by Jed W. Fahey

A common concern of people coming to this country from other parts of the globe is “Why did I start gaining undesired weight when I moved here?” There are certainly many possible answers, but one likely suspect is the ultraprocessed food (UPF) which makes up well over half of the food Americans eat.

Brazilian food scientist Carlos Montiero coined the term “UPF” about 13 years ago as part of an effort to characterize a category dominated by snacks, beverages, ready meals, and other products formulated mostly or entirely from substances extracted or derived from food – or completely synthetic – and including such things as emulsifiers, artificial sweeteners, anti-foaming agents, preservatives, thickeners, bulking, carbonating, gelling, glazing agents, flavors, and coloring agents.

The so-called “standard American diet” of our times is made largely of UPFs that are hazardous to human health. For people who ate healthy meals back home that were based on fresh, local products, navigating the ultraprocessed food supply in the U.S. can be extraordinarily difficult, and presents a true culture shock.   

Ultraprocessed food isthe product of large-scale food manufacturing and has only come into existence within the past two or three generations. A mountain of evidence now shows that UPF is making people sick, facilitating unhealthy weight gain, and shortening lives. Many people also believe UPF makes people less joyful than if they were eating fresh, natural, whole, or minimally processed food.

The UPF category of foods are nutritionally unbalanced, and because they are easy to prepare – or don’t need any preparation at all – as well as to over-consume, they displace other more nutritionally useful foods. UPF is also highly profitable for their manufacturers, due to their long shelf life and the low cost of their ingredients. They are so aggressively marketed by big food companies that about 60% of the total dietary energy intake consumed in countries like the U.S. is now supplied by UPF. Some of the most recent data indicates that 67% of calories in the diets of young people came from UPF and only 23.5% of their diets came from unprocessed foods.

What are some of the pros and cons of UPFs?

Pros: They’re a cheap source of calories. Relative to fresh food, they are inexpensive, and they have great shelf-life (they can last for years in many cases). 

Cons: They are typically loaded with sugar and salt. They contain unnatural ingredients that your body, your mind, and your metabolism never evolved to cope with. Thus, consuming a high-UPC diet can lead to rapid weight gain, addiction to their tastes (e.g. various chips and sweets) without ever being truly satisfied, and toxicity to both your body and your gut microbiome – the trillions of bacteria in your intestines that are working 24/7 to support your digestive, immune, and even your nervous and sensory systems. The calories delivered by UPFs are empty calories. They are stripped of vitamins and minerals and of phytochemicals (the things in plants that give them flavor, smell, and color, and help the human body in a myriad of ways).

Abundant scientific evidence now links consumption of UPF to an increased risk of many chronic diseases, including heart disease, clogged arteries, autoimmune diseases, obesity, cancer, type 2 diabetes, Alzheimer’s, autism, and Parkinson’s. The human race never evolved with these artificial ingredients. They cause unwanted changes in your all-important gut microbiome (the bacteria in your gastrointestinal tract), and in the cells of your body. These changes lead to inflammation, sometimes visible and sometimes invisible. 

Companies add the compounds to help achieve a particular product look, feel, and price – not to make you healthier, but to seduce consumers and make a ton of money for the companies that manufacture them without regard to their nutritional value or long-term health effects. 

Next month: How can we stay healthy?

Dr. Fahey is a nutritional biochemist with faculty appointments at Johns Hopkins University School of Medicine and the University of Maine, Institute of Medicine.