U.S. study: Ultra-processed foods threaten brain health
Ultra-processed foods — industrial cookies, sodas, ready-made meals, sugary cereals, and salty snacks — have become a defining feature of modern diets. Convenient, affordable, and widely available, they now make up a growing share of daily calorie intake. Yet a recent American study conducted by researchers at Boston University and published in JAMA Neurology warns that excessive consumption of such foods may be linked to premature cognitive decline and an increased risk of dementia.
According to the study, individuals who get more than 20% of their daily calories from ultra-processed foods are significantly more likely to experience cognitive impairments such as memory loss, reduced focus, and slower learning. The research team followed more than 10,000 participants over a decade, monitoring their eating habits, lifestyles, and brain health. Those who consumed the most processed foods experienced cognitive decline up to 28% faster than those who maintained a balanced, natural diet.
Ultra-processed foods are characterized by their industrial composition — high amounts of added sugars, saturated fats, salt, and various chemical additives designed to enhance flavor, texture, and shelf life. These components trigger chronic inflammation throughout the body, including the brain. Neuroinflammation is now recognized as one of the key factors contributing to neuronal damage and the onset of neurodegenerative diseases such as Alzheimer’s and vascular dementia.
The study also revealed a decrease in the volume of certain brain regions, particularly the hippocampus — a structure crucial for memory and learning — among heavy consumers of ultra-processed foods. Researchers suggest that chemical additives and hydrogenated fats can disrupt neuronal communication, while frequent blood sugar spikes induce oxidative stress that damages brain cells.
Lead researcher Dr. Mark Peterson explained that “the human brain depends on a delicate metabolic balance, and any diet that disrupts this equilibrium — by overloading the body with industrial sugars and fats — can have long-term effects on its function.” He emphasized that the risk is cumulative rather than immediate, developing gradually with years of exposure.
These findings reinforce previous studies from Brazil, France, and the United Kingdom, which have linked high consumption of ultra-processed foods to metabolic disorders and mental decline. A French NutriNet-Santé study, for example, showed that a 10% increase in the proportion of ultra-processed foods in the diet was associated with a 14% rise in overall mortality risk.
Nutrition experts therefore recommend prioritizing unprocessed, whole foods such as fruits, vegetables, whole grains, legumes, nuts, and fatty fish rich in omega-3 fatty acids. Omega-3s, in particular, play a crucial role in maintaining neuronal integrity and protecting against cognitive aging.
Public health specialists stress that the issue is not purely individual but societal. In many modern contexts, ultra-processed foods serve as a response to economic and social pressures: limited time, higher prices of fresh produce, aggressive marketing, and lack of nutritional education. U.S. health authorities are urging stronger policies to regulate food advertising, improve labeling transparency, and make healthy options more affordable.
In essence, this research underscores a vital truth: our brain is as vulnerable as our heart to poor dietary habits. Reducing the share of ultra-processed foods — even gradually — is one of the simplest yet most effective ways to preserve both physical and mental health. In a world driven by convenience, rediscovering the value of authentic, minimally processed foods may be the key to maintaining clarity, memory, and vitality throughout life.
