Omega-3 Fatty Acids: Foods, EPA, DHA & How Much You Need

What Is the Difference Between EPA, DHA and ALA?

One of the most important things to understand about omega-3 is that not all omega-3 fatty acids are the same.

EPA — Eicosapentaenoic Acid

EPA is a long-chain omega-3 fatty acid found primarily in oily fish, seafood and marine oils. It is incorporated into cell membranes and participates in the production of signalling molecules within the body.

DHA — Docosahexaenoic Acid

DHA is another long-chain omega-3 fatty acid. It is an important structural component of cell membranes and is particularly concentrated in the brain and retina.

ALA — Alpha-Linolenic Acid

ALA is the main plant-based omega-3 fatty acid and is found in foods such as chia seeds, flaxseeds and walnuts.

The body can convert ALA into EPA and DHA, but only a limited proportion is converted. This means eating chia seeds or flaxseeds is nutritionally valuable, but it is not exactly equivalent to consuming EPA and DHA directly.

What Foods Are Highest in Omega-3?

The best source depends on which type of omega-3 you are trying to obtain.

Foods Rich in EPA and DHA

Marine sources are generally the richest dietary sources of EPA and DHA.

• Salmon
• Sardines
• Mackerel
• Trout
• Herring
• Some types of tuna
• Mussels and other seafood

The actual EPA and DHA content varies substantially between different fish species and products.

Plant-Based Foods Rich in ALA

• Chia seeds
• Flaxseeds / linseeds
• Walnuts
• Hemp seeds
• Canola oil
• Some soy foods

Including these foods can be an excellent way to increase ALA intake, particularly for people following vegetarian or plant-based diets.

How Much Omega-3 Do You Need Per Day?

There isn’t one omega-3 number that applies to every person because Australian nutrient recommendations distinguish between different types of omega-3 and different nutritional targets.

For long-chain omega-3 fats, Australian nutrient reference values include Suggested Dietary Targets of approximately 430 mg per day for adult women and 610 mg per day for adult men for reducing chronic disease risk.

These figures should not be interpreted as a supplement dose that everybody needs to take.

Your actual intake can come from food, and individual requirements can vary according to diet, age, pregnancy, health conditions and other factors.

How Much Fish Should You Eat for Omega-3?

Regularly eating fish, particularly oily fish, can provide EPA and DHA alongside protein and other nutrients.

Rather than trying to calculate the omega-3 content of every meal, many healthy eating recommendations encourage including fish regularly within a varied diet.

Salmon, sardines, trout, herring and mackerel tend to provide considerably more long-chain omega-3 than many leaner fish varieties.

If you rarely or never eat seafood, it may be worth looking more closely at where your EPA and DHA are coming from.

Can Vegetarians and Vegans Get Enough Omega-3?

Yes, but the type of omega-3 matters.

Chia seeds, flaxseeds, walnuts and other plant foods provide ALA. These foods can form an important part of a healthy plant-based diet.

However, conversion of ALA into the longer-chain omega-3 fats EPA and DHA is limited.

For people who avoid fish and seafood, algae-derived omega-3 can provide a direct plant-based source of DHA, with some products also providing EPA.

This can be particularly relevant when reviewing the nutritional adequacy of vegetarian and vegan diets.

Is Fish Oil the Same as Omega-3?

No. Fish oil and omega-3 are not exactly the same thing.

Fish oil contains omega-3 fatty acids, primarily EPA and DHA, but the total amount of fish oil shown on the front of a supplement does not necessarily equal the amount of EPA and DHA it provides.

For example, a capsule labelled “1,000 mg fish oil” may provide considerably less than 1,000 mg of combined EPA and DHA.

When comparing products, look at the label for the actual quantities of:

• EPA
• DHA
• Total omega-3 fatty acids

This gives you much more useful information than looking at the total fish-oil number alone.

Fish Oil vs Krill Oil vs Algae Oil: What’s the Difference?

Fish Oil

Fish oil is a commonly used supplemental source of the long-chain omega-3 fatty acids EPA and DHA.

Krill Oil

Krill oil also provides EPA and DHA, although the amount per capsule and formulation varies between products.

Algae Oil

Algae-derived oils provide a fish-free source of long-chain omega-3 and can be particularly useful for vegetarians, vegans and people who do not consume seafood.

Rather than assuming one form is automatically “best”, compare the actual EPA and DHA content and consider why you are taking the supplement in the first place.

What Is the Difference Between Omega-3, Omega-6 and Omega-9?

Despite their similar names, omega-3, omega-6 and omega-9 are different families of fatty acids.

Omega-3

Includes ALA, EPA and DHA. ALA is an essential fatty acid and must be obtained through the diet.

Omega-6

Omega-6 fatty acids include linoleic acid, another essential fatty acid that must come from food. Sources include nuts, seeds and various plant oils.

Omega-9

Omega-9 fatty acids include oleic acid, which is abundant in foods such as olive oil and avocado. Unlike omega-3 and omega-6 essential fatty acids, the body can produce omega-9.

