Animal protein linked to Alzheimer's by Framingham study

[Guest guest]

From today's Chronicle, page A5, by the New York Times service:

 

BUILDUP OF SPECIFIC AMINO ACID LINKED TO ALZHEIMER'S IN STUDY

 

People with high blood levels of homocysteine, a byproduct of a normal diet,

have twice the average risk of developing Alzheimer's disease, a study

published today in the New England Journal of Medicine finds.

 

The study, by researchers at Boston University and Tufts University,

suggests that other major degenerative conditions like cardiovascular

disease and diabetes may stem in part from diet, possibly making them

preventable.

 

Homocysteine is an amino acid, a building block of proteins. Its levels can

rise when people eat a diet heavy in animal protein and few fruits or leafy

vegetables, which lower the levels with folic acid and vitamins B6 and B12.

 

Studies are being planned to find out whether B vitamins can slow mental

decline in people with Alzheimer's, and scientists are recommending research

to determine whether the vitamins can prevent or delay dementia in healthy

people.

 

Although the study, whose participants were from the Framingham, Mass.,

Heart Study (which started in 1948), found a strong link between

homocysteine and dementia, it did not prove that the substance causes

dementia. Nonetheless, researchers say a causative role is plausible,

because homocysteine can damage blood vessels and nerves, and it has been

linked to strokes and heart attacks.

 

The new study is the first to find a connection between high homocysteine

levels in healthy people and the later development of Alzheimer's.

[Guest guest]

This article has a number of misunderstandings about homocysteine...

 

> BUILDUP OF SPECIFIC AMINO ACID LINKED TO ALZHEIMER'S IN STUDY

>

> People with high blood levels of homocysteine, a byproduct of a normal diet,

> have twice the average risk of developing Alzheimer's disease, a study

> published today in the New England Journal of Medicine finds.

>

> The study, by researchers at Boston University and Tufts University,

> suggests that other major degenerative conditions like cardiovascular

> disease and diabetes may stem in part from diet, possibly making them

> preventable.

>

> Homocysteine is an amino acid, a building block of proteins.

 

Homocysteine is an amino acid, but is not a building block of proteins. It

is a byproduct of methionine (another amino acid found in all diets)

metabolism. If you don't have enough folate and B12 (and to a lesser extent

B6), homocysteine will build up in your blood and (most likely) damage

arteries.

 

> Its levels can

> rise when people eat a diet heavy in animal protein and few fruits or leafy

> vegetables, which lower the levels with folic acid and vitamins B6 and B12.

 

The fruits and leafy vegetables provide folate, not B12. B6 is found in a

wide variety of foods (including plants and animal products). However, B6 is

normally only a problem for high homocysteine in people who have B6-related

metabolic problems.

 

Vegans who do not supplement with B12 generally have higher homocysteine

levels than do meat eaters (with lacto-ovo vegetarians in the middle). So,

it is important for vegans to supplement with B12 to keep their homocysteine

levels low. For more information see:

 

An Open Letter from Health Professionals and Vegan Organizations

What Every Vegan Should Know about Vitamin B12

 

http://veganoutreach.org/health/b12letter.html

 

Jack