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Fish oil is a supplement with a proven track record of health benefits and little in the way of side effects.

If I were to recommend one single supplement, fish oil would be it. Fish oil is a fantastic source of omega-3 fatty acids which contain two active components, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which both appear to offer health benefits when given in combination.

What are the benefits of fish oil?

Helping improve lipids
Fish oil has a range of benefits, but one of the most effective is a reduction in blood lipids, particularly triglycerides. Doses of 2-3g daily have been shown to help reduce triglycerides and to help increase the levels of HDLs (high density lipids), the 鈥済ood fats鈥� in the blood. Fish oil has fewer side effects than other treatments for high triglycerides such as nicotinic acid.

Reduction of atherosclerosis
Supplementation with fish oil has demonstrated a reduction in the levels of atherosclerosis, the fatty plaques in arteries that can lead to blockages causing heart attacks. These effects are not limited to the heart鈥檚 arteries. Fish oil鈥檚 effects have also been demonstrated in the arteries of the neck where plaque development can lead to strokes.

While the studies are limited, evidence shows that fish oil supplementation can help stop the progression of plaques and even help reduce their size.

Blood pressure reduction
Whether it be from diet or via supplements, fish oil has been shown to help reduce blood pressure. While the effect is modest, it can be an effective treatment if blood pressure is only marginally raised.

Protection against sudden cardiac death
Perhaps one of the most powerful findings was that supplementing with doses as low as 500mg daily was enough to reduce the risk of sudden cardiac death and death by heart attack by 36 percent.

This was found to be similar protection whether or not the person had pre-existing cardiac disease. This is most likely due to helping reduce cardiac risk factors such as high blood pressure, and lipid and plaque reduction as mentioned above.

Reduction of depression
Studies have shown that mood improves with treatment with fish oil. In studies of children and adults with treatment-resistant depression, adding 1-3g of fish oil daily helped reduce symptoms of depression.
Studies show that people with manic depression also benefited from fish oil supplements, however, it was only effective for the depression symptoms and not for the manic symptoms.

For people with depression, adding fish oil can be a great start to treatment, but the effects are not as strong as formal treatments for depression. Including fish oil supplements with antidepressant treatments could be useful.

Does fish oil have side effects?
While there are many benefits to adding fish oil supplements, there are some potential side effects that are worth considering before adding these to your diet.
One study reported that fish oil can increase the risk of bleeding. Participants in this study were undergoing significant cardiac surgery and were receiving more than 6g of fish oil daily.

Other studies have shown that there was no increased risk of bleeding, concluding that as long as you are taking less then 6g daily there was little chance of bleeding.
There is anecdotal evidence of mildly increased bruising so if you are considering getting a tattoo or having Botox鈩� treatments, it may be worth stopping your supplements one week beforehand.

Some people find they have burp more after taking fish oil and the fishy taste can be unpleasant. Some recommend freezing the capsules or trying different brands to reduce the taste.

Initially there were concerns that there was a risk of heavy-metal exposure due to the way fish oil was extracted. Mercury has been found in many of the big fish such as shark, tuna and swordfish, however, almost all fish oil is now derived from smaller fish, reducing the risk of heavy-metal exposure to almost nil.

As with all supplements, there is a risk of interactions with other medications. If you are taking any medications or supplements, talk to your doctor before you add fish oil to your diet.

What is the best dose of fish oil to take?
After reviewing many of the studies, the following doses are their recommendations.
For depression: One gram daily was used in these studies and showed good effect on lifting mood.

Other studies of depression have used doses up to 12g daily, however, these were patients admitted to hospital due to their extreme depression.
For blood pressure reduction: 3g daily appears to have the best response for reducing blood pressure. Doses higher than this did not appear to have more effect.

For reduction of triglycerides: To gain the benefit of reducing triglycerides and also increasing HDL (the good fats in the blood), doses of at least 3g daily are needed. Doses lower then this appear to have little effect.
For heart protection: Doses as low as 500mg daily have been shown to be cardiac protective, however, in most of the studies, people were taking at least 1g of fish oil daily.
Can you overdose on fish oil? Studies have shown that people taking up to 12g of fish oil daily did not have adverse effects. That said, the current recommendations for taking fish oil are around 1-3g daily.

If you prefer to go direct to the source: People not living with heart disease can get their recommended dose of fish oil via one – two meals of oily fish on a weekly basis. The fish with the highest content of omega-3 fatty acids are anchovies, salmon and sardines. If you are not keen on regular fish meals, 1-3g of fish oil daily is recommended.

By DR GEORGE FORGAN-SMITH
General Practitioner

An excerpt from