If you have been following healthy nutrition as a topic for very long you have doubtless seen the back and forth between fish oil is good for you and fish oil doesn’t offer any benefit. It’s almost like the previous controversy about butter and margarine where there was back and forth for many years that finally resolved in butter’s favor.
Fish Oil and Purified Omega 3 fatty acids have a number of health benefits including:
Substantially lowering triglycerides and mildly elevating HDL cholesterol
Modestly lowering blood pressure
Improving mood
Decreasing inflammation
Despite the fact that high triglycerides, low HDL, inflammation, and blood pressure elevations are all substantial cardiovascular risk factors it has been difficult to prove in studies that people who take fish oil supplements have any lower cardiovascular risk. We know that eating fatty fish like salmon, mackerel, anchovies, sardines, and herring [SMASH Fish] regularly has improved cardiovascular risk. Some studies have shown benefit for overall cardiovascular health while others have not which has led to the on-balance assessment that benefit has not been proven.
COMPOSITION:
Omega 3 fatty acid supplements contain 2 main components - eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]. These most frequently come from fish oil and krill oil but they can be obtained to a lesser degree from the conversion of alphalinolenic acid [ALA] into omega-3 fatty acids in the body. Unfortunately, this conversion is not very efficient so obtaining significant amounts of EPA and DHA typically needs to come from fish or krill oil or from eating fish and other seafood in the diet.
The main effect of EPA is as an antiinflammatory agent. DHA on the other hand has a significant role serving as structural components of membranes in the brain and throughout the body. EPA has been used in its purified form as a prescription medication to lower triglycerides. DHA is often added to formula and now to milk with the thought that having sufficient quantities is important for growing children who are developing and remodeling their brain as they grow.
CARDIOVASCULAR AND LIPID EFFECTS:
One of the most demonstrable effects of omega 3 fatty acid supplementation in general and the administration of EPA is the lowering of triglycerides. Combined EPA/DHA supplements and Purified EPA supplementation has been shown to lower elevated triglycerides by up to 30% or more at a dose of 4 grams/day. Omega 3 supplements containing both EPA and DHA also lower triglycerides and also modestly raise HDL good cholesterol. Both elevated triglycerides and low HDL are significant components of metabolic syndrome which is associated with substantially increased risks of cardiovascular problems. Omega 3 fatty acid supplements also can modestly lower blood pressure. The change is only about 2.5 mm Systolic Blood Pressure decrease and 1.5 mm Diastolic Blood Pressure decrease. That seems like a small amount but every 1 mm. diastolic pressure reduction in the population lowers the risk of heart attack and stroke.
DECREASING INFLAMMATION:
Omega 3 fatty acid supplementation often improves conditions that are inflammatory in nature such as rheumatoid arthritis. Omega 3 supplementation has also shown promising results in other inflammatory conditions such as Inflammatory Bowel Disease [IBD] and asthma. Inflammation underlies a number of different major disease processes such as cardiovascular disease, cognitive decline, and cancer risk. Hence, lowering inflammation may have widespread benefits throughout the body.
MOOD IMPROVEMENT:
Omega 3 fatty acid supplementation has also been shown to improve mood in depression. Both unipolar and bipolar depression have improved when omega 3 fatty acid supplementation was initiated. Its effect seems to be most notable on individuals with major depression and it is less clear whether there is benefit with more minor degrees of depression. Again, as with lowering triglycerides it is the EPA that seems to have the most prominent effect. This could be due to its antiinflammatory effects as other anti-inflammatories such as curcumin have been shown to improve depression as well. Inflammation has been shown to be a factor in the response to antidepressant medications. It was noted that people with elevated hsCRP levels often respond better when two different classes of antidepressants are given, as response rates to a single SSRI agent are lower when there are markers of higher inflammatory levels.
FINAL THOUGHTS:
With all these benefits it is hard to pass up the benefits of increasing omega 3 fatty acids in your diet. The most effective strategies generally combine eating fatty fish and taking fish oil or krill supplements. The question of why the studies have been so mixed on the overall benefit of omega 3 supplements on cardiovascular outcomes remains an enigma, although some scholars have mused that ineffective low dosing in the studies was partially responsible. Personally, I think that a number of factors may come into play. Fish may have a wider spectrum of compounds such as beneficial Omega 7 and Omega 9 fatty acids in addition to Omega 3 fatty acids. It is also possible that lower quality fish oils have a higher degree of oxidation and hence the supplement may not provide as much protection as a fresher unoxidized product. This is one reason to stay with professional brands that use high quality raw material and do vigorous testing on an ongoing basis.
One final consideration is whether what else you eat in your diet makes a difference. It is possible that for omega 3 fatty acids to make a difference, they have to represent a certain percentage of fatty acids incorporated into your membranes and circulating in your blood stream. If you take a healthy omega 3 supplement and eat fish but this still represents a small percentage of the fats in your blood because your diet is too high in omega 6 oils and saturated fats then you may be washing out the benefits that omega 3 fatty acids can provide. The good news is that testing for healthy levels of omega 3 fatty acids is now commonly available, and give not only an informative baseline, but are an effective way to monitor how including more fish and omega 3 fatty acids in the diet improves your omega 3 index.
Comments