(NaturalNews) For muscle heads, diets high in protein may be just what the doctor ordered, but a growing bicep may come with a cost: a shrinking brain.
Alzheimer's disease researchers are well aware of the wealth of studies linking diet to brain health. The Mediterranean diet, for example, is touted as one of the best diets to follow not only for great physical health, but for great mental health as well, according to findings published in a December 2006 issue of the Archives of Neurology.
With this in mind, researchers put four specific diets to the test to see how, or if, they contributed to the formation of amyloid proteins in the brain. Amyloid protein formation is one of the precursors to Alzheimer's disease.
Using rats as their specimens, the researchers provided each rat with one of four regimented diets: a high fat, low carbohydrate diet; a low fat, high carbohydrate diet; a diet high in protein but low in carbohydrates; or a diet where carbohydrates, fats and protein were well-balanced (i.e., 40 percent carbohydrate, 30 percent fat, 30 percent protein).
After 14 weeks of observing and feeding the genetically-modified rats, the researchers performed several post-mortem procedures, including an analysis on their brains to see if some developed better than others.
There wasn't much of a difference in the brain development of most of the brains, with the noted exception of the rats fed the high protein diet. For them, not only was the hippocampus region less developed – the portion of the brain most adversely affected by Alzheimer's – but their brains weighed less, five percent less.
Researchers believe their findings could affect what people eat and at what age, as the likelihood of developing Alzheimer's dramatically increases after the age of 65. But until more human studies are done, the researchers are loath to recommend any specific diet.
That said, this study adds to a growing body of evidence suggesting how someone eats plays a crucial role in assessing risk for Alzheimer's disease. At present, though, researchers consider age (i.e., Alzheimer's risk doubles every five years after age 65), genetics (i.e., the gene apolipoprotein E-e4 is the only known gene associated with Alzheimer's disease risk) and family history as the biggest factors.
It is estimated that 5.3 million Americans are currently living with Alzheimer's, overwhelmingly among those 65 years of age and older (200,000 are believed to be younger than 65). Alzheimer's has recently jumped from seventh to the sixth leading cause of death in the U.S. While no one is immune to it, Alzheimer's diagnoses are higher among women than men (approximately 17 percent of women age 71 and older have Alzheimer's disease compared to 12 percent of men 71 and older).