Antioxidant Vitamins for Heart Disease Prevention - Helpful or Harmful?
"A vitamin is a substance that makes you ill if you don't eat it.
" Albert Szent-Gyorgyi Several international scientific studies have found afavorable relationship between antioxidant vitamins and heart diseaase.
Antioxidant supplements include ascorbic acid (vitamin C), a-tocopherol (vitamin E), folate, ß-carotene (a vitamin A precursor), ubiquinone (coenzyme Q10), bioflavonoids and selenium.
The most commonly used vitamins are vitamin C and E.
Vitamin C is a water-soluble vitamin.
It helps the growth and repair of tissues in the body.
It helps form collagen, an important protein used to make skin, scar tissue, tendons, ligaments, and blood vessels.
Vitamin C is also essential for the healing of wounds, and for the repair and maintenance of cartilage, bones, and teeth.
Foods that tend to be the highest sources of vitamin C include green peppers, citrus fruits and juices, strawberries, tomatoes, broccoli, turnip greens and other leafy greens, sweet and white potatoes, and cantaloupe.
Other excellent sources include papaya, mango, watermelon, brussels sprouts, cauliflower, cabbage, winter squash, red peppers, raspberries, blueberries, cranberries, and pineapples.
Vitamin E is fat soluble and has antioxidant properties.
It is found in vegetable and seed oils, in wheat germ and, in smaller quantities, in meats, fish, fruits and vegetables.
Beta carotene has antioxidant, immuno-modulatory, anti-carcinogenic and anti-atherogenic activity.
It is found in dietary carotenoids including fruits, yellow-orange vegetables (e.
g.
, carrots, squash and sweet potatoes) and deep-green vegetables (e.
g.
, spinach and broccoli).
In 1985, Verlangieri and associates reported in Med Hypotheses that people who had a higher consumption of fruits and vegetables had lower death rates from coronary heart disease.
Riemersma and associates in 1991 reported in the Lancet that angina patients had lower plasma vitamin E levels when compared to controls.
An inverse relationship between plasma vitamin E levels and coronary heart disease mortality was also established in a report published by Luoma and colleagues from Northern Finland, in 1995.
The National Health and Nutrition Examination Survey-I cohort study found an inverse relationship between the highest vitamin C intake (diet and supplements) and coronary heart disease risk over 10 years in 11,349 U.
S.
men and women 25 to 74 years of age.
This data was published in Epidemiology in 1992.
The heart protective effects of vitamin C was again suggestedin 1994, when Knekt's group found an inverse relationship between vitamin C intake and coronary mortality in an epidemiology study, and reported these findings in the American Journal of Epidemiology.
Oxidation of the harmful low-density lipoprotein (LDL)is the key factor leading to the development of atherosclerosis.
This leads to plaque formation and progression to rupture or coronary artery blockage and an eventual heart attack.
The LDL oxidation can be reduced by antioxidants in plasma, the LDL particle and the cell wall.
Vitamins E and B-carotene are the major fat-soluble antioxidant vitamins.
Vitamin C is the major water-soluble antioxidant.
By reducingLDL oxidation, atherosclerosis progression should be retarded, and perhaps regressed.
Antioxidants alsoimprove arterial wall reactivity and increase endothelial nitric oxide release.
Both these effects are beneficial to the circulation.
Based on these research studies,the medical community started recommendingvitamin E in a dosage of 400 IU per day and vitamin C in a dosage of 500 to 1,000 mg per day, as a beneficial supplement for coronary heart disease.
However subsequent larger and better organized studies fail to confirm benefits.
A meta-analysis of 68 randomized trials which included over 230,000 participants was published in the February 28, 2007 issue of the Journal of the American Medical Association..
The group led by Goran Bjelakovic, MD, of the Copenhagen University Hospital in Denmark, reported that pooled data showed that supplemental intake of vitamin A, beta-carotene and vitamin E appeared to have a surprise association with increased deaths.
Intake of vitamin C or selenium was neither harmful nor helpful, when heart disease was concerned.
B-carotene had previously been found unfavorable for smokers.
Although folate supplementation reduces serum homocysteine levels, adequate trials focusing on CHD events have not been completed.
High levels of serum homocysteine are associated with coronary heart disease.
Ubiquinone, flavonoids, garlic and other supplements have not been adequately tested for CHD event reduction, appropriate dosing, reliability or long-term safety.
"I don't need rejuvenation.
One vitamin E pill, and I'm okay.
" Actor William Shatner.
Vitamins have many other beneficial effects.
But what is the verdict on vitamins and heart disease? It seems that naturally packaged vitamin C and vitamin E are heart protective.
When packaged in pills, liquid or capsules, they somehow become harmful.
So listen to the American Heart Association.
Until further scientific evidence on antioxidant supplementation is available, the best source of anti-oxidants remains a well-balanced diet high in fruits, vegetables, and whole grains.
