Omega-3 fatty acid is a type of essential fatty acid that humans immensely benefit from and also require for routine functioning. The human body doesn’t make this fat on its own, which means it has to depend on food for omega-3, and that makes omega-3 an “essential” fatty acid. Most plant and animal-based foods have some form of omega-3 fats in them. The lack of omega-3 acid in the body could cause fatigue, dry skin, poor memory, depression or mood swings, heart issues, and poor blood circulation. The human diet should therefore be rich in omega-3 fatty acid and also equivalently rich in omega-6 fatty acid, which is also an essential fatty acid.

Omega-3 fats provide the start to make hormones that control artery wall contraction and relaxation, blood clotting, and inflammation. Also, omega-3s attach to cell receptors and contribute in regulating genetic function. As a result, omega-3 fatty acid helps prevent stroke and heart disease, control lupus, rheumatoid arthritis and eczema, and could help protect against cancer and similar conditions.

Composition

Omega-3 fatty acid belongs to a broader fat group called polyunsaturated fat, which means it has more than one double bond (carbon-carbon). Like a typical fatty acid, omega-3 fat comprises chains of carbon, oxygen and hydrogen atoms. Every fatty acid has two ends: alpha (carboxylic acid end), which is the chain’s beginning; and omega (methyl end), which is considered the tail’s chain. These two ends are connected by some 18 to 22 carbon atoms. The number ‘3’ in omega-3 indicates that the initial double bond is situated at the third carbon when counted from the omega or methyl end.

Food Sources

Rich sources of omega-3 fat include flax seeds, chia seeds, fish and fish oil (salmon), seafood, and soybean and its derivatives (tempeh and tofu, for instance). Dark green veggies (spinach, collards, kale, and chard), walnuts, milk, and cereal grasses (barley and wheat grasses) are good sources as well. The chlorophyll-rich green foods have omega-3 fatty acids in their chloroplasts. Omega-3 supplements are also available, but they shouldn’t be your first choice. Also, some omega-3-rich foods such as nuts and oils could be calorie-dense. Therefore, eat them moderately if you don’t want to gain extra pounds.

As aforementioned, the human body needs both omega-3 and omega-6 fatty acid. But, American food has more omega-6 than omega-3 fat. Omega-3 reduces inflammation but omega-6 promotes inflammation. Too much inflammation could cause several health issues. It’s therefore important to balance out the two fatty acids. The Mediterranean diet strikes the right balance between omega-6 and omega-3 fatty acids. It usually comprises whole grains, fresh vegetables and fruits, olive oil, fish, garlic, and some wine.

Like humans and land animals, fishes don’t make their own omega-3s. Their omega-3 fats come from their diet, which includes sea plants, algae, etc. that are rich in omega-3. Fishes store this omega-3 fat in their tissue and these essential fats are inclusive of ALA, DHA, and EPA.

Like other nutrients, omega-3s in food are also susceptible to damage, which could be caused by heat, light or oxygen. This is why omega-3 fat-rich foods such as fish, eggs, dairy, and also seeds and nuts should be stored within sealed containers in a refrigerator. When chia or flax seeds are crushed to make them easier to chew or consume, their shelf life decreases, making it imperative to store them in opaque, sealed containers in a refrigerator.

Types

There are basically three types of omega-3 fatty acids:

  • Alpha-Linolenic Acid (ALA)

ALA is the most widely available omega-3 fat that has 18 carbons and three double bonds. It helps the body make necessary energy for the cells. Up to 85 percent of ALA derived from food gets broken down for the body’s energy requirements. The remaining 15 percent helps make the other two omega-3s on this list. Alpha-linolenic acid (ALA) is the simplest and the most common omega-3 fat available. It’s commonly found in nuts (particularly walnuts) and vegetable oils, leafy vegetables, flaxseed oil and flax seeds, soybean and canola oils, and fats of grass-fed animals. 

  • Eicosapentaenoic Acid (EPA)

Eicosapentaenoic acid has 20 carbons and five double bonds. EPA is responsible for making prostaglandins, a messaging molecule that’s responsible for the proper functioning of the inflammatory system. In fact, the majority of prostaglandins are courtesy EPA. There are some studies indicating EPA is more effective than DHA as far as reducing depression symptoms is concerned. EPA concentration is the most in fishes such as salmon, herring, shrimp, eel, and sturgeon.  

