Think Twice About Plant-Based Foods: Some Types Could Heighten Cardiovascular Risks and Mortality

Not all plant-based foods are created equal. A study exposes the risks of the ultra-processed plant-based foods flooding the market.

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Recent research has found that not all plant-based foods are healthy. Ultra-processed foods, even those made from plant-based ingredients, can be detrimental to health and increase the risk of cardiovascular disease (CVD) and mortality.

Previous studies have shown that plant-based foods can lower cholesterol and blood pressure, manage weight, reduce the risk of CVD and diabetes, and decrease the mortality risk from ischemic heart disease.

A plant-based diet encourages the consumption of plant foods and is characterized by minimal or no intake of meat, fish, eggs, or dairy products. However, as ultra-processed foods become more ubiquitous, so do ultra-processed plant-based foods. These include items such as vegan sausages, nuggets, and burgers, as well as plant-based beverages such as soy and plant milks and sugary drinks. Snacks and candies made from processed plant ingredients are increasingly prevalent.

Since the COVID-19 pandemic, more people have started prioritizing their health, leading to a growing consumer interest in plant-based diets. According to data from the Plant Based Foods Association, 70 percent of Americans consumed plant-based foods in 2022, up from 66 percent the previous year. The annual sales of plant-based foods in the United States have also seen significant growth, reaching approximately $8 billion in 2022, a 6.6 percent increase from the previous year. The sales figure increased to $11.51 billion in 2023 and is expected to grow at a compound annual growth rate of nearly 13 percent between 2024 and 2031.

Ultra-Processed Plant-Based Foods Increase Risk of CVD

In June, The Lancet Regional Health–Europe published a study indicating a positive association between the intake of ultra-processed plant-based foods and the risk of CVD and mortality. Conversely, consuming non-ultra-processed plant-based foods was negatively associated with these risks.

The study, which analyzed data from nearly 127,000 individuals aged 40 to 69 in the UK Biobank with a median follow-up of nine years, found that each 10 percent increase in the proportion of total energy intake from ultra-processed plant-based foods was associated with a 5 percent increase in the risk of CVD and a 6 percent increase in the risk of coronary heart disease. The risk of mortality from CVD increased by 12 percent.

The study also indicated that for every 10 percent increase in the proportion of total energy intake from non-ultra-processed plant-based foods, the risk of CVD decreased by 7 percent, and the risk of coronary heart disease decreased by 8 percent. The risk of mortality from CVD decreased by 13 percent, while the risk of mortality from coronary heart disease decreased by 20 percent.

“While ultra-processed foods are often marketed as healthy foods, this large study shows that plant-based ultra-processed foods do not seem to have protective health effects and are linked to poor health outcomes,” Eszter Vamos, co-author of the study and a member of the School of Public Health at Imperial College London, said in a statement.

This is because ultra-processed foods contain not only high levels of salt, fat, and sugar but also various additives.

Fernanda Rauber, the study’s lead author and a researcher at the University of São Paulo in Brazil, said in the statement: “Despite being plant-based, these foods can contribute to risk factors such as dyslipidaemia and hypertension due to their composition and processing methods. Food additives and industrial contaminants present in these foods can cause oxidative stress and inflammation, further aggravating the risks.

“Therefore, our results support the shift towards plant-based food choices that consider the degree of processing to improve cardiovascular health outcomes.”

For the first time, this study provides evidence that the effects of ultra-processed plant-based foods on CVD are significant and should not be overlooked. Therefore, the researchers call for dietary guidelines promoting plant-based diets to focus not only on reducing the intake of animal-sourced foods but also emphasize the importance of limiting the consumption of ultra-processed products.

A previous study from Harvard University and Brigham and Women’s Hospital found that a plant-based diet rich in healthy plant foods can reduce the risk of coronary heart disease, while a diet high in unhealthy plant foods has the opposite effect. However, this study only categorized whole grains, fruits/vegetables, nuts/legumes, plant oils, and tea/coffee as healthy plant-based foods, and juices and sweetened beverages as unhealthy plant-based foods. It did not specifically evaluate the impact of industrial food processing levels.

Higher Consumption of Ultra-Processed Plant-Based Foods Among Vegans

Plant-based foods are generally nutritious and beneficial for health. However, if the degree of processing is overlooked, these foods can become detrimental. Research has found that as industrialized plant-based meat and dairy substitutes become more prevalent, vegetarians may consume more ultra-processed foods than meat-eaters.

A 2021 study published in the Journal of Nutrition indicated that not all vegetarian diets are healthy. Vegetarians who consume excessive amounts of ultra-processed foods, such as plant-based meat and dairy substitutes, may experience the same health issues as meat-eaters.

The study followed more than 20,000 participants with an average age of 56 for five years. Researchers found that among four dietary groups, vegans had the highest intake of ultra-processed foods. The proportion of total energy intake from ultra-processed foods was 33 percent for meat-eaters, almost 33 percent for pesco-vegetarians, 37 percent for vegetarians, and close to 40 percent for vegans.

At the same time, vegetarians had higher unhealthy plant-based diet indices, suggesting that many of them tend to prefer less healthy plant-based products. As a result, their risk of health problems may be comparable to that of nonvegetarians. Vegans and vegetarians with imbalanced diets may face an increased risk of overweight or obesity because of their higher consumption of ultra-processed and unhealthy plant-based foods.

Japanese Diet Reduces CVD Risk and Extends Lifespan

Japan has one of the longest average life expectancies in the world. According to data released by the Japanese government, the average life expectancy for men is 81.5 years and 87.6 years for women. In 2019, approximately 2.06 million people were older than the age of 90. In 2023, The Japan Times reported that the country had surpassed 90,000 centenarians. The longevity of the Japanese population is closely linked to their dietary patterns.

Overall, the Japanese diet is light and nutritionally balanced. Its basic principle is to highlight the ingredients’ natural flavors rather than adding excessive seasonings, and it generally avoids heavy processing. The diet is rich in protein, fiber, vitamins, and minerals and low in saturated fat and sugar. This approach helps provide essential nutrients and maintain a balanced caloric intake, which aids in weight control and reduces the risk of cancer and CVD.

A study published in The BMJ followed nearly 80,000 Japanese people for 10 years and found that those who adhered closely to the Japanese dietary guidelines had a 15 percent lower risk of all-cause mortality.

5 Food Categories of Japanese Diet

1. Grains, such as rice, bread, and noodles
2. Vegetables, such as green vegetables, mushrooms, potatoes, sweet potatoes, yams, and seaweed
3. Fish, meat, and protein, including eggs and organic soy products
4. Dairy, such as milk, butter, and cheese
5. Fruits, such as oranges, apples, persimmons, pears, grapes, and peaches

The food categories are listed in order of the recommended daily servings, totaling 2,000 to 2,400 calories. The guidelines also recommend drinking plenty of water or tea and limiting the consumption of processed snacks, sweets, and sugar-sweetened beverages.