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What You Need To Know About Omega-3 Fats

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Quick Summary tl;dr

Here is your Omega-3 hierarchy: (1) Lyso-DHA from kill oil or fish eggs (roe), (2) EPA/DHA from sockeye salmon and other SMASH fish (3) ALA from plants.

Lyso-DHA gets privileged access to the brain, making it the best of the best Omega-3. Lyso-DHA is concentrated in krill oil and fish eggs (roe).

Sockeye salmon are an awesome source of DHA because they contain DHA's cellular body guard, astaxanthin.

Salmon, mackerel, anchovies, sardines and herring (SMASH fish) are great for EPA/DHA!

To get the most out of Omega-3 from plants, like flax and chia, add turmeric & black pepper to boost conversion of ALA into EPA/DHA.

Table of Contents

Everyone can agree that Omega-3 fatty acids are good for you, period! They are good for your brain, heart, gut, muscles, and basically everything else. But, as is always the story with nutrition science, the topic is a bit more nuanced. Here, we are going to unpack the wonderful world of Omega-3s.

To watch our 6 minute video, click here.

What You Need To Know About Omega-3 Fats

Understanding Three Types of Omega-3 Fatty Acids: ALA, EPA & DHA

The first thing to know is that there are three types of Omega-3 fatty acids. They are:

  • short-chain alpha-linolenic acid (ALA)
  • long-chain eicosapentaenoic acid (EPA)
  • long-chain docosahexaenoic acid (DHA)

Sources of ALA include certain nuts and seeds, in particular flaxseeds and chia seeds. EPA and DHA are derived mostly from fatty seafood.

Eat SMASH Fish: Salmon, Mackerel, Anchovies, Sardines, Herring

Here’s a helpful acronym to help you remember the most common sources: SMASH!

SMASH fish include salmon, mackerel, anchovies, sardines, and herring. (For practical reasons, salmon, mackerel and sardines are probably your best options. That’s because anchovies and herring are often canned with excess sodium or sugar, respectively. But if you buy them wild and fresh, that's not a problem.)

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Choose Fatty Seafood Over Nuts and Seeds

If you remember nothing else from this update, remember this: EPA and DHA are better than ALA!

Therefore, you should aim to consume seafood for Omega-3s, rather than solely rely on nuts and seeds. Now, that’s not to say nuts and seeds, like flaxseeds and chia seeds, are bad or useless. In fact, ALA can be converted in the body into EPA and DHA. Unfortunately, this conversion only occurs at extremely low levels. Estimates vary, but the conversion rate of ALA to EPA/DHA is generally thought to be 5% or less.( 1)

What You Need To Know About Omega-3 Fats

Are You Vegetarian? Add Turmeric & Black Pepper, or Algae Oil

Are vegetarians doomed to a life devoid of EPA and DHA? Well, not exactly. We have two recommendations for vegetarians. The first involves one of our favorite spices, turmeric!

An experiment in rats showed that supplementing rats with ALA and turmeric increased the expression of proteins that transform ALA into EPA and DHA. It also showed that the ALA plus turmeric combination actually increased levels of DHA in the rats’ brains! ( 2) Granted, this is a rodent study, and animal data don't always translate into humans. But given that certain studies, like this one, require lopping off heads at the end of the intervention, I think we can give that a pass. Something tells us it would be hard to recruit people for such a study. Agreed?

Therefore, vegetarians might consider consuming turmeric (or curcumin supplements) when they eat plant sources of Omega-3s. Adding some black pepper increases curcumin absorption and enhances the process. Another option for vegetarians is to take algae oil supplements. Algae oil contains EPA and DHA just like fish. In fact, fish get EPA and DHA mostly from eating algae.

To get the most out of Omega-3 from plants, like flax and chia, add turmeric & black pepper to boost conversion of ALA into EPA/DHA.

