Where it comes from: Fish oil contains omega-3 fatty acids and is derived from the tissues of fatty, cold-water ocean fish such as tuna, cod liver and salmon. It was first used during the late 1700s in fishing communities surrounding the Northern Atlantic Ocean to treat infections and sickness. In those times, patients would simply eat cod liver soaked between two pieces of bread. In the 1800s, a steaming process was developed, making the pungent taste (read: disgusting) slightly more bearable. Today, the oil is manufactured into pill form, offering a much more pleasant way to ingest a dosage.
What it'll do for you: The list of benefits is plentiful. In fact, the National Institute of Health lists fish oil and other omega-3 fatty acids as being helpful in treating or preventing 37 conditions. Here, some of the most noteworthy:
- Promotes heart health
Researchers at the Harvard School of Public Health calculated that eating about two grams per week of omega-3 fatty acids (equal to one or two servings of fatty fish) reduces the chances of dying from heart disease by more than one-third. Omega-3 fats protect the heart against the development of erratic cardiac rhythm disturbances, help break up blood clots and lower cholesterol, tryglicerides, LDLs and blood pressure. The fats also increase good HDL cholesterol.
- Protects against cancer
Studies have found that fish oil can help prevent three of the most common forms of cancer: breast, colon and prostate. The fatty acids stop the alteration of a normal healthy cell to that of a cancerous mass and cause the death of some cancer cells. Researchers are currently digging deeper to see how fish oil can play a larger role in cancer survival and prevention.
- Improves mental health
Researchers at the University of Sheffield have found that fish oil supplements can alleviate the symptoms of depression, schizophrenia and bipolar disorders. On a seemingly related note, a Chinese study of 100 suicide-attempt cases found diets low in fishy meals to be a common factor. Other studies report that depressed patients who take omega-3 fatty acids in addition to prescription antidepressants had a great improvement in symptoms than those who took antidepressants alone.
- Helps prevent degenerative disorders
Researchers at LSU Health Sciences Center New Orleans found the presence of omega three fatty acids in the diet prevent proteins from misfolding and forming a gene mutation in degenerative diseases like Parkinson's and Huntington's. Other recent studies have shown that people who eat a lot of fatty fish score better on memory tests and are less likely to develop Alzheimer's disease.
- Relieves pain and fight arthritis
There have been many studies reporting improvements in morning stiffness and joint tenderness with the regular intake of fish oil supplements for up to three months. One study performed at Albany Medical College even suggests that people with rheumatoid arthritis who take fish oil may be able to lower their dose of non-steroidal anti-inflammatory drugs.
- Improves IQ Alzheimer's and Parkinson's patients aren't the only ones to get a memory boost from fish oil and omega-3 fatty acids. A 2009 study of healthy adults—55 and older—found that those who took a fatty acid supplement for six months had almost double the reduction in errors on a test that measured learning and memory skills compared to those who took a placebo.
Suggested intake: The U.S. Food and Drug Administration classifies the intake of up to three grams per day of omega-3 fatty acids from fish in the "Generally Regarded as Safe" category. With that in mind, the American Heart Association recommends eating fish two times a week.
"Omega-3 fatty acids are best sourced through food," says registered dietitian and American Dietetic Association spokesperson Jim White. "Evidence is stronger for the benefits of eating fish rich in omega-3 fatty acids compared with using supplements."
White—and experts across the board—suggests fishy meals of salmon, mackerel, cod, trout and tuna, as they're high in omega-3s while they also have low levels of mercury content. Other dietary sources of omega-3 fatty acids include flaxseed, canola oil, soybeans, pumpkin seeds and walnuts.
Those who opt for fish oil supplements over (or in addition to) servings of seafood, should discus the issue with a doctor, as a different amount of fish oil is prescribed for different health conditions.
Name-brand vs. generic: There are countless brands of fish oil supplements on the market, ranging in prices from $5 to more than $30 but White says there are a few things more important than price to look for:
"The bottle must list the specific species of fish used to make the oil—again, salmon, tuna, sardines and anchovies are the riches sources. It must expressively say it contains omega-3 fatty acids; not just 'fish oil.'"
The label should also list the total amount of EPA and DHA, and the list should add up to the total amount of oils in the product. "If they don't, you're buying a bunch of fillers," warns White. Check the bottle for a marking indicating that it's been health screened and disease-free. The bottle may list where the fish came from and should offer a guarantee to be 100 percent pure, meaning there are no toxins, heavy metals or pesticides.
Associated risks: According to the NIH, high doses (more than three grams per day) of omega-3 fatty acids may increase the risk of bleeding. Some species of fish (such as tuna) carry a higher risk of environmental contamination such as methylmercury poisoning—also what Jeremy Piven claimed to have had to get out of his Broadway appearances two years ago. "Fish oil may reduce the immune system's activity, reducing the body's ability to fight infection and increase levels of the bad LDL cholesterol," warns White. "Ironically, taking massive amounts of fish oil can actually increase the risk of stroke."
Be sure to discuss with all prescribing doctors before you begin taking supplements.
Latest news: Fish oil made headlines recently when a group of environmentalists in California filed a lawsuit against popular brands of supplements. The claim says the pills contain unsafe and illegal levels of the carcinogenic chemicals (PCBs, which White cautioned against at the top of this page).
The lawsuit names eight manufacturers or distributors—including CVS Pharmacy and Rite Aid—for alleged violations of California's Proposition 65, which requires that consumers be warned about chemical exposures.