If all of the article like the following are true, vegetarians must live forever...

Alzheimer's Researchers Find High Protein Diet Shrinks Brain
ScienceDaily (Oct. 21, 2009) — One of the many reasons to pick a low-calorie, low-fat diet rich in vegetables, fruits, and fish is that a host of epidemiological studies have suggested that such a diet may delay the onset or slow the progression of Alzheimer's disease (AD). Now a study published in BioMed Central's open access journal Molecular Neurodegeneration tests the effects of several diets, head-to-head, for their effects on AD pathology in a mouse model of the disease. Although the researchers were focused on triggers for brain plaque formation, they also found that, unexpectedly, a high protein diet apparently led to a smaller brain...
http://www.sciencedaily.com/re...10/091020192206.htm#

Interestingly, vegetable consumption has been linked to a lower incidence of Alzheimer's disease:

Vegetables, Not Fruit, Help Fight Memory Problems In Old Age
ScienceDaily (Oct. 24, 2006)
Eating vegetables, not fruit, helps slow down the rate of cognitive change in older adults, according to a study published in the October 24, 2006, issue of Neurology, the scientific journal of the American Academy of Neurology.

"Compared to people who consumed less than one serving of vegetables a day, people who ate at least 2.8 servings of vegetables a day saw their rate of cognitive change slow by roughly 40 percent. This decrease is equivalent to about 5 years of younger age."

Of the different types of vegetables consumed by participants, green leafy vegetables had the strongest association to slowing the rate of cognitive decline. The study also found the older the person, the greater the slowdown in the rate of cognitive decline if that person consumed more than two servings of vegetables a day. Surprisingly, the study found fruit consumption was not associated with cognitive change...
http://www.sciencedaily.com/re.../10/061024010707.htm

Eating a lot of tofu is actually not good for your memory.
http://www.medicalnewstoday.com/articles/114061.php#
I think it may depend on what the vegetarian actually eats. (I'm a vegetarian, but not one who actually eats many fruits and veggies).

I've tried to follow the McDougall diet, but it's so hard.

(The McDougall diet is essentially all complex carbohydrates, no dairy products, no animal protein, no animal fats, no refined oils.)

Once again, too me, it would be a much better idea to just do a survey of those that have been diagnosed with dementia that have been or are strict vegetarians.

Any diagnosed vegetarians out there?

Not us, gotta have those occasional Big Mac attacks.

Must you mention Big Macs when we're talking fruits and veggies and healthy diets? Next thing you know, someone will mention french fries, and I'll be a goner.

Been on twice daily red yeast rice extract for almost two weeks now, and started husband on once daily last Saturday. All is well (so far.)