The colorings, additives and preservatives added to food products, as well as food processing techniques, are a source of great concern in 2026 because they are ubiquitous worldwide, yet the effects of these items on metabolic health are not fully understood. In addition, researchers are increasingly investigating how these dietary items may also affect the brain as people age. Dr. Owen Carmichael of LSU’s Pennington Biomedical Research Center is helping advance that understanding through a new comprehensive look at the potential relationship between ultraprocessed foods – those featuring extensive processing and additives – and the aging brain.
Dr. Carmichael , James W. and Neil Ann Parks Professor for Dementia Research, Prevention and Treatment, is the lead author of a new paper published in the Annual Review of Nutrition, “ Ultraprocessed Foods and the Aging Brain: State of the Science ,” that examines the growing body of research on ultraprocessed foods, brain health, cognitive function and dementia. The work brings together findings from human studies and basic research to examine what scientists know about the potential connections – and where important questions remain unanswered.
Ultraprocessed foods make up a significant portion of the modern diet. These foods are generally formulated through industrial processes and often contain combinations of refined ingredients, added sugars, fats, sodium and other additives. Research has increasingly linked higher consumption of ultraprocessed foods with a variety of health outcomes, prompting scientists to ask whether similar relationships may exist with brain health.
The review examines several ways diet could potentially influence the aging brain, including pathways involving metabolism, inflammation, vascular health and other biological processes. It also considers evidence connecting ultraprocessed food consumption with cognitive performance and dementia-related outcomes. But the authors emphasize that association does not necessarily establish cause and effect.
Some studies have found relationships between greater consumption of ultraprocessed foods and poorer cognitive outcomes, but researchers are still working to determine how much of that relationship can be attributed directly to the foods themselves and how much may reflect other characteristics of diet, lifestyle or health.
That distinction is important as scientists work toward a more complete understanding of how nutrition affects the brain.
“A lot of people inside and outside of science are worried about the effects that food processing and artificial food additives might have on health, but it is hard to know what reported health effects are real and which ones are not. This review gives us an opportunity to step back and look at all the evidence we know of that suggests that ultraprocessed foods could affect the brain,” Dr. Carmichael said. “The bottom line is that some of the data is concerning, but there are still many unanswered questions about how these relationships work and what they mean for long-term cognitive health.”
Dr. Carmichael is the Director of Biomedical Imaging at Pennington Biomedical, where he oversees MRI, DXA and ultrasound data collection and analysis. His research focuses on the effects of health behaviors (including dietary choices) and metabolic health on Alzheimer’s disease and brain aging, using advanced biomedical imaging techniques as a tool.
About LSU's Pennington Biomedical Research Center
The Pennington Biomedical Research Center is at the forefront of medical discovery as it relates to understanding the triggers of obesity, diabetes, cardiovascular disease, cancer and dementia. Pennington Biomedical has the vision to lead the world in promoting nutrition and metabolic health and eliminating metabolic disease through scientific discoveries that create solutions from cells to society. The Center conducts basic, clinical and population research, and is a campus in the LSU System.
The research enterprise at Pennington Biomedical includes over 600 employees within a network of 44 clinics and research laboratories, and 16 highly specialized core service facilities. Its scientists and physician-scientists are supported by research trainees, lab technicians, nurses, dietitians and other support personnel. Pennington Biomedical is a globally recognized state-of-the-art research institution in Baton Rouge, Louisiana. For more information, see www.pbrc.edu .
Annual Review of Nutrition
10.1146/annurev-nutr-061824-053453
Commentary/editorial
Ultraprocessed Foods and the Aging Brain: State of the Science
O.T.C. is the chair of the Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment (ISTAART) Nutrition, Metabolism and Dementia professional interest area (PIA) and has a consulting agreement with Clario, Inc. D.M.v.L. is the immediate past chair of the Alzheimer's Association ISTAART Nutrition, Metabolism and Dementia PIA. H.L.S. is a board member for Dementia Alliance International and a member of the Alzheimer's Association ISTAART. The other authors are not aware of any affiliations, memberships, funding, or financial holdings that might be perceived as affecting the objectivity of this review. This manuscript was facilitated by the Alzheimer's Association ISTAART, through the Nutrition, Metabolism, and Dementia PIA and the Neurophysiology PIA. The views and opinions expressed by the authors in this publication represent those of the authors and do not necessarily reflect those of the PIA membership, ISTAART, or the Alzheimer's Association.