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Ultra-processed foods (UPFs) have become a defining feature of modern diets, particularly in the United States, where they account for 57% of energy intake among adults. Characterized by their addictive nature, these products often include ingredients designed to enhance palatability, extend shelf-life and boost profitability. They typically contain additives, stabilizers, colorants, emulsifiers and sweeteners, making them highly irresistible. As UPFs continue to fill grocery aisles and fast-food menus, understanding their impact on health and society is crucial.

What Makes Foods Ultra-Processed?

To better understand food processing, Dr. Monteiro, a nutritional epidemiologist in Brazil, created the Nova food classification system to categorize foods into four distinct groups. The first category includes unprocessed or minimally processed foods, such as fresh or frozen fruits and vegetables, beans, lentils, meats, poultry, yogurt, coffee, various herbs and spices. The second category includes ingredients like cooking oils, butter, sugar, honey, vinegar and salt. Canned, fermented and baked foods like breads, cheeses and canned vegetables make up the third group. Finally, UPFs fall in the fourth category, which are made using high-fructose corn syrup, hydrogenated oils and concentrated proteins like soy isolate. These foods often include additives to enhance flavor and appearance, such as what you would find in sodas, chips, candies and packaged meals. Despite the controversies about the NOVA food classification and the term UPF, we believe it is a useful construct to illustrate the negative health effects of our modern diet.

How Do UPFs Impact Health?

A recent study has shed new light on the relationship between UPF consumption and cardiovascular disease. Participants, primarily health professionals in the US, completed detailed dietary questionnaires starting in the 1980’s and continued every two to four years for nearly 30 years. After adjusting for various risk factors, the researchers found that individuals who consumed the most UPFs were 11% more likely to develop cardiovascular disease and 16% more likely to develop coronary heart disease compared to those who consumed the least. Additionally, the highest consumers revealed a slightly elevated risk of stroke. In a separate analysis, the results were even more pronounced: those consuming the most UPFs were 17% more likely to develop cardiovascular disease and 23% more likely to develop coronary heart disease. While these studies have been considered robust for their dietary checks and large population sizes, they still cannot prove cause and effect. Rather, they reveal that the health risks associated with eating UPFs are mostly related to cardiovascular complications. Not only do UPFs pose a risk to cardiovascular health, but another team of researchers have discovered that certain food additives in UPFs can change the gut microbiota composition and may cause low grade immune activation in the gut. Therefore, UPF consumption should be limited to avoid adverse effects on cardiovascular and gut health.

Are Some Ultra-Processed Foods Worse than Others?

Researchers have also identified two categories with particularly strong links to cardiovascular disease risk. They found that sugar-sweetened beverages, such as soda and fruit punch and processed meats including bacon, hot dogs and chicken sausages are most likely to increase the risk for cardiovascular disease. Other UPFs, such as certain breakfast cereals, sweetened yogurts and savory snacks like popcorn were linked to reduced cardiovascular disease risks. Therefore, not all UPFs should be treated equal! Whole grain cereals and breads, despite being ultra processed, provide essential nutrients like fiber and B vitamins, suggesting that the health implications of UPFs mainly depend on their nutritional content and processing methods. For example, processed meats end up being high in sodium and saturated fats. Thus, the difference between the “good guys” and the “bad guys” can be traced back to their ingredients and how they are manufactured.

These studies highlight a few key takeaways: primarily, incorporating more unprocessed or minimally processed foods – such as fruits, vegetables, legumes, nuts and whole grains – into one’s diet is beneficial for health. A diet rich in these foods and low in UPFs correlates with better health outcomes. As the main culprits in UPFs appear to be sodium, saturated fats and sugar, some experts recommend ditching the UPF definition and to emphasize the negative health effects of the main ingredients, e.g. the high amounts of salt, sugar and saturated fats, all of which contribute to the addictive nature of such foods. While being ultra-processed should not be the sole measure of a food’s healthiness, it is crucial to approach all processed foods with awareness and consideration of their harmful ingredients.