Last year, we posted news of an epigenetic diet rich in broccoli, cauliflower, cabbage, fava beans and kale that claimed to reduce cancer and degenerative brain changes. Despite its alleged health benefits, the diet has found few followers among your average American carnivore.
And although it’s unlikely that we will ever see nutritionists advocating a hamburger, beer and potato chip diet, maybe more people will be tempted to reduce their risk of Alzheimer’s disease and memory problems by following the dietary advice of a new study published in the May 2, 2012, online issue of Neurology®.
This research showed shows that eating foods such as fish, chicken, salad dressing and nuts, which contain omega-3 fatty acids, is associated with lower blood levels of beta-amyloid, a protein related to Alzheimer’s.
The study followed 1,219 people 65 and older, who were free of dementia. Participants, provided information about their diet for an average of 1.2 years before their blood was tested for beta-amyloid.
The researchers looked specifically at 10 nutrients, including saturated fatty acids, omega-3 and omega-6 polyunsaturated fatty acids, mono-unsaturated fatty acid, vitamin E, vitamin C, beta-carotene, vitamin B12, folate and vitamin D.
They found that the more omega-3 fatty acids a person ate, the lower their blood beta-amyloid levels. Consuming one gram of omega-3 per day – the equivalent of approximately half a fillet of salmon per week, lowered blood beta-amyloid levels by 20-30%.
“It was a continuous association. More and more intake of omega-3s was associated with lower and lower levels of beta-amyloid in the blood. There was no threshold effect,” author Nikolaos Scarmeas, MD, from Columbia University Medical Center
The association between omega-3 consumption and beta-amyloid was unaffected by whether or not a person took supplements – meaning if two people consumed the same amount of omega-3s, one through food and the other through supplements, the person who consumed more omega-3 rich foods typically had lower blood levels of beta-amyloid.
Other nutrients were not associated with changes in plasma beta-amyloid levels. And results stayed the same after adjusting for age, education, gender, ethnicity, amount of calories consumed and presence of the APOE gene, a risk factor for Alzheimer’s disease.
The beneficial impact of omega-3 on brain health would fall in line with past studies of the nutrient. “Previous studies have suggested that omega-3s and other aspects of diet may be related to brain function,” Scarmeas said. “Here we demonstrate one possible mechanism could be through amyloid, the main biological mechanism that relates to Alzheimer’s disease.”
Scarmeas speculated that omega-3s may be able to reduce oxidative stress on the brain and the resulting vascular damage, or even have some kind of impact on beta-amyloid in the brain.
And although there is not enough data yet to suggest omega 3’s and beta-amyloid are directly related, I, for one, will be ordering the pecan crusted chicken salad for lunch today, dressing on the plate!