ANTIOXIDANTS: Overview, Uses, Side Effects, Precautions, Interactions, Dosing and Reviews

Overview

Antioxidants are ingredients thought to reduce the effects of free radicals. Free radicals are substances that cause oxidative stress, which may contribute to aging and certain diseases. Taking antioxidants is thought to counteract these effects.

Fruits and vegetables contain antioxidants. Eating more fruits and vegetables usually has benefit for disease. But there's limited evidence to know whether antioxidant supplements help to prevent disease.

Antioxidants don't seem to help with various cancers or heart disease. Antioxidants have been tried for asthma, kidney disease in people with diabetes, and many other conditions, but there is no good evidence to support these uses.

How does it work ?

Antioxidants are chemicals that seem to reduce "oxidative stress." Oxidative stress is thought to worsen many different conditions such as cancer and heart disease.

Uses & Effectiveness ?

Possibly Ineffective for

Bladder cancer. Taking antioxidants doesn't seem to reduce the risk of bladder cancer.
Cancer. Taking antioxidants doesn't seem to prevent cancer or death from cancer.
Cataracts. Taking antioxidants for up to 8 years doesn't seem reduce the risk of cataracts or cataract surgery.
Colon cancer, rectal cancer. Taking antioxidants doesn't seem to reduce the risk of colon or rectal cancer.
Heart disease. Antioxidant-containing fruits and vegetables have been linked with a lower risk of death in people with heart disease. But taking antioxidant supplements doesn't seem to reduce the risk of heart attack, stroke, or heart death in people with heart disease.
Nonmelanoma skin cancer. Taking antioxidants doesn't seem to reduce the risk of nonmelanoma skin cancer.
Prostate cancer. Taking antioxidants doesn't seem to reduce the risk of prostate cancer.

Insufficient Evidence for

An eye disease that leads to vision loss in older adults (age-related macular degeneration or AMD). Antioxidants don't seem to prevent AMD. But certain combinations of antioxidants might help prevent AMD from getting worse.
Lou Gehrig's disease (amyotrophic lateral sclerosis or ALS). Early research shows that antioxidant supplements don't improve survival in people with ALS.
Asthma. People who get lower amounts of antioxidant vitamins in their diet seem to have a greater risk of asthma.
Cancer of the cervix. People who get more antioxidants from their diet or supplements seem to have a lower risk of cervical cancer.
Cystic fibrosis. In general, antioxidant vitamins don't seem to improve lung function in people with cystic fibrosis. But the antioxidant glutathione might have some benefit.
Kidney damage in people with diabetes (diabetic nephropathy). Antioxidants might improve some markers of kidney disease in people with diabetes. But they don't seem to affect its progression.
Conditions in a man that prevent him from getting a woman pregnant within a year of trying to conceive (male infertility). Antioxidants don't seem to improve pregnancy rates in men that have received a surgery called varicocelectomy.
Build up of fat in the liver in people who drink little or no alcohol (nonalcoholic fatty liver disease or NAFLD). It's unclear if antioxidants are beneficial in people with NAFLD.
Death from any cause. There is mixed evidence about the effects of antioxidant supplementation on death from any cause.
Swelling (inflammation) of the pancreas (pancreatitis). Antioxidants might reduce hospital stay in acute pancreatitis. Antioxidants might also reduce pain in chronic pancreatitis. But they don't seem to prevent complications of pancreatitis.
Recovery after surgery. Research shows that certain antioxidants seem to reduce irregular heart beat and hospital stay after heart surgery.
A pregnancy complication marked by high blood pressure and protein in the urine (pre-eclampsia). Antioxidants don't seem to prevent pre-eclampsia in pregnant women.
Schizophrenia. Giving antioxidants with conventional medicine doesn't seem to further improve overall symptoms in people with schizophrenia.

View References

REFERENCES:

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CONDITIONS OF USE AND IMPORTANT INFORMATION: This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances. Never delay or disregard seeking professional medical advice from your doctor or other qualified health care provider because of something you have read on WebMD. You should always speak with your doctor or health care professional before you start, stop, or change any prescribed part of your health care plan or treatment and to determine what course of therapy is right for you.

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© Therapeutic Research Faculty 2020.

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ANTIOXIDANTS

Overview

How does it work ?

Uses & Effectiveness ?

Possibly Ineffective for

Insufficient Evidence for

Side Effects

Special Precautions and Warnings

Interactions ?

Dosing

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