" Albert Szent-Gyorgyi Several international scientific studies have found afavorable relationship between antioxidant vitamins and heart diseaase.
Antioxidant supplements include ascorbic acid (vitamin C), a-tocopherol (vitamin E), folate, ß-carotene (a vitamin A precursor), ubiquinone (coenzyme Q10), bioflavonoids and selenium.
The most commonly used vitamins are vitamin C and E.
Vitamin C is a water-soluble vitamin.
It helps the growth and repair of tissues in the body.
It helps form collagen, an important protein used to make skin, scar tissue, tendons, ligaments, and blood vessels.
Vitamin C is also essential for the healing of wounds, and for the repair and maintenance of cartilage, bones, and teeth.
Foods that tend to be the highest sources of vitamin C include green peppers, citrus fruits and juices, strawberries, tomatoes, broccoli, turnip greens and other leafy greens, sweet and white potatoes, and cantaloupe.
Other excellent sources include papaya, mango, watermelon, brussels sprouts, cauliflower, cabbage, winter squash, red peppers, raspberries, blueberries, cranberries, and pineapples.
Vitamin E is fat soluble and has antioxidant properties.
It is found in vegetable and seed oils, in wheat germ and, in smaller quantities, in meats, fish, fruits and vegetables.
Beta carotene has antioxidant, immuno-modulatory, anti-carcinogenic and anti-atherogenic activity.
It is found in dietary carotenoids including fruits, yellow-orange vegetables (e.
g.
, carrots, squash and sweet potatoes) and deep-green vegetables (e.
g.
, spinach and broccoli).
In 1985, Verlangieri and associates reported in Med Hypotheses that people who had a higher consumption of fruits and vegetables had lower death rates from coronary heart disease.
Riemersma and associates in 1991 reported in the Lancet that angina patients had lower plasma vitamin E levels when compared to controls.
An inverse relationship between plasma vitamin E levels and coronary heart disease mortality was also established in a report published by Luoma and colleagues from Northern Finland, in 1995.
The National Health and Nutrition Examination Survey-I cohort study found an inverse relationship between the highest vitamin C intake (diet and supplements) and coronary heart disease risk over 10 years in 11,349 U.
S.
men and women 25 to 74 years of age.
This data was published in Epidemiology in 1992.
The heart protective effects of vitamin C was again suggestedin 1994, when Knekt's group found an inverse relationship between vitamin C intake and coronary mortality in an epidemiology study, and reported these findings in the American Journal of Epidemiology.
Oxidation of the harmful low-density lipoprotein (LDL)is the key factor leading to the development of atherosclerosis.
This leads to plaque formation and progression to rupture or coronary artery blockage and an eventual heart attack.
The LDL oxidation can be reduced by antioxidants in plasma, the LDL particle and the cell wall.
Vitamins E and B-carotene are the major fat-soluble antioxidant vitamins.
Vitamin C is the major water-soluble antioxidant.
By reducingLDL oxidation, atherosclerosis progression should be retarded, and perhaps regressed.
Antioxidants alsoimprove arterial wall reactivity and increase endothelial nitric oxide release.
Both these effects are beneficial to the circulation.
Based on these research studies,the medical community started recommendingvitamin E in a dosage of 400 IU per day and vitamin C in a dosage of 500 to 1,000 mg per day, as a beneficial supplement for coronary heart disease.
However subsequent larger and better organized studies fail to confirm benefits.
A meta-analysis of 68 randomized trials which included over 230,000 participants was published in the February 28, 2007 issue of the Journal of the American Medical Association..
The group led by Goran Bjelakovic, MD, of the Copenhagen University Hospital in Denmark, reported that pooled data showed that supplemental intake of vitamin A, beta-carotene and vitamin E appeared to have a surprise association with increased deaths.
Intake of vitamin C or selenium was neither harmful nor helpful, when heart disease was concerned.
B-carotene had previously been found unfavorable for smokers.
Although folate supplementation reduces serum homocysteine levels, adequate trials focusing on CHD events have not been completed.
High levels of serum homocysteine are associated with coronary heart disease.
Ubiquinone, flavonoids, garlic and other supplements have not been adequately tested for CHD event reduction, appropriate dosing, reliability or long-term safety.
"I don't need rejuvenation.
One vitamin E pill, and I'm okay.
" Actor William Shatner.
Vitamins have many other beneficial effects.
But what is the verdict on vitamins and heart disease? It seems that naturally packaged vitamin C and vitamin E are heart protective.
When packaged in pills, liquid or capsules, they somehow become harmful.
So listen to the American Heart Association.
Until further scientific evidence on antioxidant supplementation is available, the best source of anti-oxidants remains a well-balanced diet high in fruits, vegetables, and whole grains.