Lifestyle Changes Can Slow Cognitive Decline

Intensive lifestyle changes — eating minimally processed plant-based foods plus frequent exercise, stress reduction and support groups — may reduce the symptoms of mild cognitive impairment and early Alzheimer’s disease, according to a newly released study.

“This is important because most people diagnosed are told it can only get worse,” says Dean Ornish, M.D., the well-known lifestyle medicine advocate who directed the randomized controlled clinical trial, regarded as the gold standard in human research. “It’s a devastating diagnosis. When you lose your memories, you lose everything. You lose hope. These findings may give many people new hope and new choices they didn’t have before.”

The Alzheimer’s disease burden already is large and expected to grow in the coming years. In 2023, as many as 6.7 million Americans were living with Alzheimer’s disease. This number is predicted to reach nearly 14 million by 2060, according to the Centers for Disease Control and Prevention.

Previous studies have suggested that healthy habits contribute to preventing dementia, including research that advocates the Mediterranean diet, an eating plan that emphasizes healthy fats, whole grains, fruits, vegetables, seeds and nuts. But this study is believed to be the first to demonstrate improvements among people already diagnosed with the condition.

The peer-reviewed study, published June 6 in the journal Alzheimer’s Research and Therapy, was led by Ornish, founder and president of the Preventive Medicine Research Institute and clinical professor of medicine at the University of California, San Francisco, in collaboration with leading scientists and neurologists from several other academic medical centers, among them, Harvard Medical School, Duke University and the University of California, San Diego.

The study enlisted 51 participants and divided them into two groups, one that adopted the drug-free lifestyle intervention program for 20 weeks, and a second comparison group that followed their usual habits and treatments, including medications they might be taking. Two dropped out and were excluded from the analyses.

The program required commitment. The diet is vegan: a minimally processed plant-based diet low in saturated fats, refined carbohydrates, alcohol and sweeteners, with mostly fruits, vegetables, whole grains and legumes, plus selected supplements, including a multivitamin; moderate aerobic exercise and strength training for at least 30 minutes a day; stress management with meditation, stretching, breathing and imagery, for one hour a day; and one-hour support groups for patients and their spouses or study partners, three times per week. All the meals were sent to patients’ homes to encourage compliance.

At the end of the study period, the researchers found “statistically significant” differences between the two groups as measured by four standard tests that assess cognition. The majority — but not all — of the intervention patients showed improvements, while the control group did not.