Could a low protein diet help humans with Alzheimer's disease?
Researchers have been trying to find dietary interventions that could prevent and even treat Alzheimer's disease. One nutritional approach might be a combination of omega-3 fatty acids and vitamin D, found in a recent study. A new finding highlights potential treatment from a low-protein diet that was found to halt progression of the disease in mice.
For their study, researchers from University of Southern California fed mice a low-protein diet supplemented with amino acids for four weeks. Mice that were in advanced stages of Alzheimer's disease showed signs of improved memory compared to a control group.
According to the scientists, eating a low protein diet keeps levels of the growth hormone IGF-1 lower. The hormone is linked to cancer, diabetes, heart disease and aging. The researchers previously found humans deficient in IGF-1 had lower incidences of cancer and diabetes, leading them to investigate the effect diet might have on improving Alzheimer's disease.
USC Professor Valter Longo, the study's corresponding author said in a press release, "Although the new study is in mice, it raises the possibility that low protein intake and low IGF-I may also protect from age-dependent neurodegeneration."
Mice given the lower protein diet were able to find their way through a maze. The researchers also say the mice given the special diet had fewer damaged brain neurons that comes from high levels of damaged protein, called "tau".
Pinchas Cohen, dean of the USC Davis School who also worked on the study says it's important to find ways to treat the Alzheimer's disease that is expected to become a major burden from an aging population.
He explains it can take years to develop drugs to treat the disease, making it important to find new approaches to address the problem.
Other potential natural interventions for Alzheimer's disease that show promise include vitamin E, grape seed extract, coffee and curcumin found in the Indian spice turmeric.
More studies are needed to determine if a low protein diet can help humans with Alzheimer's disease. The researchers say the diet may not be safe for elderly people who might already be frail and have lost weight. The protein restricted diet was given to mice every other week for four weeks and just might be an option worth trying for humans, but only under strict supervision of a physician.
University of Southern California
February 13, 2013
Updated August 29, 2015