You can't always assume plant-based foods are good for your health. Many snack foods — think potato chips — are plant-based, and if the plant-based food is manufactured and ultra-processed, rather than adding to your health, a recent British study found, they will raise your risk for heart attack and stroke.

On the other hand, those plant foods that remain closest to their natural form and are just cleaned, cut and packaged do help to lower your risk of cardiovascular diseases. These foods include whole grains, fruits and nuts and contain fiber and a wide range of compounds that reduce inflammation and promote overall health.

Eat a diet of mostly minimally-processed foods and avoid foods that come in packages with long lists of colorants, sweeteners, flavor enhancers, emulsifiers and other additives that you would not use in your home kitchen.

The new study looked at the health and lifestyle habits of 118,000 adults from England, Scotland and Wales, who were tracked for around a decade as part of the UK Biobank. The participants responded to questions about their diets, habits and environments on several different occasions and also provided biological samples such as blood and urine samples, and their health and medical records.

Here's what the researchers reported:

  • The more ultra-processed foods people consumed, the higher their likelihood of dying of heart disease.
  • Every 10 percent increase in calories from plant-derived ultra-processed foods was associated with a 5 percent higher likelihood of developing cardiovascular disease and a 6 percent higher risk of coronary heart disease in particular.
  • For every 10 percent increase in the consumption of whole plant-based foods that were not ultra-processed — the participants had an 8 percent reduction in their likelihood of developing coronary heart disease and a 20 percent reduction in their risk of dying of it. They also had a 13 percent lower risk of dying of any cardiovascular diseases.
  • Fake meat made up 0.5 percent of all ultra-processed foods consumed by the participants.

Are you convinced and ready to give up on plant-based junk foods? It may not be so easy to do. Ultra-processed foods, whether they involve a plant-based food diet or a carnivore diet, are what scientists have labeled “hyper-palatable,” meaning once you get a taste for manufactured foods, they're hard to resist.

“The artificial and heightened flavors of these foods can lead people to become addicted to these flavors, making it difficult for them to appreciate the natural flavors of real foods such as fruits and vegetables,” lead author, Fernanda Rauber, a researcher at the Center for Epidemiological Research in Nutrition and Health at the University of Sao Paulo in Brazil, said in a press release. So, what are the most common ultra-processed plant-based foods you should avoid?

  • Pastries, buns, biscuits, cakes, packaged breads, cereals, chips and salty snacks
  • Certain candies and soft drinks made from beet, cane and other sugars
  • Sauces, dressings, juices, frozen pizza
  • Meat substitutes including imitation burgers and sausages

Rauber recommends eating a diet of mostly minimally-processed foods and avoiding things that come in packages with long lists of colorants, sweeteners, flavor enhancers, emulsifiers and other additives that you would not use in your home kitchen.

Make natural plant-based foods your first choice. “When you buy ready-made food or preparations, the best tip is to read the ingredient list,” said Rauber. “If it contains only ingredients that you recognize and commonly have in your kitchen it is more likely made from real food and is not an ultra-processed food.”

The study is published in The Lancet Regional Health-Europe.