The 3 Most Important Types of Omega-3 Fatty Acids
By Freydis Hjalmarsdottir, MS
Omega-3 fatty acids are essential fats that have numerous health benefits.
However, not all omega-3s are created equal. Among 11 types, the 3 most important are ALA, EPA, and DHA.
ALA is mostly found in plants, while EPA and DHA are mostly found in animal foods like fatty fish.
This article takes a detailed look at the 3 most important types of omega-3s.
What Are Omega-3 Fatty Acids?
Omega-3s are a type of polyunsaturated fat. They're deemed essential fatty acids because they're necessary for health but cannot be made by your body.
Thus, you must get them from your diet.
Rather than being stored and used for energy, they play important roles in many bodily processes, including inflammation, heart health, and brain function.
Omega-3 fatty acids are a group of polyunsaturated fats that you must get from your diet. They have numerous health benefits.
1. ALA (Alpha-Linolenic Acid)
Alpha-linolenic acid (ALA) is the most common omega-3 fatty acid in your diet.
It's mostly found in plant foods and needs to be converted into EPA or DHA before it can be utilized by your body for something other than energy.
However, this conversion process is inefficient in humans. Only a small percentage of ALA is converted into EPA — and even less into DHA (3Trusted Source, 4Trusted Source, 5Trusted Source, 6Trusted Source).
When ALA is not converted to EPA or DHA, it is simply stored or used as energy like other fats.
Some observational studies link a diet rich in ALA to a reduced risk of death from heart disease, while others show an increased risk of prostate cancer (7Trusted Source).
This increase in prostate cancer risk was not associated with the other main omega-3 types, EPA and DHA, which seem to protect against this cancer (8Trusted Source).
Some seed oils, such as flaxseed and rapeseed (canola) oil, are also high in ALA.
ALA is mostly found in plant foods. Your body can convert it into EPA or DHA, though this process is highly inefficient.
2. EPA (Eicosapentaenoic Acid)
Your body uses eicosapentaenoic acid (EPA) to produce signaling molecules called eicosanoids, which play numerous physiological roles and reduce inflammation (9Trusted Source).
Chronic, low-level inflammation is known to drive several common diseases (10Trusted Source).
Various studies indicate that fish oil, which is high in EPA and DHA, may reduce symptoms of depression. Some evidence suggests that EPA is superior to DHA in this regard (11Trusted Source, 12Trusted Source).
One study in menopausal women noted that EPA reduced their number of hot flashes (13Trusted Source).
Both EPA and DHA are mostly found in seafood, including fatty fish and algae. For this reason, they are often called marine omega-3s.
EPA concentrations are highest in herring, salmon, eel, shrimp, and sturgeon. Grass-fed animal products, such as dairy and meats, also contain some EPA.
EPA is an omega-3 fatty acid that can reduce symptoms of depression and help fight inflammation in your body.
3. DHA (Docosahexaenoic Acid)
Docosahexaenoic acid (DHA) is an important structural component of your skin and the retinas in your eyes (14).
Fortifying baby formula with DHA leads to improved vision in infants (15Trusted Source).
DHA is vital for brain development and function in childhood, as well as brain function in adults.
Early-life DHA deficiency is associated with problems later on, such as learning disabilities, ADHD, and aggressive hostility (16Trusted Source).
A decrease in DHA in later life is also linked to impaired brain function and the onset of Alzheimer's disease (17Trusted Source).
As mentioned above, DHA is found in high amounts in seafood, including fatty fish and algae. Grass-fed animal products also contain some DHA.
DHA is very important for brain development and may protect against heart disease, cancer, and other health problems.
ALA, the most common omega-3 fat, is not biologically active until it's converted into EPA or DHA, which are essential for your body (3Trusted Source).
However, this conversion process is inefficient in humans. On average, only 1–10% of ALA is converted into EPA and 0.5–5% into DHA (4Trusted Source, 5Trusted Source, 6Trusted Source, 22Trusted Source).
Furthermore, the conversion rate depends on adequate levels of other nutrients, such as copper, calcium, magnesium, zinc, iron, and vitamins B6 and B7. The modern diet, especially vegetarianism, lacks some of these (23Trusted Source).
In addition, some omega-6 fatty acids compete for the same enzymes needed for this process. Therefore, the high amount of omega-6 in the modern diet may reduce the conversion of ALA to EPA and DHA (5Trusted Source, 24Trusted Source).
Other than being used for energy, ALA is not biologically active in your body. It needs to be turned into EPA and/or DHA to become active, but this conversion process is inefficient in humans.
8 Other Omega-3 Fatty Acids
ALA, EPA, and DHA are the most abundant omega-3 fatty acids in your diet.
