High levels of ultra-processed foods linked with early death, brain issues

A large study suggests that there might be a striking reason to limit your intake of ultra-processed foods - early death.

The study of 115,000 people found that those who ate large amounts of ultra-processed foods, especially processed meats, sugary breakfast foods and sugar and artificially sweetened beverages, were more likely to die prematurely.

The research, published Wednesday in the journal BMJ, adds to a growing body of evidence that has linked ultra-processed foods to a higher rate of health problems. Ultra-processed foods encompass a broad category ranging from cookies, doughnuts and potato chips to hot dogs, white bread and frozen meals. Scientists say what these foods have in common is that they are typically formulations of industrial ingredients that are designed by manufacturers to achieve a certain “bliss point,” which causes us to crave and overeat them. They also tend to be low in nutrients such as fiber, vitamins and minerals.

Here are some of the key findings:

- Mortality risk: When the researchers looked at intake of ultra-processed foods, they found that participants who consumed the most - averaging seven servings of these foods per day or more - had a slightly higher risk of dying early compared with people who consumed the least ultra-processed foods.

- Brain health: The study found that people who ate the most ultra-processed foods had an 8% higher likelihood of dying from neurodegenerative diseases such as multiple sclerosis, dementia and Parkinson’s disease. But they did not find a higher risk of deaths from cancer or cardiovascular disease.

- Increased risk with certain foods: The researchers found that there were certain ultra-processed foods that were particularly associated with harm. These included processed meats, white bread, sugary cereals and other highly processed breakfast foods, potato chips, sugary snacks and sugary beverages, and artificially sweetened drinks, such as diet soda.

- Study limitations: The researchers cautioned that their findings were not definitive. The study showed only associations, not cause and effect. People who consume a lot of ultra-processed foods tend to engage in other unhealthy habits. They eat fewer fruits, vegetables and whole grains, are more likely to smoke and less likely to be physically active. The researchers took these factors into account when they did their analysis, but other variables could have played a role as well.

Risk of high ultra-processed diets

In recent years, studies have found that eating a diet high in ultra-processed foods causes people to quickly gain weight and increases their risk of at least 32 different health conditions, including cancer, Type 2 diabetes, heart disease, obesity, anxiety, depression and dementia. A handful of studies have also found that diets high in ultra-processed foods increase the risk of early death. But many of these studies were relatively small, short in duration or did not look into specific causes of death.

The new study addressed these issues by analyzing data on tens of thousands of adults who were followed for more than 30 years, said Mingyang Song, lead author of the study and a professor of clinical epidemiology and nutrition at the Harvard T.H. Chan School of Public Health.

“There has been great interest from both the public and scientific community in understanding the health impact of ultra-processed foods, which now account for more than 60% of daily calories in Americans,” Song said in an email.

The study included two groups, a cohort of about 75,000 registered nurses who were tracked from 1984 to 2018, and a group of roughly 40,000 male doctors and health professionals who were followed from 1986 to 2018. The participants answered questions about their health and lifestyle habits every two years and provided details about the foods they ate every four years.

Previous studies have found that consuming a lot of ultra-processed foods could drive inflammation in the brain and weaken the blood-brain barrier, setting the stage for neurodegeneration. There is also evidence that ultra-processed foods can hamper overall health by reducing insulin sensitivity, disturbing gut microbiota, and driving weight gain and chronic inflammation throughout the body.

Some foods are better than others

The new findings support the idea that all ultra-processed foods are not the same and that some, such as whole-grain bread for example, can even be healthful, according to an editorial that accompanied the study in BMJ. Some countries have implemented public health measures to help people improve their diets, such as banning companies from using trans fats in their products, putting warning labels on sugary junk foods and restricting the marketing of unhealthy foods to children.

The authors of the BMJ editorial, Kathryn E. Bradbury and Sally Mackay, two nutrition experts at the University of Auckland, said these and other public health interventions should be adopted more widely.

“Our global food system is dominated by packaged foods that often have a poor nutritional profile,” they wrote. “This system largely serves the goals of multinational food companies, which formulate food products from cheap raw materials into marketable, palatable, and shelf stable food products for profit.”