- What other names is Fish Oil known by?
- What is Fish Oil?
- Is Fish Oil effective?
- How does Fish Oil work?
- Are there safety concerns?
- Are there any interactions with medications?
- Dosing considerations for Fish Oil.
Fish Oil Safety and Side Effects
Fish oil is safe for most people. It can cause side effects including belching, bad breath, heartburn, nausea, loose stools, rash, and nosebleeds. Taking fish oil supplements with meals or freezing them can often decrease these side effects. Some fish meats are contaminated with mercury and other industrial and environmental chemicals. Fish oil supplements typically do not contain these contaminants.
Taking fish oil supplements can increase levels of the "bad" LDL cholesterol in some people. You will need blood tests periodically to ensure LDL cholesterols do not become too high.
High doses of fish oil might keep blood from clotting and can INCREASE the chance of bleeding.
Do not take fish oil if:
- You have liver disease.
- You are allergic to fish or seafood.
- You have a condition called bipolar disorder.
- You have an implantable defibrillator (a surgically placed device to prevent irregular heartbeat).
There is some scientific evidence that fish oils might have other benefits for the heart. Fish oils seem to help to prevent a second heart attack if started within hours of the first attack and continued for a year. Fish oils might also lower blood pressure in some people who have high blood pressure.
Fish oils might also be helpful for rheumatoid arthritis. People with rheumatoid arthritis seem to be less stiff in the morning if they take fish oils.
There is also some evidence that fish oils can help prevent migraine headaches in some people.
However, fish oils do not help atherosclerosis or "hardening of the arteries." They also do not seem to help for some other conditions people use them for such as gum infections, lupus, kidney or liver disease, or leg pain due to blood flow problems.
There isn't enough information to know if fish oils are effective for the other conditions people use them for, including: asthma, cancer, lung disease, hay fever, cystic fibrosis and many more.
- Lowering fats called triglycerides.
Likely Effective for...
- Preventing heart disease and heart attacks.
Possibly Effective for...
- High blood pressure.
- Heart failure.
- Reducing stiffness and pain related to rheumatoid arthritis.
- Menstrual pain (dysmenorrhea).
- Attention deficit-hyperactivity disorder (ADHD) in children.
- Abnormal sensitivity to cold (Raynaud's syndrome).
- Preventing stroke. Moderate fish consumption (once or twice a week) seems to lower stroke risk, but very high fish consumption might increase stroke risk.
- Osteoporosis, alone or in combination with calcium and evening primrose oil.
- Preventing hardening of the arteries (atherosclerosis).
- Preventing kidney problems.
- Bipolar disorder.
- Depression, when taken with conventional antidepressant medications.
- Weight loss.
- Endometrial cancer.
- Preventing eye disease (age-related maculopathy).
- Reducing the risk of blood vessel re-blockage after heart bypass surgery or "balloon" catheterization (balloon angioplasty).
- Preventing recurrent miscarriage in pregnant women with antiphospholipid syndrome.
- Preventing high blood pressure and kidney problems after heart transplant.
- Preventing damage to the kidneys and high blood pressure caused by taking a drug called cyclosporine.
- Improving movement disorders in children, in combination with evening primrose oil, thyme oil, and vitamin E (Efalex).
- Preventing blockage of grafts used in kidney dialysis. Psoriasis when used intravenously.
- Lowering cholesterol.
- Slowing weight loss in patients with advanced cancer.
- Asthma in children.
- Developmental coordination disorder.
- Dry eye syndrome.
Possibly Ineffective for...
- Gum infection (gingivitis).
- Liver disease.
- Leg pain due to blood flow problems (claudication).
- Preventing migraine headaches.
- Preventing muscle soreness caused by physical exercise.
- Breast pain.
- Skin rashes caused by allergic reactions.
- Stomach ulcers.
- Loss of appetite in people with advanced cancer.
Likely Ineffective for...
- Type 2 diabetes.
Insufficient Evidence to Rate Effectiveness for...
- Irregular heartbeat called ventricular arrhythmia; cataracts; lung disease; pneumonia; hayfever; cystic fibrosis; chronic fatigue syndrome; decreased kidney function; inflammatory bowel disease; Alzheimer's disease; complications during pregnancy; improving infant development; glaucoma; eczema in infants; schizophrenia; Lyme disease; systemic lupus erythematosus (an immune system disorder); "prediabetes," preventing cancers such as oral and pharyngeal cancer, esophageal cancer, colon cancer, rectal cancer, breast cancer, prostate cancer, and ovarian cancer; improving night vision in children with a disorder called dyslexia, and other conditions.
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).
Next: How does Fish Oil work?
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