Copyright San Diego Union-Tribune
Sixteen years ago, food scientists in Brazil created a new system called Nova, which grouped foods into four ascending health categories based on processing. At the time, the scientists noted that the rising rate of obesity seemed correlated to the growing consumption of highly processed foods. Foods like milk, meats, fruits and vegetables, which undergo little or no processing, were categorized as healthiest (Group 1) while “ultra-processed foods” that combine multiple ingredients, plus additives like high-fructose corn syrup, modified proteins and artificial sweeteners, were mostly junk food (Group 4). Ever since, Nova has guided consumers and food health policies around the world. No one these days argues a potato chip is healthier than a plain baked potato. Ultraprocessed foods are indisputably deemed unhealthy, and frequently linked to increased risk of chronic disease, poor mental health and death. And yet, we can’t seem to get our fill of flavor enhancers, emulsifiers, stabilizers and artificial pigments and sweeteners. Ultra-processed foods now account for more than half of all calories consumed by Americans at home. The numbers are similar around the world. Our waistlines grow with consumption and vice versa. But questions and concerns about Nova persist because the system is based entirely upon the single metric: To what degree is a food altered before consumption? Less is more; more is worse. Or not. In a recent essay in The New England Journal of Medicine, David Ludwig, an endocrinologist and professor of pediatrics at Harvard, underscored these points. Steak, soybeans, olives and peanuts all qualify as members of healthy Group 1 foods, according to Nova criteria, but the nutritional benefits of ground beef, tofu, olive oil and peanut butter (all ultra-processed cousins condemned to Group 4) are not substantially different. To be sure, many additives to ultra-processed foods are demonstrably health-negative. Emulsifiers that make foods like commercial mayonnaise and ice cream possible can disrupt gut mucosa and nitrite-based preservatives in meats like bacon and hot dogs are associated with gastrointestinal cancer. Synthetic food dyes present a rainbow of potential health risks and zero health benefits. But some processing additives like carbonation, lactic acid and various forms of dietary fiber are either innocuous or beneficial to health. Nonetheless, they are considered unhealthy by the Nova system. With good intent if not always good data, some health policy and nutrition advocates urge wholesale reform of the nation’s — and world’s — food systems, based on Nova. In their view, ultraprocessed foods can and should be avoided at all cost. Or the cost will be our health and lives. But it’s not that simple. Most junk food is junk. Pop Tarts, curly fries, chicken tenders, corn dogs, cinnamon rolls and Frappuccinos are tasty invitations to overdose on sugars, fats and salt. But other Group 4 ultra-processed foods offer proven health benefits, such as dark chocolate and plant-based meat substitutes. The fact is relatively little science has been conducted to substantially address and assess the real and long-term health effects of ultra-processed foods. Or what it would mean to eliminate them altogether, especially in population groups with limited access or ability to buy more expensive, less processed foods. Our bodies are complicated machines. What we put into them is complicated too, not only by how food is processed but more fundamentally in terms of nutritional value and safety. Like other pressing health issues today, it is not wise to act rashly, driven only by misguided, ill-informed or empirically baseless notions and agendas. There is much we can do to improve what we eat. That’s food for thought — and science. Brenner is a physician-scientist and president and chief executive of the Sanford Burnham Prebys medical research institute in La Jolla.
