A new study certainly offers ammo for vegetarians, vegans, and PETA-types. People who eat a lot of meat could be putting themselves at risk of dementia and a range of other conditions, due to a chemical, called advanced glycation end products (AGEs), that is already present in meat, and produced while cooking it too.
Animal-derived foods that are high in protein and fat typically contain high levels of AGEs as well. Cooking them, however, can cause chemical reactions as the meat browns. These reactions, known as the Maillard Reaction, occur when the sugars and amino acids — proteins, fats, and nucleic acids — on the surface of the meat combine from the heat or flame. The longer the meat is exposed to heat, the more AGEs, which are also called glycotoxins, are produced. Although AGEs form within the body too, high levels of the chemicals can become pathogenic, according to an article published in the Journal of the American Dietetic Association. AGEs have been implicated in the onset of diabetes, cardiovascular disease, and kidney disease because of their ability to cause oxidative stress and inflammation within cells.
Researchers of the current study, which was published in Proceedings of the National Academy of Sciences, found that, in mice, high-AGE diets contributed to a deficiency in the protein SIRT1, which is associated with a decreased insulin sensitivity. This, in turn led to metabolic syndrome, an umbrella term for a range of risk factors that can lead to heart disease and diabetes. The mice also develop beta amyloid deposits — a major contributor to Alzheimer’s — in their brains causing them to experience cognitive and motor deficits. Going further, the researchers compared these results to data of older adults who ate a lot of AGEs, and found similar that many of them had impaired cognition and a lower insulin sensitivity as well.
Though the study probably won’t get all meat eaters to quit eating meat — its researchers emphasize that the findings aren’t definitive yet — it suggests that older adults who are at risk of Alzheimer’s may want to consider changing their diets. “The findings are very promising, but the question that needs to be answered is whether cutting down on glycotoxins can prevent or reverse dementia,” said Helen Vlassara, the study leader from the Icahn School of Medicine at Mount Sinai Hospital in New York, according to The Guardian.
Eliminating AGEs from diets wouldn’t necessarily be difficult either. People who wish to do so should increase their consumption of fish, legumes, low-fat milk, vegetables, fruits, and whole grains. They should also reduce their intake of solid fats, fatty meats, full-fat milk, and processed food. “People will grill bacon and fry eggs for breakfast, or have a toasted bagel or muffin,” Vlassara said. “But they could boil or poach the eggs, and have fresh juice with bread. With meat, we recommend stewing and boiling, making sauces instead of exposing meat to very dry heat.”
Source: Cai W, Uribarri J, Vlassara H, et al. Oral glycotoxins are a modifiable cause of dementia and the metabolic syndrome in mice and humans. PNAS. 2014.