  • Docosahexaenoic Acid (DHA)

Docosahexaenoic acid is an omega-3 fat that contains 22 carbons and six double bonds. DHA ensures the proper functioning of the nervous system, which includes the brain. DHA, in fact, has a strong connection with brain function. The human brain is 60 percent fat by weight, with DHA making up approximately 15 to 20 percent of that fat. In other words, DHA is responsible for 9 to 12 percent of the total weight of the brain. DHA deficiencies have been linked with several issues, which includes neurodegenerative diseases such as Parkinson’s disease and cognitive issues such as the lack of reasoning ability in kids. EPA and DHA are also known as “marine omega-3s” as they primarily come from fish.

The above three are the primary omega-3 fatty acids. Some lesser known omega-3 fats are hexadecatrienoic acid, stearidonic acid, eicosatrienoic acid, docosapentaenoic acid, heneicosapentaenoic acid, tetracosahexaenoic acid, and eicosapentaenoic acid.

Conversion Process: ALA to EPA and DHA

EPA and DHA offer more health benefits than ALA, which is why animal-based omega-3 fats are considered superior to plant-based omega-3s. The body’s immune, cardiovascular, nervous, and inflammatory systems cannot properly function sans sufficient levels of DHA and EPA. When the circumstances are right, the human body can transform ALA into other forms of omega-3s with the help of a fatty acid enzyme called delta 6 desaturase. This means when the body doesn’t have sufficient ALA, it is likely to also be DHA and EPA-deficit. Unfortunately, this conversion isn’t quite efficient in humans. Usually, only 1 to 10 percent of ALA is transformed into EPA and 0.5 to 5 percent converted into DHA.  

The right circumstances for ALA conversion into DHA and EPA pertain to the other fat types consumed. Compared to omega-3s, the human body consumes more omega-6s, thanks to the latter’s presence being more plentiful in normal food compared to omega-3 fats. However, such high consumption of omega-6 fats could negatively impact the body’s ability to convert ALA into DHA and EPA, since omega-3s also want the same enzymes for their own conversion process. This competition could lead to lesser production of EPA. Similarly, the body cannot effectively convert ALA into DHA and EPA if there isn’t sufficient supply of specific nutrients such as vitamin B3, vitamin C, vitamin B6, and minerals such as magnesium and zinc.

Omega-3 Fatty Acid Benefits

  • Cognitive: The fatty acid is essential for memory and brain performance and also behavioral function. An infant who doesn’t get sufficient omega-3s from a mother during pregnancy could develop nerve and vision problems. Many studies suggest decreased omega-3 fat consumption is linked with dementia, which includes Alzheimer disease.
  • Vision: DHA is a big structural part of the eye’s retina, causing vision issues whenever there isn’t sufficient DHA. Getting sufficient omega-3 is linked with reduced macular degeneration risk, which is among the leading reasons why people go blind or incur severe damages to the eye.
  • Anti-inflammation: Omega-3 helps boost an anti-inflammatory drug’s effectiveness. Individuals suffering from inflammation-caused diseases such as asthma could see improvements in their condition with omega-3 consumption.
  • Lowers cholesterol: People who take increased levels of omega-3 fatty acid happen to have decreased triglycerides (blood fat) and increased HDL cholesterol (good cholesterol). This also helps with diabetes.
  • Lowers blood pressure: Individuals with hypertension may see omega-3 fat-rich diets lowering their blood pressure.
  • Cardiovascular benefit: The omega-3 fat in fish oil helps decrease the risk profile for heart disease, which includes high blood pressure and high cholesterol.
  • Osteoporosis: Some studies indicate omega-3 fat could help increase calcium levels in some people, thereby improving bone strength. A few studies also indicate bone loss is likely in people who are low on this essential fatty acid.
  • Skin disorders: A particular clinical study indicated people with photo dermatitis, a skin disorder relating to sun sensitivity, exhibited less vulnerability to the sun’s UV rays after administering fish oil supplements.
  • Anxiety/depression: According to some studies, regular consumption of omega-3 fats can decrease depression in people.
  • Other medical conditions: The other problems omega-3 fat could address at varying degrees are menstrual pain, colon cancer, breast cancer, prostate cancer, liver fat, sleep issues, and inflammatory bowel disease (IBD).

Like with every other food nutrient, omega-3 must be taken in moderation and shouldn’t be consumed with the sole objective to cure a medical or cosmetic problem. For example, consuming omega-3 fatty acids cannot replace your topical sunscreens. Also, not all sources of omega-3 fatty acids are equally potent or beneficial, for reasons aforementioned. For instance, the omega-3 from flaxseed and omega-3 from fish oil need not present the same benefits. An overflow of omega-3 in the body could, in fact, cause more harm than good. For instance, people having type 2 diabetes may notice a minor bump in their blood sugar levels when administering fish oil.