Scientists have discovered that a high fat, low carbohydrate diet improves Alzheimer's disease in mice and say the study results may also have implications for dieters.
The researchers found that mice bred with the mouse version of Alzheimer's disease showed improvements in their condition when treated with a high-fat, low-carbohydrate diet.
The recently published report showed that a brain protein, amyloid-beta, which is an indicator of Alzheimer's disease, was reduced in mice on the so-called ketogenic diet.
The finding by Samuel Henderson, from Accera, Inc., Colorado and colleagues from Belgium, contradict previous studies suggesting a negative effect of fat on Alzheimer's disease.
The authors say their work supports the premise that key aspects of Alzheimer's disease can be altered by changes in metabolism, and also highlights the 'interaction of dietary components and how such components influence the metabolic state'.
The authors believe that insulin and the related hormone, insulin-related growth factor-1 (IGF-1), are the key players.
Insulin, which is often regarded as a storage hormone, since it promotes deposition of fat, may also work to encourage amyloid-beta production.
According to Richard Feinman, editor of the journal Nutrition and Metabolism, who explains the relation between nutrients, that if fat is the bomb, then insulin (from carbohydrate) is the fuse.
Most studies of the harmful effects of fat have been done in the presence of high carbohydrate.
If carbs are high, dietary fat is not oxidized and is instead stored as body fat.
However when carbohydrates are very low and fat is high, compounds called ketone bodies are generated (ketosis) and these compounds may play a role in the reduction seen in amyloid-beta.