In the world of nutrition, few supplements have gained as much attention as fish oil. From heart health to brain function, omega-3 fatty acids are often described as essential for overall wellbeing. But what exactly is fish oil, who should take it, and are supplements really necessary? Here’s a complete guide to understanding fish oil.
What is Fish Oil?
Fish oil is a type of oil extracted from the tissues of oily fish and is one of the richest dietary sources of omega-3 fatty acids. These are essential fats that the body cannot produce on its own and must be obtained through food or supplementation.
The two primary omega-3 fatty acids in fish oil are:
EPA (Eicosapentaenoic acid): Known for reducing inflammation and supporting heart health.
DHA (Docosahexaenoic acid): Crucial for brain development, eye health, and nerve function.
According to Sameera Sheikh, Clinical Dietitian, Microbiologist, and Functional Medicine Expert, these are naturally present in fatty fish such as salmon, sardines, mackerel, and tuna. While some plant foods provide ALA (alpha-linolenic acid), fish oil specifically delivers EPA and DHA in usable forms.
Types of Fish Oil sources
Not all fish oil supplements are the same. As per the expert, the source determines the nutrient profile and additional components.
Standard Fish Oil
Standard fish oil is extracted from the flesh of fish like salmon, sardines, tuna, and mackerel. Containing both EPA and DHA, this is the most commonly used and widely available supplement type.
Cod Liver Oil
Derived from the liver of cod fish, this one contains EPA and DHA along with Vitamins A and D. While beneficial for immunity and bone health, excessive intake can lead to Vitamin A toxicity, so dosage matters.
Krill Oil
This one is extracted from small crustaceans called krill, where omega-3s are present in phospholipid form, allowing better absorption. Krill oil contains the antioxidant astaxanthin and may cause fewer fishy burps. It typically provides a lower omega-3 dose per capsule compared to standard fish oil.
Salmon Oil
Salmon oil is a popular source rich in omega-3 and omega-6 fatty acids.
Algal Oil
Algal oil is a vegetarian option, derived from marine algae. Rich in DHA and sometimes EPA, it is a sustainable and mercury-free alternative ideal for vegetarians and eggetarians.
Fish Oil Supplements: How to consume them
Fish oil supplements are available in various forms to suit different needs.
Capsules / Softgels
Capsules or softgels are the most common format of fish oil supplements. They are easy to swallow and have minimal taste. Sameera explains, “It is best suited for adults, usually taken once or twice daily after a meal.”
Liquid Fish Oil
This one comes in syrup form, helpful for those who cannot swallow capsules. As per the dietitian, it can be mixed with juice if needed and is suitable for children and elderly individuals.
Chewable Fish Oil
Chewable fish oil features flavoured options like orange or lemon, especially designed for children. “It contains a lower dose than adult capsules,” says Sameera.
Who can consume Fish Oil?
According to Sameera, fish oil can be beneficial for specific groups when taken appropriately and under guidance where needed.
“Fish oil helps reduce triglycerides and supports heart health. It also has anti-inflammatory properties that may help in conditions like rheumatoid arthritis,” she explains, highlighting its therapeutic role.
Sameera suggests people who can consume and may benefit from fish oil:
People with high cholesterol or high triglycerides
Strong evidence shows omega-3 fatty acids significantly reduce blood triglyceride levels. There may also be a slight increase in HDL (good) cholesterol, though LDL (bad) cholesterol levels may rise in some cases.
People at risk of heart disease
Research shows people who eat fatty fish at least twice a week have a lower risk of dying from heart disease. However, supplements offer little to no additional heart protection compared to dietary sources.
People with joint pain or rheumatoid arthritis
Studies suggest fish oil supplements may reduce pain, improve morning stiffness, and relieve joint tenderness. While the relief is often modest, it may reduce reliance on anti-inflammatory medications.
Pregnant & breastfeeding women
“DHA supports baby’s brain and eye development. But dosage and purity matter, so always consult a gynaecologist,” Sameera advises.
Children with low omega-3 intake
Children with low omega-3 intake can take fish oil supplements to support brain and vision development. “Paediatric doses only,” adds the expert.
People who don’t eat fish
Vegetarians and eggetarians may consider algal oil as a suitable alternative source of DHA and EPA.
Benefits of Fish Oil
Heart health
Fish oil is strongly associated with lowering triglycerides, which is one of its most evidence-backed benefits. Multiple studies also report modest reductions in blood pressure among those taking supplements, particularly in individuals with moderate to severe hypertension. Sameera adds, “While eating fatty fish regularly is linked to reduced risk of death from heart disease, supplements alone appear to offer limited heart protection.”
Brain function
DHA plays a central role in supporting memory and concentration. As per the expert, certain formulations with higher EPA content may also be helpful in mild depression, making omega-3s important for overall cognitive and emotional wellbeing.
Eye health
DHA is a structural component of the retina and supports proper eye function. “Supplementation may help reduce symptoms of dry eyes and improve overall eye lubrication,” notes Sameera.
Joint and inflammation support
Omega-3 fatty acids have anti-inflammatory properties that can be beneficial in inflammatory conditions such as rheumatoid arthritis. Sameera explains, “Research shows that fish oil supplements may reduce joint pain, tenderness, and morning stiffness, although the improvements are generally modest.”
Pregnancy and baby development
During pregnancy, DHA is crucial for fetal brain and eye development. However, the expert suggests supplementation should always be taken under medical supervision to ensure correct dosage and purity.
Metabolic health
Fish oil plays a role in managing high triglycerides and may support fatty liver management. “It also fits well into anti-inflammatory dietary plans aimed at improving metabolic health,” adds the dietitian.
Possible side effects
Fish oil is generally safe when consumed in appropriate doses, but side effects can occur.
Common side effects include:
Fishy burps
Acidity or indigestion
Loose stools at higher doses
Nausea
Less common but important risks:
Increased bleeding risk at high doses
Drop in blood pressure in individuals with already low BP
Vitamin A toxicity with excessive cod liver oil use
Who should be careful?
Sameera advises, “People taking blood thinners such as aspirin, clopidogrel, or warfarin should consult their doctor before using fish oil. Those preparing for surgery, individuals with fish allergies, and pregnant women without medical supervision should also exercise caution.”
Safe general dose
“For general health, 250–500 mg of combined EPA and DHA daily is considered adequate,” suggests Sameera. Higher doses for managing high triglycerides should only be taken under medical supervision.
Fish oil can be a helpful addition to a balanced diet, especially for those who do not consume fatty fish regularly. The key lies in choosing the right type, maintaining appropriate dosage, and using supplements as part of a broad, healthy lifestyle rather than a quick fix.
