Omega-3 fats are incredibly beneficial for health. The most important are:
ALA is an 'essential' omega-3 fatty acid found in plant foods and necessary for good health. However, only a small proportion of ALA converts into EPA and DHA, which also have a wealth of health benefits.
The most absorbable form of EPA and DHA comes from oily fish, including salmon, mackerel, anchovies, sardines and herring. Fatty fish also provide some vitamin D, a range of other vitamins and minerals and healthy protein.
For adequate amounts of EPA and DHA, eating two portions of sustainable, oily fish a week is recommended. Of course, you'll also benefit from all the other nutrients that fish has to offer.
It's best to avoid fish heavy in mercury like shark, marlin, swordfish and tuna.
However, not everyone regularly eats oily fish – and many people choose to take daily fish oil or omega-3 supplementation instead...
Fish Oil Benefits: 14 Reasons to Consider Regular Intake
1. Anti-inflammatory effects
Numerous researchers believe that low-grade chronic inflammation underlies many diseases.
Several factors contribute to low-grade inflammation, including exposure to environmental toxins, including air pollution, smoking, poor diet, chronic stress, and obesity.
Long-term inflammation can damage healthy cells, tissues and organs, leading to premature ageing, chronic conditions and diseases including arthritis, cardiovascular disease, diabetes, autoimmune disorders and cancer.
Omega-3 fats are highly beneficial for our health with potent anti-inflammatory properties.
Nutritionally, we need a healthy balance of omega-3 to omega-6 fats. Sadly, the typical Western diet is high in omega-6 and low in omega-3 fats, which encourages chronic low-grade inflammation.
It’s essential to increase our omega-3 intake, and fish oils, in particular, can reduce inflammatory markers and oxidative stress.
2. May protect heart health, reduce cardiovascular disease risk
Fish eaters appear to have a lower rate of cardiovascular disease. The most recent meta-analysis of fish consumption found that the higher the fish intake, the lower the risk of fatal coronary heart disease (up to 13%).
Some research shows that supplementing with fish oils can reduce heart disease risk factors, including lowering high triglyceride levels and LDL cholesterol.
It may also help those with high blood pressure and vascular inflammation, decreasing the risk of arterial plaques.
Fish oils may protect against blood clots and those at high risk of arrhythmia and potential heart attack. Other research shows they may improve the survival rate of those who’ve suffered a heart attack.
3. Good for your brain
Omega-3 fats are necessary for normal brain development. During pregnancy and lactation, it’s beneficial to consume DHA for fetal brain development.
Some experts are concerned about the amount of mercury in fish and its potentially harmful effects on a developing brain. On balance, most agree that the benefits far outweigh the risks, but avoid fish high in mercury.
Research is mixed, but several positive studies show fatty fish consumption protects brain function and helps to delay cognitive decline.
Oily fish may also improve cognitive function in the elderly.
The higher the intake, the better it gets. One study found the maximum effect at 75g of fish per day.
One hospital study found that fish oil supplements slowed cognitive decline and brain shrinkage in elderly patients with normal cognition.
A small study gave fish oils to patients with varying degrees of cognitive impairment for 4 to 17 months. The fish oils reduced inflammation in the brain of those with mild cognitive impairment, and their symptoms improved.
Some evidence also suggests that higher DHA intake and increased DHA blood levels are linked to a reduced risk of dementia and Alzheimer’s disease.
Inflammation is associated with Alzheimer’s and Parkinson’s. Due to its power to increase pro-resolution molecules in the brain, reducing inflammation, DHA consumption could help to lower the rates of neurological diseases like these.
4. May reduce diabetes risk
Chronic inflammation and increased oxidative stress are associated with increased diabetes risk. The anti-inflammatory action of fish oils may help to reduce this.
Patients with type 2 diabetes could develop complications like cognitive impairment, dementia, and eye problems like diabetic retinopathy.
According to one animal study, fish oils may reduce oxidative stress in the brain and decrease the risk of cognitive decline in diabetics.
Another six-year observational study tracked the fish oil consumption of over 3,000 type 2 diabetic men and women between 55 and 80.
Those who met the target of 500mg of fish oil per day, or two portions of oily fish a week, were 48% less likely to develop diabetic retinopathy.
5. May aid weight loss
Obesity is linked to increased inflammation and a greater risk of chronic disease, including heart disease, diabetes and cancer. It appears that those who eat more fish have a lower risk of obesity.
Not all studies agree that omega-3 fatty acids aid weight loss, but several show positive results.
Some research shows that fish oils may improve body composition, and this might be due to a shift in metabolism that uses fuel for energy rather than storage.
A 2007 study demonstrated that fish oil supplements combined with regular exercise could improve metabolic and cardiovascular health and aid weight loss.
Other researchers carrying out a small study found that dietary fish oils decreased body fat.
In one meta-analysis of 21 studies, researchers concluded that fish oils might help to reduce abdominal fat, particularly when combined with other lifestyle changes.
Population studies are inconclusive as to whether fish consumption can protect against cancer.
While they suggest that there may be some protection against colorectal cancer, there could be other contributing lifestyle factors such as lower meat intake in fish eaters or a generally healthier lifestyle.
