People with early-stage Alzheimer’s disease may be able to slow their cognitive decline through diet and exercise, according to a new study. The study, published in Alzheimer’s Research and Therapy, found that participants who adhered to a daily mix of aerobic exercise and a mostly plant-based diet experienced slower cognitive decline. In contrast, memory and thinking worsened for members of a control group who did not change their habits.

Study Overview and Initial Results

The study, conceptualized by Dr. Dean Ornish, a physician and researcher known for his rigorous diet and lifestyle recommendations, involved 51 participants. Due to the COVID-19 pandemic, the study faced enrollment challenges but provided significant insights. The researchers observed that lifestyle changes might offer another way to combat Alzheimer’s, a disease affecting 6.9 million Americans. Despite extensive research and billions of dollars invested in developing drugs targeting beta-amyloid protein, only two drugs—Leqembi and Aduhelm—have received FDA approval. This new study suggests that lifestyle interventions could also reduce amyloid levels in patients, mirroring the effects of the amyloid-clearing drug Leqembi.

Lifestyle Changes and Their Impact

Participants in the study were divided into two groups: one adopting regular exercise and dietary changes and a control group that did not. The intervention group followed a strict plant-based diet, took eight supplements and vitamins, and engaged in daily 30-minute walks, strength training, and stress management activities such as meditation, yoga, or stretching.

To support these changes, participants and their caregivers attended four-hour Zoom sessions three times a week, which included supervised exercise, stretching, support groups, and lectures on lifestyle changes. The results showed that participants in the intervention group had better scores on Alzheimer’s tests compared to the control group. Specifically, three tests indicated improvement in cognition and function, while the fourth test showed less cognitive decline than the control group.

The study also reported that participants who adhered to the lifestyle changes had favorable beta-amyloid levels in their blood compared to the control group. Dr. Ornish, the study’s principal investigator, believes the findings demonstrate that lifestyle medicine can potentially combat Alzheimer’s disease.

Challenges and Future Directions

Despite the promising results, the study had limitations, including its small sample size and lack of racial and ethnic diversity among participants. Additionally, participants were aware of their involvement in the diet and lifestyle regimen, which might have influenced their expectations and outcomes. To mitigate the placebo effect, researchers informed participants that the effectiveness of the lifestyle changes was unknown.

Laura Baker, a professor at Wake Forest University School of Medicine, highlighted the need for larger studies to provide definitive answers. Both Baker and Ornish agree that maintaining heart health is crucial for long-term brain health. However, Baker cautions against premature claims that Alzheimer’s or other dementias can be reversed through diet and exercise. “The idea that lifestyle intervention can reverse dementia or cognitive impairment—I just don’t think there’s enough evidence for that,” she said. “And I think that’s creating false hope right now.”