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Want to reduce your risk of developing chronic disease, live longer and help the planet at the same time? Experts say a plant-based diet is the way to go.
Does that mean you can load up your plate with boxed mac and cheese, deep-dish frozen veggie pizza, or fast-food fries and have a doughnut or three for dessert?
Duane Mellor, a registered dietitian and senior teaching research fellow at Aston Medical School in Birmingham, UK, said all these ultra-processed foods might be meat-free, but they were not without risks.
“Plant-based foods are not necessarily healthier because sugar comes from plants after all,” Mr Mellor said in a statement. “Many non-animal foods such as biscuits, crisps, confectionery and soft drinks are technically plant-based, but for the majority of people they would not be considered essential to a healthy diet.”
In fact, eating this plant-based junk food could dramatically raise bad cholesterol and high blood pressure, leading to related heart disease and premature death, says the new study, which the authors call “the first study to show that ultra-processed plant foods are associated with an increased risk of cardiovascular disease.”
“Eating plant-based foods can be beneficial, protecting against health problems, or it can pose a risk – it all depends on the level of processing of these foods,” said Renata Levy, a researcher at the Center for Nutrition and Health Epidemiology Research at the University of São Paulo (Nupens/USP) in Brazil and lead author of the study.
Ultra-processed foods undergo multiple industrial processes such as heating, nutrient and protein extraction, molding, compression, and the addition of chemicals that apparently change their color, smell, taste, and texture. Foods in this category are formulated to closely match the human palate and are often very convenient as they require very little time for preparation.
Unprocessed foods include fresh fruits and vegetables, eggs, and milk. Minimally processed foods include cooking ingredients like salt, herbs, and oil, and foods that combine cooking ingredients with unprocessed foods, such as canned or frozen vegetables.
“Food additives and industrial pollutants found in these foods may cause oxidative stress and inflammation, further exacerbating the risk,” said Fernanda Lauber, a research scientist at Nupens/USP and lead author of the study.
“Our findings therefore support a shift towards more processed, plant-based food choices to improve cardiovascular health,” Lauber said in a statement.
Eat fresh or frozen vegetables with minimal processing
The study, published Monday in the journal Lancet Regional Health Europe, drew on data collected from the UK Biobank, a long-term study involving participants from England, Scotland and Wales. More than 118,000 people aged 40 to 69 answered questions about their diet. This information was later linked to hospital and death records for the development of cardiovascular risk factors.
Research has shown that ultra-processed, plant-based foods increase the risk of cardiovascular disease by 5% and premature death by 13%.
The researchers also found that for every 10% replacement of ultra-processed plant-based foods with fresh, frozen, or minimally processed plants, there was a 7% lower risk of developing cardiovascular disease and a 13% lower risk of dying from heart disease.
The study also looked at plant-based meat products, such as sausages, nuggets and burgers, which by their nature are classified as ultra-processed foods, but it's hard to gauge how much risk these foods pose, said Peter Scarborough, a professor of population health at the University of Oxford in the UK, who was not involved in the study.
“Plant-based meat alternatives account for just 0.5% of all ultra-processed plant-based foods included in this paper,” Scarborough said in a statement.
More than half of the ultra-processed plant-based foods studied in the study were packaged breads, pastries, rolls, cakes and cookies.
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Many ultra-processed foods are plant-based, but that doesn't mean they're healthy, experts say.
“So it's very difficult to conclude from this paper that plant-based meat alternatives are unhealthy,” Scarborough added.
What's more, much of what the paper reports was already known, said Tom Sanders, emeritus professor of nutrition at King's College London, who was not involved in the study.
“It's widely accepted that balanced plant-based diets, such as the Mediterranean diet and the DASH diet, are beneficial for cardiovascular health and these diets already emphasize avoiding unhealthy foods such as potato chips, sugary drinks, cakes, biscuits and confectionery,” he said in a statement.
“The latter foods, whether industrially produced or homemade, are unhealthy.”
