A Guide to Evaluating ALA as a Vegetarian Source of Omega-3
Alpha-Linoleic Acid – better known as (ALA) – is one type of omega-3 essential fatty acid. It is considered “essential” because your body cannot produce it on its own, and thus has to obtain it through dietary means in order to function properly. Foods that are rich in sources of ALA include:
- Flaxseed oil
- Chia seeds
- Leafy greens
Because ALA is derived primarily from plant sources, this type of omega-3 is often considered the best for vegetarians.
The argument that flax-seed oil is the best source of omega-3s for vegetarians is not entirely logically convincing, since it ignores certain crucial assumptions.
To better understand this, it’s helpful to know that there are two types of omega-3 fatty acids. There are short chain and long chain, and these titles refer to the length of the carbon chain on each acid. The long chain types, EPA and DHA have 20 and 22 carbons, respectively. ALA on the other hand, is a short chain and contains only 18 carbons.
ALA is Inferior to EPA & DHA
First, the argument assumes that your body can efficiently make use of ALA. Instead, your body merely *uses* ALA to produce EPA and DHA (the two other essential fatty acids in omega-3s). However, this process is not very efficient. In fact, the study with the most liberal results to date indicates that only 15% of ALA gets converted into the more useful EPA & DHA, while another study reported a conversion rate of only 0.2%. So while the ALA found in flax-seed oil is one source of omega-3s, not all of it is converted into a form that your body can make use of.
ALA Increases Inflammation
Second, the argument never addresses what happens to the ALA that doesn’t get converted into EPA and DHA. For instance, if we average the total percentage of ALA in a usable form, we get something like 8%. The remaining 92% that doesn’t get converted instead gets converted into Arachidonic Acid (AA), which is responsible for increased inflammation in the body – the very inflammation that the omega-3s are taken to mitigate!
ALA has been Linked to Cancer & Vision Problems
Finally, the argument omits the correlation between ALA, certain types of cancer, and an increased risk for age related macular degeneration (AMD). While there have been numerous studies and clinical trials showing a strong correlation between higher levels of EPA & DHA and lower risk of developing cancer and AMD, some studies actually show that diets high in ALA may lead to an *increased* risk for these conditions. You can read more about omega-3 fish oil and cancer in some of my earlier posts.
Thus, the argument is not completely sound. The evidence in support of the conclusion that flax-seed oil is the best source of omega-3s for vegetarians does little to prove the conclusion since it does not address the assumptions already raised. Ultimately, the argument might be strengthened if the vegetarian source of omega-3 was superior to EPA & DHA sources, did not increase inflammation within the body, and was not associated with harmful side effects. At the very least, flax-seed oil is a highly inefficient source of omega-3s, and at worst, it can actually exacerbate inflammation-based conditions. If you are a vegetarian, consider making a compromise – after all, we wouldn’t be human without the omega-3s from fish oil.
Other Vegetarian Sources of Omega-3s
Since Omega-3s aren’t actually created by fish, and instead come from the micro-algae that is the primary food source for marine life, in theory we should be able to create omega-3 supplements from that algae. However, this has proven to be a difficult and expensive task. There is a product called V-Pure Omega 3 Vegetarian EPA & DHA, but it’s expensive, low- concentration and only has 25mg of EPA per capsule. While it has a lot to be desired, being made from pure algae makes it a true vegetarian source of Omega-3. An alternative brand is Martek, but their products only contain DHA and not EPA.