However, at least eight other omega-3 fatty acids have been discovered:
- hexadecatrienoic acid (HTA)
- stearidonic acid (SDA)
- eicosatrienoic acid (ETE)
- eicosatetraenoic acid (ETA)
- heneicosapentaenoic acid (HPA)
- docosapentaenoic acid (DPA)
- tetracosapentaenoic acid
- tetracosahexaenoic acid
These fatty acids occur in some foods but are not considered essential. Yet, some of them do have biological effects.
At least eight other omega-3 fatty acids have been discovered. They're found in some foods and may have biological effects.
Which Omega-3 Fatty Acid is Best?
The most important omega-3s are EPA and DHA.
They're mainly found in seafood, including fatty fish and algae, meat and dairy from grass-fed animals, and omega-3-enriched or pastured eggs.
If you don't eat a lot of these foods, you may want to consider supplements.
EPA and DHA are generally considered the most important omega-3 fatty acids.
The Bottom Line
Omega-3 fatty acids are essential to maintain good health.
The most important types are EPA and DHA, which are abundant in fish oil, fatty fish, and many other seafoods. Algal oil is a good option for vegetarians and vegans.
Notably, EPA and DHA can also be formed from ALA, which exists in certain high-fat plant foods, such as flax seeds, flaxseed oil, walnuts, and chia seeds.
If you are eating inadequate amounts of omega-3-rich foods, supplements are generally recommended. You can easily buy them in stores or online.
Reposted with permission from our media associate Healthline.
EcoWatch Daily Newsletter
As protests are taking place across our nation in response to the killing of George Floyd, we want to acknowledge the importance of this protest and the Black Lives Matter movement. Over the years, we've aimed to be sensitive and prioritize stories that highlight the intersection between racial and environmental injustice. From our years of covering the environment, we know that too often marginalized communities around the world are disproportionately affected by environmental crises.
- Lead Poisoning Reveals Environmental Racism in the US - EcoWatch ›
- First-of-Its-Kind Study Finds Racial Gap Between Who Causes Air ... ›
- Pollution, Race and the Search for Justice - EcoWatch ›
By Peter Beech
Using waste food to farm insects as fish food and high-tech real-time water quality monitoring: innovations that could help change global aquaculture, were showcased at the World Economic Forum's Virtual Ocean Dialogues 2020.
Fly fishing. nextProtein
BiOceanOr's AquaREAL system. BiOceanOr
- Environmental Innovation Will Transform Business as Usual ... ›
- How an Army of Ocean Farmers Is Starting an Economic Revolution ... ›
The big three broadcast channels failed to cover the disproportionate impacts of extreme weather on low-income communities or communities of color during their primetime coverage of seven hurricanes and one tropical storm over three years, a Media Matters for America analysis revealed.
Researchers at the pharmaceutical giant Eli Lilly announced yesterday that it will start a trial on a new drug designed specifically for COVID-19, a milestone in the race to stop the infectious disease, according to STAT News.
- Dogs Can Smell COVID-19 - EcoWatch ›
- Drugs Touted by Trump for COVID-19 Increase Heart Risks, Studies ... ›
- Coronavirus Vaccine Candidate Shows Promise in Mice - EcoWatch ›
The sixth mass extinction is here, and it's speeding up.
Terrestrial vertebrates on the brink (i.e., with 1,000 or fewer individuals) include species such as (A) Sumatran rhino (Dicerorhinus sumatrensis; image credit: Rhett A. Butler [photographer]), (B) Clarion island wren (Troglodytes tanneri; image credit: Claudio Contreras Koob [photographer]), (C) Española Giant Tortoise (Chelonoidis hoodensis; image credit: G.C.), and (D) Harlequin frog (Atelopus varius; the population size of the species is unknown but it is estimated at less than 1,000; image credit: G.C.).
- Humanity 'Sleepwalking Towards the Edge of a Cliff': 60% of Earth's ... ›
- New Border Wall Construction Threatens 8 Species With Extinction ... ›
- The Insect Apocalypse Is Coming: Here Are 5 Lessons We Must Learn ›
By Cathy Cassata
With more than 1.7 million confirmed cases of COVID-19 in the United States and more than 100,000 deaths from the virus, physicians face unprecedented challenges in their efforts to keep Americans safe.
They also encounter what some call an "infodemic," an outbreak of misinformation that's making it more difficult to treat patients.
