Wouldn’t it be great if we could eat whatever we wanted and take a pill afterward to make sure we get our daily micronutrient needs? Unfortunately, scientific studies have repeatedly shown that nothing replaces a good diet when it comes to our health.

When we talk about omega-3 fatty acids, there are some facts that need to be considered.

Not all omega-3s are created equal.

The European Food Safety Authority recommends a daily intake of 250 mg of long-chain omega-3 fatty acids (i.e., EPA + DHA, the omega-3s with proven health benefits). However, a food can claim to be “high in omega-3 fatty acids” if it contains at least 600 mg of alpha-linolenic acid or at least 80 mg of EPA + DHA per 100 g of food, and these categories are not the same.

Why? The Science Facts

Alpha-linolenic acid (ALA, C18 n-3), to provide health benefits, needs to be converted into EPA and DHA. Think of it as an assembly line: enzymes (they’re called “elongases,” which makes sense) in this specific pathway will take the 18 carbons (C18) of alpha-linolenic acid and add more carbon molecules to the end of the chain, to reach the 20 and 22 carbons of EPA and DHA, respectively (of course, this is a simplification: this metabolic pathway is quite complex, but that’s the general idea). Some fish species, like salmon and trout, are able to do this in significant quantities, but the human species (i.e., the reader and I) has limited bioconversion capacity (if any!) for these fatty acids.

How does this process work in the human body?

Simply put, we don’t have the necessary enzymes (nobody’s working on the assembly line). Therefore, while eating flaxseed is one way to get omega-3s, it probably won’t help keep your heart healthy! If you’re vegan, ideally you should consume microalgae rich in long-chain omega-3s, such as EPA and DHA. If not, eat fish, preferably oily fish. Plant-based sources of omega-3s, such as walnuts and flaxseeds, are also high in pro-inflammatory omega-6 fatty acids (I’d like to call them the “bad twins” of omega-3s, but honestly, they aren’t: we need balance and both have a place in our diet – just make sure the ratio between the two leans more towards omega-3s and your health will thank you).

Why should we worry about micronutrients in general and not just omega-3 fatty acids?

When our diet is highly processed, rich in simple sugars and trans fats, the resulting inflammatory state in our body can impair nutrient absorption. That’s why, if you’re on a SAD (Standard American Diet) and supplementing with omega-3 fatty acids, you probably won’t see any beneficial effects. It’s not that omega-3s in supplement form aren’t good for you, but you’re simply not absorbing them! This also applies to essential minerals like zinc and selenium, and vitamins. And you become obese but malnourished, a recipe for disaster.

And finally: fish is more than just omega-3 fatty acids!

Fish is rich in vitamins A and D, important minerals (iodine, zinc, magnesium, iron, selenium), and has low cholesterol levels, along with highly digestible proteins and a more complete fatty acid profile than a fish oil supplement. All these nutrients work together to provide the health benefits for which fish consumption is responsible. Studies show that while a supplement may provide a higher dose of omega-3 fatty acids than a serving of fish, EPA and DHA will be more easily absorbed from the latter. This is likely due to a synergy that occurs with the other fatty acids and nutrients present in fish muscle, helping our bodies use omega-3s more efficiently.

Plus, fish is delicious. What else do you need to know?

Elisabete Matos develops pragmatic and innovative solutions in the Blue Bioeconomy.

She is the Technical-Scientific Director of B2E, with a background in Innovation, and Nutrition and Quality of Fish.