-based options.

A Significant Impact on Mortality Risk

The results of this research were striking. Those who closely followed a healthful plant-based diet experienced a 17% to 24% reduction in the risk of death from all causes, as well as a decrease in mortality from cardiovascular disease and cancer. On the flip side, those adhering to an unhealthful plant-based diet had a 28% to 36% higher risk of death from these conditions.

Interestingly, this trend held true across different demographic groups, including various age groups, races, and sexes. While the study participants from the U.K. and U.S. were significantly younger—averaging 57 and 59 years old, respectively—compared to the older Chinese cohort (averaging 84 years old), the benefits of a healthy plant-based diet were consistent across countries.

Unraveling the Mechanisms Behind the Benefits

Dr. Thomas M. Holland, a physician-scientist at the RUSH Institute for Healthy Aging in Chicago, who was not involved in the study, explained how plant-based diets influence cardiometabolic health. According to Dr. Holland, a healthy plant-based diet is linked to better control of cholesterol levels, improved blood sugar regulation, reduced inflammation, and better vascular health—all of which contribute to a lower risk of heart disease and cancer.

A healthful plant-based diet, which is rich in vegetables, fruits, whole grains, legumes, and healthy fats like those found in nuts and olive oil, works in several ways:

• It reduces LDL cholesterol and triglycerides while improving HDL cholesterol, ultimately lowering the risk of cardiovascular events such as heart attacks and strokes.
• It enhances insulin sensitivity and helps control blood sugar, benefiting individuals with diabetes.
• It reduces oxidative stress and inflammation, two key drivers of cardiovascular disease and other chronic illnesses.
• It promotes vascular health, which is essential for maintaining a healthy heart and circulatory system.

In contrast, an unhealthy plant-based diet, which may contain high amounts of refined grains, sugar-sweetened beverages, and processed foods, can have detrimental effects. These foods can spike blood sugar, increase inflammation, and impair lipid metabolism, all of which elevate the risk of heart disease, diabetes complications, and even early death.

The Role of Nutrients in Plant-Based Diets

A healthy plant-based diet is not just about avoiding unhealthy foods but also about incorporating nutrient-dense options. Dr. Chen attributes the protective effects of a healthy plant-based diet to the abundant nutrients found in these foods, including dietary fiber, plant-based fats, antioxidants, vitamins, and minerals. These nutrients are associated with a lower risk of cardiometabolic diseases and could help extend life expectancy for individuals with chronic conditions.

For example, fiber from whole grains and legumes helps regulate blood sugar, while healthy fats from plant-based sources such as nuts, avocado, and olive oil can lower LDL cholesterol and promote heart health. The antioxidants found in plant foods, including chlorogenic acids and polyphenols, help reduce systemic inflammation—a major contributor to cardiovascular disease and diabetes progression.

The intake of essential minerals like potassium, magnesium, and calcium, as well as vitamins such as vitamin E and folate, can also significantly improve heart health and reduce the risk of premature death in those with cardiometabolic diseases.

Moving Forward: Tailoring Plant-Based Diets for Diverse Populations

While the study offers promising evidence for the benefits of plant-based diets, further research is necessary to better understand how these diets impact different populations. Dr. Chen mentioned that future investigations could help refine dietary recommendations for people from diverse racial, national, and socioeconomic backgrounds.

“The ultimate goal is to design interventions that are culturally tailored to improve cardiometabolic health and extend life expectancy,” Dr. Chen said. “By understanding how plant-based diets affect different populations, we can make meaningful strides in reducing the global burden of chronic diseases.”

Final Thoughts

For individuals with cardiometabolic conditions such as diabetes, obesity, or heart disease, adopting a healthy plant-based diet could be an effective strategy for improving both health outcomes and longevity. This research highlights that not all plant-based diets are created equal—focusing on whole, minimally processed plant foods while avoiding processed alternatives is key to achieving the most significant benefits. For those looking to improve their health and potentially extend their life expectancy, turning to a healthful plant-based diet may be one of the most impactful changes they can make.