When Leaders and Doctors Spread Misinformation<p>When people in charge of towns, cities, states, and countries spread misinformation, the potential for belief in misinformation to result in policies can have harmful effects.</p><p><a href="https://www.northwell.edu/find-care/find-a-doctor?q=Bruce+E.+Hirsch%2C+MD&insurance=&location=&query_type=provider&physician_partners=false&default_view=list&gender=&language=&sort=relevancy" target="_blank">Dr. Bruce E. Hirsch</a>, attending physician and assistant professor in the infectious disease division of Northwell Health in Manhasset, New York, says an example of this is when President Trump informed the public he was taking hydroxychloroquine as a preventive measure.</p><p>"To approach this enormous challenge, we need some intellectual honesty and clarity, and to disregard expertise and to make decisions and model decisions based on hunches is inviting us to handle challenges on the basis of rumor and uninformed opinion. The magnitude of that error is epic," Hirsch told Healthline.</p><p>Stukus agrees, noting that the harm of this proclamation is documented.</p><p>"Early on when the president touted the benefits of hydroxychloroquine and azithromycin, people started to hoard this medicine, and state boards had to shut it down because they were getting so many prescriptions for this unproven therapy that it was not available for those who truly needed it, such as those who have lupus and autoimmune conditions," Stukus said.</p><p>He adds that calls to poison control centers increased after the president suggested using disinfectant to prevent contracting the new coronavirus.</p>
Listen to Science, Even When it Changes<p>When recommendations change or evidence flip-flops, skepticism may arise. However, Stukus says change is the beauty of science.</p><p>"That shows us that we can evolve, and if the evidence shows that our prior thoughts were incorrect, we need to be able to change our recommendations and advice based upon the best quality of evidence at the time," he said.</p><p>Pierre agrees.</p><p>"Science is an iterative process, whereby we arrive at facts and truth through repeated and controlled observations. That means that it's inherently self-correcting as we revise conclusions based on ongoing research. Scientific facts aren't immutable dogma chiseled on a tablet. They change based on the best available evidence we have at a given point in time," he said.</p><p>Because research of COVID-19 has only been underway for 6 months, information is evolving rapidly, and new information may contradict old.</p><p>"There's still much we don't know about exactly how [COVID-19] spreads, what effects it has on the body, or how to best treat it. That means that the best available evidence is preliminary, but that doesn't mean that we should ignore it or turn to other sources of information or opinion as if they're just as valid," Pierre said.</p><p>He explains that conspiracy theories based on mistrust lead to vulnerability to misinformation.</p><p>If people mistrust science because it sometimes "changes its mind," Pierre said, "that shouldn't be used to embrace other opinions based on no evidence at all, which are typically selected based on confirmation bias: what we want to believe rather than what the objective evidence supports."</p>
Where to Find the Best Information<p>Stukus says to start with the <a href="https://www.cdc.gov/coronavirus/2019-nCoV/index.html" target="_blank">CDC</a> and <a href="https://www.nih.gov/health-information/coronavirus" target="_blank">NIH</a>. Then check with your local health officials, because COVID-19 guidelines may vary depending on where you live.</p><p>If you can't find information you need or have questions specifically related to you, call your primary care doctor.</p><p>"Your personal doctor should always be a resource for individual specific questions because they know best how to apply all the nuances retaining to your health, and how to incorporate all the other general [COVID-19] recommendations," Stukus said.</p><p><a href="https://www.eehealth.org/find-a-doctor/b/boyd-laura-b/" target="_blank">Dr. Laura Boyd</a>, primary care physician at Edward-Elmhurst Health Center in Elmhurst, Illinois, says her clinic receives a lot of calls about COVID-19.</p><p>"Most doctors' offices are receiving calls and answering questions, and doing phone or video visits to help clarify and/or order testing over the phone based on patients' symptoms. It is always best to call your doctor's office first instead of worrying about symptoms and waiting too long to seek treatment," she told Healthline.</p><p>If your primary care doctor has limited testing, she suggests looking on your state's public health website for available testing sites.</p><p>With a lot of unknowns related to this virus and disease, Boyd says many patients are feeling overwhelmed and anxious for a treatment.</p><p>"Unfortunately, there is no specific medication recommended for COVID for outpatient. There are a lot of ongoing studies with various drugs going on within the hospital setting. Patients should always contact their doctors about their specific symptoms as they can treat the symptoms that go along with COVID, but there is no cure," Boyd said.</p><p>While we wait for treatment and a vaccine, Hirsch, who treats patients hospitalized for COVID-19 complications on a daily basis, says everyone can do their part by washing hands, wearing a mask, and staying 6 feet apart.</p><p>"As an infectious disease doctor working in the hospital, I see the damage of the pandemic and the worst cases of what's happening. We are trying to get the best possible outcome and confronting this overwhelming biologic reality of this terrible epidemic the best we can," Hirsch said.</p><p>Everyone at home can help in the fight too, he adds.</p><p>"Follow information that is science- and evidence-based, and avoid that which is not," he said.</p>
- WHO Declares Global Health Emergency as Coronavirus Cases ... ›
- Here's What We Know About Ibuprofen and COVID-19 - EcoWatch ›
- Trump's Budget Plan: A Push for Even Greater Environmental ... ›
- Trump Pushed for Mining Project That Could Destroy Alaska Salmon ... ›