Diet high in methionine could increase risk of Alzheimer's

December 16, 2009

A diet rich in methionine, an amino acid typically found in red meats, fish, beans, eggs, garlic, lentils, onions, yogurt and seeds, can possibly increase the risk of developing Alzheimer's disease, according to a study by Temple researchers.

The researchers published their findings, titled "Diet-induced hyperhomocysteinemia increases Amyloid-β formation and deposition in a mouse model of Alzheimer's disease," in the journal Current Alzheimer Research.

"When methionine reaches too high a level, our body tries to protect itself by transforming it into a particular amino acid called homocysteine," said lead researcher Domenico Praticò, an associate professor of pharmacology in the School of Medicine. "The data from previous studies show -- even in humans -- when the level of homocysteine in the blood is high, there is a higher risk of developing dementia. We hypothesized that high levels of homocysteine in an animal model of Alzheimer's would accelerate the disease."

Using a seven-month old mouse model of the disease, they fed one group an eight-month diet of regular food and another group a diet high in methionine. The mice were then tested at 15 months of age -- the equivalent of a 70-year-old human.

"We found that the mice with the normal diet had normal homocysteine levels, but the mice with the high methionine diet had significantly increased levels of homocysteine, very similar to human subjects with hyperhomocysteinemia," said Praticò. "The group with the high methionine diet also had up to 40 percent more amyloid plaque in their brains, which is a measurement of how much Alzheimer's disease has developed.

The researchers also examined capacity to learn a new task and found it diminished in the group with the diet high in methionine.

Still, Praticò emphasized, methionine is an essential amino acid for the human body and "stopping one's intake of methionine won't prevent Alzheimer's. But people who have a diet high in red meat, for instance, could be more at risk because they are more likely to develop this high level of circulating homocysteine," he said.
-end-
In addition to Praticò, other researchers working on the study included Jia-Min Zhuo and Hong Wang from Temple's Department of Pharmacology, Thomas J. Gould and George S. Portugal from Temple's Department of Psychology, and Warren D. Kruger from the Fox Chase Cancer Center.

The study was funded by grants from the National Institute of Health and the Alzheimer's Association, in addition to support from Pennsylvania Commonwealth through the Fox Chase Cancer Center.

Temple University

Related Diet Articles from Brightsurf:

What's for dinner? Dolphin diet study
More evidence has emerged to support stricter coastal management, this time focusing on pollution and overfishing in the picturesque tourist waters off Auckland in New Zealand.

Can your diet help protect the environment?
If Americans adhere to global dietary recommendations designed to reduce the impact of food production and consumption, environmental degradation could be reduced by up to 38%, according to a new paper published in the journal Environmental Justice.

Diet may help preserve cognitive function
According to a recent analysis of data from two major eye disease studies, adherence to the Mediterranean diet - high in vegetables, whole grains, fish, and olive oil -- correlates with higher cognitive function.

Diet quality of young people in US
This observational study used national survey data from young people up to age 19 to estimate the overall diet quality of children and teens in the United States and to explore how diet quality has changed from 1999 to 2016.

The keto diet can lead to flu-like symptoms during the first few weeks on the diet
A ketogenic diet can lead to several flu-like symptoms within the first few weeks on the diet.

Reconstructing the diet of fossil vertebrates
Paleodietary studies of the fossil record are impeded by a lack of reliable and unequivocal tracers.

Your gums reveal your diet
Sweet soft drinks and lots of sugar increase the risk of both dental cavities and inflammation of the gums -- known as periodontal diseases -- and if this is the case, then healthy eating habits should be prioritized even more.

Poor diet can lead to blindness
An extreme case of 'fussy' or 'picky' eating caused a young patient's blindness, according to a new case report published today [2 Sep 2019] in Annals of Internal Medicine.

New research on diet and supplements during pregnancy and beyond
The foods and nutrients a woman consumes while pregnant have important health implications for her and her baby.

Special issue: Diet and Health
Diet has major effects on human health. In this special issue of Science, 'Diet and Health,' four Reviews explore the connections between what we eat and our well-being, as well as the continuing controversies in this space.

Read More: Diet News and Diet Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.