There are different types of omega-3s and some are more beneficial than others. The three essential omega-3s the body needs are ALA, EPA and DHA. Find out more about them and their health benefits below.
Omega-3s are polyunsaturated fats. These refer to fat molecules with double bonds (more than one unsaturated carbon bond). They play significant roles in the body, including managing inflammation and maintaining cognitive function and heart health.
Scientists have discovered 11 omega-3 fatty acids so far – and only three of them are important to the human body.
ALA is the most bountiful kind of omega-3 fatty acid. It is mostly acquired from plants, but the body cannot directly use it. The body needs to convert it first into EPA and DHA before it can be used. If not, it is used as a fuel or stored away like other fats.
Even though humans acquire a lot of ALA, only a small percentage of it used. The body cannot convert it efficiently. This conversion process deteriorates over time as a person ages.
The body needs EPA to produce signaling molecules called eicosanoids. These compounds are involved in regulating inflammation.
While acute inflammation is useful in fighting diseases, chronic, low-level inflammation contributes to several health conditions, such as obesity, cardiovascular disease and rheumatoid arthritis.
A person can acquire EPA from several kinds of seafood, but mostly in wild-caught salmon, eel and shrimp. Some concentrations can be found in grass-fed animal products as well, like dairy and meats.
While all three fatty acids are important, DHA is particularly beneficial. The omega-3s found in the brain and retina are mostly comprised of DHA – 97 percent and 50 percent, respectively. DHA is part of the structural component of the retina and the skin.
This particular fatty acid is vital for brain development and maintaining healthy cognitive function among adults. One study found that DHA deficiency may be linked to Alzheimer's disease and impaired brain function as a person ages.
DHA contributes to several other bodily processes, especially in the cardiovascular system. It can help lower blood triglycerides and potentially reduce levels of LDL or "bad" cholesterol. DHA has also been associated with helping treat arthritis, Type 2 diabetes and high blood pressure. (Related: Omega-3 fatty acid, DHA switches off cellular inflammation to slash chronic disease risk.)
Like EPA, high concentrations of DHA can be found in fresh seafood – like fatty fish and algae – and various seeds and nuts. People can also acquire small amounts from organic animal products.
The recommended daily amount of ALA depends on a person's age and sex. In general, it is recommended that men consume 1.6 g of ALA and 1.1 grams for women daily.
Aside from ALA, experts have not yet established recommended daily amounts for EPA and DHA. The US Food and Drug Administration, however, advises against consuming more than 3 g of EPA and DHA a day. Instead of improving a person's health, consuming too much may lead to potential adverse effects such as nausea and diarrhea.
Overall, adequate consumption of omega-3 fatty acids can help boost a person's health. Make sure to eat fresh foods rich in omega-3s and avoid excessive consumption.