Everyone is talking about Omega-3 fatty acids these days. They claim Omega-3s can help with heart and arterial health, improve mood, reduce inflammation and have other beneficial effects. Recent research has called some of this into question, but they are still considered both beneficial and commonly underconsumed, partly because foods that were once high in Omega-3s no longer are due to changes in farming practices.
What is commonly glossed over is that omega-3s are a family of fatty acids, the most important of which are alpha-linolenic acid (ALNA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). It is EPA and DHA that are especially important for health.
In most people, the body can synthesize EPA from ALNA and can synthesize DHA from EPA, but these processes are very inefficient. In other words, if you take in 100mg of ALNA, you’re likely to only convert that into about 5mg of EPA and less than 1mg of DHA.
This varies from person to person. It appears that in general women are much better at these conversions than men, presumably because of the need to provide DHA to the fetus. Men would do well to supplement with both EPA and DHA if possible.
The most common way to get EPA and DHA into the diet is to either eat wild-caught oily fish (farmed fish do not have high levels of omega-3s) or to supplement with fish oil capsules. These are cheap and effective and work for most people. The problem comes in when one doesn’t want to eat fish for ethical or health reasons.
Without going too much into those reasons, the ethical reasons usually are associated either not wanting to kill animals or with the environmental effects of overfishing. Many argue that fish oil is not a sustainable crop. The health concerns stem from the concentration of mercury and PCBs in fish.
The oils themselves come from algae in small concentrations and get more concentrated as you move up the food chain. This means that the fish higher up who are concentrating DHA and EPA in higher amounts are also concentrating mercury and PCBs in higher amounts. There are two solutions: either get fish oil capsules that have purified oil from which the contaminants have been removed or use vegetarian sources.
Until quite recently, the latter was not really an option, but there are now a handful of sources, though they tend to be much more expensive than fish sources. I struggled to find a reliable vegetarian source and when I first wrote this (2011), I still couldn’t reliably find one. Now (2015) it is easy to find vegetarian DHA and EPA supplements and the challenge is more going through the million options. I’ve settled on Deva Nutrition Deva Vegan DHA-EPA
Given the availability of the ingredients – algae and yeast that can be farmed – one might expect that the price of these will drop as the operations scale and the refining methods improve.
Meanwhile, one would hope that the cost of fish sources will rise given that we are fishing our oceans to death.
Sources
- Graham C. Burdge and Stephen A. Wootton, “Conversion of a-linolenic acid to eicosapentaenoic, docosapentaenoic and docosahexaenoic acids in young women,” British Journal of Nutrition (2002), 88: 411-420.
- Graham C. Burdge, Amanda E. Jones and Stephen A. Wootton, “Eicosapentaenoic and docosapentaenoic acids are the principal products of a-linolenic acid metabolism in young men,” British Journal of Nutrition (2002), 88: 355-363.