Study: Plant-based, highly processed foods lead to heart disease and early death

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Do you want to reduce your risk of chronic diseases, live longer and help the planet at the same time? Experts recommend eating a plant-based diet.

Does this mean you can fill your plate with packaged macaroni and cheese, frozen veggie pizza, or fast food fries and have a donut or two for dessert?

While all of these highly processed foods may be meat-free, they are not without risk, says Duane Mellor, a registered dietitian and senior teaching fellow at Aston Medical School in Birmingham, UK.

“We cannot always assume that plant-based is healthy because, after all, sugar is plant-based,” Mellor said in a statement. “Many foods that do not contain animal products, including biscuits, crisps, candy and soft drinks, are technically plant-based but are not considered an essential part of a healthy diet by the majority of people.”

In fact, eating plant-based junk foods dramatically increases cholesterol and blood pressure and can lead to associated heart disease and early death, according to a new study that the authors call “the first” to show that ultra-processed plant foods are linked to an increased risk of cardiovascular disease.

“Consuming plant-based products can be beneficial and protect against health problems, but it can also pose a risk – it all depends on the level of processing of these foods,” said lead study author Renata Levy, a researcher at the Epidemiological Research Center for Nutrition and Health at the University of São Paulo (Nupens/USP) in Brazil.

Ultra-processed foods undergo numerous industrial processes, such as heating, fracturing of nutrients and proteins, molding and compression, and chemicals are added to cosmetically alter color, smell, taste and texture. Foods in this category are formulated to be particularly palatable to the human palate and are often extremely convenient, requiring little to no preparation time.

Unprocessed foods include fresh fruits and vegetables, eggs, and milk. Minimally processed foods include culinary ingredients such as salt, herbs, and oils, and foods such as canned and frozen vegetables that combine culinary ingredients with unprocessed foods.

“Food additives and industrial contaminants in these foods can cause oxidative stress and inflammation, further exacerbating the risks,” said lead author Fernanda Rauber, a researcher at Nupens/USP.

“Therefore, our results support switching to plant-based foods that take into account the level of processing to improve cardiovascular health,” Rauber said in a statement.

Eat fresh and frozen, minimally processed plants

The study, published on Monday in the journal The Lancet Regional Health – Europe, used data from the UK Biobank, a longitudinal study with participants from England, Scotland and Wales. More than 118,000 people aged between 40 and 69 answered questions about their diet. This information was later linked to hospital and death data on the development of cardiovascular risk factors.

According to the study, highly processed plant-based foods increased the risk of cardiovascular disease by five percent and the risk of early death by 13 percent.

The researchers also found that every 10 percent replacement of highly processed plant foods with fresh, frozen or minimally processed plants reduced the risk of developing cardiovascular disease by 7% while reducing the risk of dying from heart disease by 13%.

The study also looked at plant-based meat products such as sausages, nuggets and burgers, which naturally fall into the category of highly processed foods. However, it is difficult to determine how high the risk of these foods is, said Peter Scarborough, professor of population health at Britain’s University of Oxford, who was not involved in the study.

“Plant-based meat alternatives represent only 0.5% of all highly processed plant-based foods included in this document,” Scarborough said in a statement.

More than half of the highly processed plant foods examined in the study were packaged breads, pastries, rolls, cakes and biscuits.

“It is therefore very difficult to conclude from this paper that plant-based meat alternatives are harmful to health,” Scarborough added.

In addition, much of what is reported in the paper is already known, said Tom Sanders, emeritus professor of nutrition and dietetics at King’s College London, who was not involved in the study.

“It is widely accepted that a balanced plant-based diet, such as the Mediterranean diet or the DASH diet, has a positive impact on cardiovascular health. It is already stressed that unhealthy foods such as chips, etc., sugary drinks, cakes, biscuits and sweets should be avoided,” he said in a statement.

“The latter foods are unhealthy, regardless of whether they are industrially produced or home-made.”

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