Wednesday, August 12, 2009

Alzheimers and the "Greek Diet"

It's in the news: the "Greek Diet" prevents Alzheimer's disease. It drops the rate an astonishing 60% -- and that is probably under-estimated because the subjects, who were all urban-dwelling Americans, probably lied about how faithfully they followed the diet.

You'd think that the Greeks would have less Alzheimer's disease because they must eat the Greek diet, right?

Well no, a 1999 study on Alzheimers shows that the Greeks have the same Alzheimer's rate as everyone else. Perhaps the Greeks are modernizing like everyone else. However, real Greeks eating a traditional diet did have longer lifespan and less heart disease-- see below.

An 1999 study showing the Alzheimer's/diet connection was done at the University of Bari in Italy.

What is going on?

First of all, the Greek diet is characterized like this:
  • Increasing the amount of food consumed from plant sources, incuding fruits, vegetables, whole grains, legumes, nuts and seeds.
  • Emphasizing minimally processed and seasonally fresh/locally grown foods when possible.
  • Focusing on small portions of high quality food and eliminating low-nutrient-value snack foods
  • Using olive oil and other monounsaturated fats to replace other fats such as butter and margarine.
  • Reducing red meat consumption to a few times per month and eating fish and lean poultry a few times a week.
  • Getting regular physical activity
  • Optionally consuming a moderate amount of wine (one to two glasses) with meals.

One study showed that the benefits for real Greek people were different for each characteristic of the diet. The percentages reflect the healthfulness of each factor for increased lifespan.

>moderate ethanol consumption 23.5%,
>low consumption of meat and meat products 16.6%,
>high vegetable consumption 16.2%,
>high fruit and nut consumption 11.2%,
>high monounsaturated to saturated lipid ratio 10.6%,
>and high legume consumption 9.7%.
>High cereal consumption -- minimal benefit
> Low dairy -- minimal benefit
> high fish and seafood consumption - insignificant benefit

It is nice that this is a diet where alcohol is a HEALTH FOOD.

There are lots of studies talking about how healthy this Greek or Mediterranean diet is: less belly fat; inflammation; lower heart disease, and lower mortality.

So how does this work? It is well known that Alzheimer's is caused by the build-up of amyloid (starchy) plaques in the brain. It is unclear if the plaques grow where dead cells were, or if the plaques kill cells.

Alzheimer's researchers think that heart healthy behaviors help Alzheimer's too, but they don't understand how. It is possible the Greek diet is helping general healthfulness, or cardiac health, and these indirectly benefit Alzheimer's disease. The most recent study also showed exercise benefitted Alzheimer's too.