High Homocysteine

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High Homocysteine

 

Also indexed as: Hyperhomocysteinemia

http://www.evitamins.com/healthnotes.asp?ContentID=1029002

 

Homocysteine, a normal breakdown product of the essential amino

acidmethionine, is believed to exert several toxic effects.

 

A growing body of evidence suggests that an elevated homocysteine

level is a risk factor for heart disease, independent of other known

risk factors, such as elevated serum cholesterol and hypertension.1

2 The evidence is not all one-sided, however. In some research the

link has appeared only in women,3 and a few scientists still have

doubts about the importance of elevations in homocysteine for

anyone.4 The clear association between elevated homocysteine levels

and heart disease reported in most studies5 does not conclusively

prove that homocysteine causes heart disease. It might only be a

marker for something else that is the real culprit.6 Nonetheless,

many cardiologists take seriously the association between elevations

in homocysteine and increased risk of heart disease.

 

Anger and hostility correlate with the risk of heart disease.7 8 A

preliminary study found a link between high homocysteine levels and

hostility and repressed anger.9 While anger, hostility, high

homocysteine, and heart disease all appear to be tied together,

which of these is cause and which is effect remains somewhat unclear.

 

Increased homocysteine levels may also be a risk factor for the

development of many other conditions, including stroke,10

thromboembolism11 (blood clots that can dislodge and cause stroke,

heart attack, and other complications), osteoporosis,12 inflammatory

bowel disease (Crohn's disease and ulcerative colitis),13

Alzheimer's disease,14 death from diabetes,15 miscarriage,16 17 18

19 20 other complications of pregnancy,21 22 23 24 25 and

hypothyroidism.26

 

Scientists have yet to prove that elevated homocysteine levels cause

any of these diseases. However, most doctors believe that high

homocysteine increases the risk of at least heart disease.

Fortunately, homocysteine levels can easily be reduced with safe and

inexpensive B vitamin supplementation. (See " Nutritional supplements

that may be helpful " below.)

 

Checklist for High Homocysteine

 

Rating Nutritional Supplements Herbs

Folic acid, vitamin B6, and vitamin B12 (in combination)

 

Betaine (trimethylglycine)

 

Choline

 

Reliable and relatively consistent scientific data showing a

substantial health benefit.

Contradictory, insufficient, or preliminary studies suggesting a

health benefit or minimal health benefit.

For an herb, supported by traditional use but minimal or no

scientific evidence. For a supplement, little scientific support

and/or minimal health benefit.

 

What are the symptoms of high homocysteine?

Extremely high homocysteine can cause blood clots, rapid bone loss,

and, in children, mental retardation. But in general, high

homocysteine does not cause symptoms until and unless one of the

diseases with which it is associated, appears.

 

Medical treatments

Over the counter supplementation with B-complex vitamins containing

vitamin B6, vitamin B12, and folic acid is recomended.

 

People with high homocysteine are typically advised to reduce their

consumption of processed foods, meat, and saturated fats, because

these dietary changes lower the risk of heart disease.

 

Dietary changes that may be helpful

Since homocysteine is produced from methionine, intake of large

amounts of methionine would presumably increase homocysteine levels.

Indeed, ingestion of supplemental methionine is used experimentally

as a way to increase homocysteine levels.27 Foods high in methionine

that have also been linked with an increased risk of heart disease

include meat and eggs. The extent to which consumption of these

foods affects the risk of heart disease as a result of their

methionine content remains unknown.

 

A controlled trial showed that eating a diet high in fruits and

vegetables containing folic acid, beta-carotene and vitamin C

effectively lowered homocysteine levels.28 Healthy people were

assigned to either a diet containing a pound of fruits and

vegetables per day, or to a diet containing three and a half ounces

of fruits and vegetables per day. After four weeks, those eating the

higher amount of fruits and vegetables had an 11% lower homocysteine

level compared with those eating the lower amount of fruits and

vegetables.

 

Another study of men with heart disease demonstrated that

consumption of whole-grain and legume powder at breakfast, instead

of their usual breakfast of refined rice, resulted in a significant

reduction in homocysteine levels.29

 

Lifestyle changes that may be helpful

According to a recent study, both cigarette smoking and coffee

consumption were associated with increased homocysteine levels.30

These findings are consistent with studies that have found both

smoking and caffeine consumption to be associated with an increased

risk of both cardiovascular disease and osteoporosis. The link

between coffee and increased homocysteine has been confirmed by some

researchers,31 but not others.32

 

In one study, a diverse group of people participated in a week-long

program that included a strict vegan diet, stress management and

spirituality enhancement sessions, group support, and exclusion of

tobacco, alcohol, and caffeine.33 B vitamin supplements known to

reduce blood homocysteine levels were not provided. After only one

week in the program, the average homocysteine level fell 13%.

 

Nutritional supplements that may be helpful

Vitamin B6, folic acid, and vitamin B12 all play a role in

converting homocysteine to other substances within the body. By so

doing, they consistently lower homocysteine levels in research

trials,34 35 36 a finding that is now well accepted. Several studies

have used (and some doctors recommend) 400–1,000 mcg of folic acid

per day, 10–50 mg of vitamin B6 per day, and 50–300 mcg of vitamin

B12 per day.

 

Of these three vitamins, folic acid supplementation lowers

homocysteine levels the most for the average person.37 38 It also

effectively lowers homocysteine in people on kidney dialysis.39 In

1996, the FDA required that all enriched flour, rice, pasta,

cornmeal, and other grain products contain 140 mcg of folic acid per

3½ ounces.40 This level of fortification has led to a measurable

decrease in homocysteine levels.41 However, even higher levels of

food fortification with folic acid have been reported to be more

effective in lowering homocysteine,42 suggesting that the FDA-

mandated supplementation is inadequate to optimally protect people

against high homocysteine levels. Therefore, people wishing to lower

their homocysteine levels should continue to take folic acid

supplements despite the FDA-mandated fortification program.

 

Betaine (trimethylglycine) (6 grams per day)43 and choline (2 grams

per day)44 have each been shown to lower homocysteine levels.

Doctors usually consider supplementation with these nutrients only

when supplementation with folic acid, vitamin B6, and vitamin B12 do

not reduce homocysteine levels sufficiently.