A healthy diet should therefore focus on overall dietary quality and appropriate sources of unsaturated fats rather than treating all omega fats as interchangeable.

Is Omega-6 Bad for You?

Omega-6 itself is not inherently “bad”. Linoleic acid is an essential fatty acid that the body needs and must obtain from food.

Rather than trying to eliminate omega-6 foods, it is generally more useful to consider the quality of your overall diet and whether you are regularly consuming omega-3-rich foods.

Nuts and seeds, for example, can provide omega-6 alongside fibre, protein, vitamins, minerals and other beneficial nutrients.

What Does Omega-3 Do in the Body?

Omega-3 fatty acids form part of cell membranes and participate in a range of normal physiological processes.

EPA and DHA are particularly relevant to:

• Normal cell membrane structure and function
• Cardiovascular health
• Normal brain structure and function
• Normal retinal structure and function
• Normal inflammatory signalling processes

However, this does not mean an omega-3 supplement will prevent or treat every condition associated with these systems. The evidence depends on the condition, dose, baseline diet and individual circumstances.

Omega-3 for Women

Omega-3 intake is worth considering as part of an overall nutritional assessment for women at different stages of life.

Rather than viewing fish oil as a “hormone balancing” supplement, we look at the broader dietary picture — including protein, iron, calcium, vitamin D, magnesium, fibre and the quality of dietary fats.

During perimenopause and menopause, maintaining a nutrient-dense dietary pattern becomes particularly important for cardiovascular, bone and overall health.

Learn more about perimenopause support at Morkare.

Omega-3 During Pregnancy

DHA has an important structural role in the brain and retina, which makes omega-3 intake an important nutritional consideration during pregnancy.

However, pregnancy is not the time to self-prescribe high-dose fish oil or assume every omega-3 supplement is appropriate.

Food choices, supplement quality, EPA and DHA content and individual medical circumstances should all be considered.

If you are pregnant, planning pregnancy or breastfeeding, discuss supplementation with an appropriately qualified healthcare professional.

Do Children Need Omega-3?

Omega-3 fatty acids form part of a healthy diet throughout childhood. Fish and seafood can provide EPA and DHA, while plant foods such as chia seeds and walnuts provide ALA.

If your child eats a very restricted diet, avoids seafood or has significant food allergies, their overall fat and nutrient intake may be worth reviewing.

Children should not automatically be placed on high-dose fish oil simply because of behavioural, developmental or concentration concerns. Supplement decisions should consider the child’s age, diet, health history and individual needs.

Learn more about our Paediatric Naturopath Brisbane service.

Do You Need an Omega-3 Supplement?

Not necessarily. If you regularly eat omega-3-rich fish and have an otherwise balanced diet, supplementation may not be required.

A supplement may be worth discussing when:

• You rarely or never eat fish or seafood
• You follow a vegetarian or vegan diet
• Your diet provides very few omega-3-rich foods
• You have been advised to increase EPA or DHA intake
• A healthcare practitioner has identified a specific clinical reason for supplementation

The goal should be to identify why supplementation is being considered rather than simply adding fish oil to an already long supplement list.

What Should You Look for in an Omega-3 Supplement?

If supplementation is appropriate, don’t choose a product based only on the largest number on the front of the bottle.

Consider:

• The actual EPA content
• The actual DHA content
• Total EPA + DHA per recommended serve
• Fish, krill or algae source
• Product quality and storage
• Your individual reason for taking it
• Whether it is appropriate with your medications and health history

Can You Take Too Much Omega-3?

More is not automatically better.

High-dose omega-3 supplementation is used in some clinical circumstances, but these doses should not be confused with general dietary intake.

If you take anticoagulant or antiplatelet medication, have a bleeding disorder, are preparing for surgery, are pregnant or have a significant medical condition, discuss omega-3 supplementation with your doctor or appropriate healthcare practitioner.

Should You Test Your Omega-3 Levels?

Omega-3 status can be assessed using specialised fatty-acid testing, but testing is not routinely necessary for everyone.

For many people, reviewing how frequently they eat oily fish and other omega-3 foods is a useful starting point.

If there is a specific clinical reason to investigate fatty-acid status, your practitioner can discuss whether testing would add useful information to your care.

Personalised Nutrition Support in Brisbane

If you’re unsure whether you’re eating enough omega-3, which type you need or whether a supplement is actually necessary, a personalised nutrition review can help simplify the decision.

At Morkare Natural Clinic, we look at your whole diet rather than one nutrient in isolation. Your practitioner can review your usual food intake, dietary preferences, health history, medications, supplements and nutritional goals.

This can be particularly useful if you are vegetarian or vegan, rarely eat seafood, are navigating women’s health changes or simply feel overwhelmed by conflicting supplement advice.

Learn more about our Clinical Nutritionist Brisbane service.

Appointments are available in-clinic at Holland Park West, Brisbane, and by telehealth Australia-wide.

Book a Clinical Nutrition Consultation