An artist's rendering of plant-based burgers in a food processing plant. (Image credit: guteksk7 via Getty Images)
Recent publications have criticized plant-based meat substitutes—such as veggie hot dogs and textured vegetable protein—as unhealthy, and have claimed that their consumption is associated with increased risk of heart disease and mortality. However, a deeper look at the research on which these claims are based reveals a more complex picture.
In fact, the real culprits are “plant-based” ultra-processed foods in general, not meat substitutes specifically, according to the paper that made the headlines. It’s worth noting, however, that “plant-based” foods include those that might surprise you, like chocolate chip cookies, frozen pizza, and fizzy drinks. A study published earlier this month in the Lancet Regional Health–Europe linked plant-based ultra-processed foods to an increased risk of heart disease and death.
However, plant-based meats accounted for only a small proportion of the study participants’ overall food intake, and it was not designed to pinpoint which foods had the most significant links to negative health outcomes. Still, the mixed interpretations highlight how complex nutrition research can be, critics say, since the definitions of foods used by scientists don’t always reflect what others might perceive as a plant-based diet.
Foods are described as ultra-processed when they undergo an industrial transformation that significantly alters their original ingredients. These products go through a long journey before they end up on your table. Staples like instant noodles and store-bought cookies typically go through multiple processing steps that expose the internal structure of their raw components. They’re then reassembled in a form that emphasizes convenience and taste — often with additives designed to improve presentation and shelf life. The rule of thumb is to “think about foods you couldn’t make in your own kitchen” because of their chemical ingredients or the industrial equipment needed to prepare them, says Evangeline Mantzioris, a researcher and nutritionist at the University of South Australia who was not involved in the study.
Nutrition studies, including this widely discussed paper, use the NOVA classification system as a guide to group foods along a spectrum from unprocessed to ultra-processed based on the degree to which they are altered from their natural state. Most foods can be categorized intuitively. For example, broccoli or beans are not considered ultra-processed, while breakfast cereals and canned soups are. However, some examples may not be obvious at first glance. For example, a new Lancet Regional Health–Europe study listed beer and wine as examples of non-ultra-processed beverages, while spirits like vodka were considered ultra-processed.
The key idea behind applying this framework to food research is that processing food can radically change how it interacts with the body, which can impact health, says Fernanda Rauber, lead author of the new study and a nutritional epidemiologist at the University of Sao Paulo in Brazil. The impact of food on health is not limited to “just the sum of its nutritional functions,” she says. “The way foods are combined, prepared, and consumed as meals also plays a key role in their impact on health.”
Sourse: www.livescience.com