That said, some research does support the idea that fish oils can reduce the risk of some cancers, and there needs to be more analysis to reach a more conclusive answer.
Low-grade chronic inflammation and cancer are linked, so, arguably, fish oils can protect against this disease due to their anti-inflammatory, immunomodulatory action.
A high omega-6 to omega-3 ratio from the Western diet may also contribute to cancer, so increasing omega-3 intake to balance this out could be beneficial.
According to some research, women with previously diagnosed and treated early-stage breast cancer with higher EPA and DHA levels from fish oils have a 25% less chance of further complications than those with less intake.
A scientific review published in 2014 also found that EPA, DHA and ALA can inhibit breast tumour growth in women with breast cancer.
Omega-3 fats also have the potential to decrease the risk of prostate cancer and slow its progression. In a 2011 study, men who took fish oils showed decreased cancer proliferation.
7. Improves mental health, protects against depression and anxiety
The brain is the fattiest organ at around 60% fat, so eating omega-3 fats is essential for balancing moods.
Healthy omega-3 fats, particularly the EPA and DHA found in oily fish, are critical for the development and function of the central nervous system and brain.
Often, people with depression have lower omega-3 levels, which may contribute to mood disorders.
While evidence of the antidepressant effects of fish oils is conflicted, some studies support their use for relieving depression symptoms, particularly fish oil supplements with higher EPA.
Currently, research is limited. Some researchers believe that further investigation is warranted as there is mounting evidence to suggest that omega-3 fatty acids play a role in depression.
8. Helps with postnatal depression
Whether it’s due to low intake or rapid depletion during pregnancy and breastfeeding, low omega-3 levels are a risk factor for postnatal depression.
A 2018 review concluded that dietary supplementation with EPA and DHA during and after pregnancy might help to reduce the risk and symptoms of the condition.
9. May benefit ADHD
Omega-3 fats are essential for brain and nervous system function. Low DHA in infancy could increase the risk of ADHD in early life.
A 2015 study ran over 16 weeks and gave 40 boys with ADHD versus 39 typically developing boys, 650mg EPA and 650mg DHA daily.
The outcome was positive for both sets of boys versus the placebo group, with parents observing a significantly positive effect on their attention span.
Another trial showed that supplementing with omega-3 fats, specifically DHA, may improve literacy and behaviour in children with ADHD.
10. May protect against childhood allergies
Promising research suggests that fish oils may help to protect against childhood allergies.
Some evidence indicates that eating fish during pregnancy may reduce the risk of atopic conditions for offspring and children who eat fish in early childhood.
Fish oil supplements could protect against the effects of pollution and dust mite allergies in children and may also protect against food allergies.
11. Protects vision, eye function
Our eyes need omega-3 fats to function correctly. Both your brain and eyes have high DHA content.
DHA is concentrated in the retina’s outer rod segments and is associated with better quality vision. It’s accumulated in the eyes late in pregnancy and in early infancy.
Low levels of omega-3 fats EPA and DHA are linked to age-related macular degeneration (AMD), so eating fish is associated with a decreased risk.
Dietary supplementation with omega-3 fats may also help to slow the progression of AMD for those at an early or intermediate stage of the condition.
A combination of EPA and DHA, lutein and zeaxanthin may also help reduce AMD risk.
12. May ease symptoms of rheumatoid arthritis
Fish oils have potent anti-inflammatory powers, which may help relieve the pain associated with osteoarthritis and rheumatoid arthritis.
EPA and DHA may also help to improve joint lubrication.
While research is limited, some sufferers of rheumatoid arthritis experience relief from their symptoms when supplementing with fish oils.
Some clinical trials also report the ability of omega-3 fatty acid supplements to relieve arthritic pain as effectively as NSAIDs like ibuprofen.
One trial had similar neck and back pain results, with 125 patients taking 1200 to 2400mg fish oils daily for 75 days. 59% discontinued their NSAID prescription for the pain, 60% said overall pain had improved, and 60% also stated their joint pain had improved.
13. Can promote thick, lustrous hair
Fish oils may help to improve hair quality and thickness.
Women with female pattern baldness may reduce hair loss and improve hair growth by including fish oils in their diet.
14. Encourages healthy skin
An unhealthy ratio of omega-6 to omega-3 increases inflammation and affects your skin. Fish oils can help you reach a healthier 2:1 ratio.
EPA and DHA may help to improve skin barrier function and hinder UV-induced inflammation and hyperpigmentation. Omega-3 fats can also help to relieve dry, itchy skin caused by dermatitis.
Fish oils also have anti-ageing effects, hydrating and improving skin tone, protecting collagen and preventing premature skin ageing.
While research varies, it’s clear that omega-3 fats and fish oils have a wealth of health benefits.
EPA and DHA from fish oils are vital for many bodily functions, including neurological and brain development and healthy vision.
Their potent anti-inflammatory and immune system modulating effects may help to protect against several diseases, including heart disease, diabetes and cancer.
Adding more oily fish to your diet twice a week is a healthy way to obtain adequate amounts of EPA and DHA. Plus, you also get all the other nutrients whole fish provides.
If you suffer from chronic disease or are taking medication, always seek medical advice before taking any supplements or changing your diet.