A newly published, long-running study calls into question the validity of the link between a healthy diet and lowered risk of dementia.
The study, published earlier this month in the Journal of the American Medical Association, followed more than 8,200 London-based middle-aged adults for 25 years. Over the course of the study, 344 of the participants were diagnosed with Alzheimer’s. Rates of diagnosis were found to be similar for the one-third of participants consuming a diet rich in fruits, vegetables, nuts, legumes, and unsaturated fats and low in meat, sodium, and sugary drinks as for the remaining participants.
But experts warn against drawing conclusions based in false causality from this observational study.
"Not evidencing an association between midlife diet and dementia does not mean that diet does not matter on cognitive health," study author Tasnime Akbaraly, a researcher at Inserm, the French National Institute of Health and Medical Research at the University of Montpellier, tells CNN.
She also notes that the study found a "slight decrease in diet quality in the years preceding dementia diagnosis [which] suggests that unhealthy diet could be part of the cascade of changes occurring in the preclinical phase of dementia."
Previous studies have indicated that a healthy diet can, in fact, prevent or slow the development of dementia. One 2018 study found a link between a Mediterranean diet rich in fish, olive oil, fruits, and vegetables and slowed development of the disease, and Alzheimer’s nonprofits around the world, including the British Alzheimer’s Society and the American Alzheimer’s Association, recommend a Mediterranean diet as a way to reduce risk factors for Alzheimer’s. Alzheimer's is the most common form of dementia, accounting for somewhere between 60 and 80 percent of cases.
The Alzheimer's Association is currently sponsoring a trial on the effects of diet, exercise, and mentally stimulating activities on the risk of dementia.
Previous studies have shown that an unhealthy diet can contribute to increased risk of metabolic disease, diabetes, and Alzheimer’s. Others have shown a link between the consumption of animal proteins and increased risk of developing the disease.
Related on Organic Authority
One of the Most Important Steps You Can Take to Preventing Alzheimer's Disease
Decreased Alzheimer's Risk and Healthy Weight Linked to Olive Oil Consumption
Certain Types of Anti-Anxiety Medication Could Raise Your Risk of Alzheimer's