There are a few main vegetarian DHA sources available on the market. Two of the most common are algae and fungus, which people usually ingest in supplement form. People also can get DHA from some vegetable oils. Nuts and some green vegetables such as Brussel sprouts are additional alternatives.
DHA is an omega-3 fatty acid that is strongly linked to cell and brain function. It appears in the cell mitochondria, structures that produce energy. The fatty acid also allows signals to pass easily from one brain cell to another. Without DHA, brain function and overall health suffers. It is for this reason that vegetarians cannot exclude it from their diet.
Women who are pregnant or nursing need to be especially careful to get enough DHA in their diet. The fatty acid is critical to the brain development of the baby. It also is very important in the development of the baby's eyes.
The most common vegetarian DHA source is algae. Fish are rich in DHA largely because they eat these organisms. Many people eat algae "raw," meaning they consume it as a whole food, such as adding dried algae to a smoothie. Different types of algae are also available as supplements, either as pills, capsules or liquid drops.
Recently, the use of algae as a vegetarian DHA supplement has been called into question. The problem occurs when manufacturers process the algae using hexane extraction, combining it with certain acids or, in some cases, bleach. In the United States, companies often add algae processed in this way to infant formulas and, more recently, to animal products like milk and yogurt. Some children, especially young babies, have experienced some gastrointestinal upset, including diarrhea. This can be very serious for infants, so algae-based supplements should be used with caution.
Even when algae is processed safely, it is still considered an inferior DHA source compared to fish. The body has to tweak the DHA in algae slightly to get it into a form that it can use readily. The DHA in fish, by contrast, is already in a form that the body can accept.
Advocates of getting DHA from algae often suggest that it is free from contaminants such as mercury, making it a healthier way to get DHA than eating fish. This is not true. Contamination usually starts at the bottom of the food chain, meaning that algae are just as susceptible to becoming too toxic to ingest. People who want to eat algae raw or as supplements therefore have to be careful about where the algae was grown.
Sometimes fungi can also be used as vegetarian DHA sources just like algae. They also come in pill form. A vegetarian can purchase fungi-based DHA supplements from health food stores or online retailers. A concern with these products, however, is that some individuals are allergic to certain fungi. Individuals who have mold allergies should avoid this option.
Foods Containing ALA
Alpha-linolenic acid, better known as ALA, is an omega-3 fatty acid similar to DHA. The main difference is that ALA is found in plants. It is associated with brain health and is also thought to benefit the heart and immune system. ALA is important for vegetarians seeking DHA because the body can convert ALA to DHA, although the process can be inefficient.
ALA appears in several fatty vegetable oils, including canola and soybean oils. Flax seed and flax seed oil, however, is the leading source of ALA. An easy way to incorporate it in the diet is to sprinkle some on salads.
Nuts are another ALA source. In particular, walnuts are rich in this omega-3 fatty acid. It's best to eat them raw, but they also can be eaten baked into or sprinkled on breads and muffins. Some people enjoy blending them into nut-based smoothies for an alternative to a fruity drink.
If vegetable oils and nuts don't appeal, a person can turn to some green vegetables to get their ALA. Spinach and kale are two nutrient-rich options. Brussel sprouts work, as well.
As with any supplement, consumers who do not consume animal products are advised to seek the advice of a pharmacist, doctor, or registered dietitian before taking vegetarian DHA sources in supplement form. These professionals can ensure that proper fatty acids and other important nutrients are being consumed through a combination of foods, drinks and supplements. They also help clients get the supplements that are right for their unique physiology and circumstances.