Best of the Best Omega-3 Fats For Your Brain

So, EPA and DHA are better than ALA. Is that it? As it turns out, the power of DHA — which is the canonical brain super fat — can be further enhanced if it’s attached to a lipid called phosphatidylcholine. This form of DHA is called “lyso-DHA.” Lyso-DHA is the best of the best Omega-3. That’s because it is more bioavailable and gets privileged transport into the brain via a transporter called MSFD2A. ( 3)

One epidemiological study followed 899 elderly people from the famous Framingham-offspring cohort for an average of 9.1 years. They observed that subjects who had higher blood lyso-DHA levels had a 47% reduction in risk of developing all-cause dementia. (All-cause dementia includes Alzheimer’s disease.) These subjects had an average fish intake of 3 servings per week. ( 4)

A study in piglets built on this correlation. They found that providing the baby squeakers with lyso-DHA formula caused incorporation of DHA into their growing brains that was twice as efficient as normal DHA! ( 5) Even better news came from a double blinded, randomized placebo-controlled, crossover trial in humans. (That’s jargon for, “a really good type of study.”) This study found that a lyso-DHA supplement, in the form of krill oil, was better at improving Omega-3 levels than just a regular EPA/DHA fish oil supplement. ( 6)

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Best Lyso-DHA Sources are Roe and Krill Oil

The best sources of lyso-DHA are salmon caviar, as well as fish eggs (roe) from other species, and krill oil. For reference, most EPA/DHA supplements contain no lyso-DHA. SMASH fish contain about 1.5% lyso-DHA. Finally, fish roe and krill oil each contain upwards of 35% lyso-DHA! Huh. Maybe that barracuda from Finding Nemo wasn’t evil but just nutritionally informed.

The best of the best Omega-3 is Lyso-DHA, which has privileged access to the brain. Krill oil and fish eggs (roe/caviar) are rich in Lyso-DHA.

Sockeye Salmon: The Redder the Better

The end? In science, never! Omega-3s don’t exist in food alone, and it’s important to consider the broader whole food when choosing your Omega-3 sources.

For example, we love sockeye salmon in particular as a source of EPA and DHA. Not only is it a great source of Omega-3s, but it comes packaged with a cellular bodyguard for our healthy fat friends called “astaxanthin.” Astaxanthin is the antioxidant that gives sockeye salmon their lovely red-pink color.

Why is astaxanthin so important? Omega-3 fats are fragile and prone to damage by the process of “oxidative stress” which is when free radicals damage other biomolecules. But astaxanthin protects EPA and DHA from oxidative stress! In fact, salmon evolved to increase their expression of astaxanthin during their upstream journey to spawn. This specifically protects their own EPA and DHA from the oxidative stress that occurs during this marathon trek. When it comes to selecting your sockeye salmon, remember, “the redder the better!”

When it comes to salmon, the redder the better. Redder salmon have more astaxanthin, which protects Omega-3 fats. Alaskan sockeye is the best.

Omega-3 Summary: What to Remember

In summary of the Omega-3 hierarchy:

  • Lyso-DHA is the best, and EPA and DHA are better than ALA.
  • Aim for salmon caviar and krill oil for lyso-DHA, and SMASH fish (salmon, mackerel, anchovies, sardines, and herring) for EPA and DHA.
  • If you’re a vegetarian, consider having flaxseeds and chia seeds with turmeric and black pepper, or consider getting an algae oil supplement.

What You Need To Know About Omega-3 Fats

Considering Omega-6 Fatty Acids

Mind Your Omega-6/3 Ratio

But just as important as considering astaxanthin is considering Omega-3’s mischievous sibling, Omega-6s. Don’t get us wrong, your body does need some Omega-6s to function, but most of us consume far too much.

An ideal Omega-6/3 ratio is 3:1 or below, but most Americans have a ratio of 12:1 or above. This high ratio can increase inflammation, which is another harmful cellular process that goes hand-in-hand with oxidative stress. Inflammation is associated with chronic diseases ranging from obesity to cardiovascular disease, diabetes, metabolic syndrome, and Alzheimer’s disease. Therefore, it’s important to be mindful of not only your Omega-3 intake, but your overall Omega-3 and 6 balance.

Let us provide an example. Let’s say you have a yummy 6-ounce fillet of sockeye salmon, containing about 1.9 grams of Omega-3s, but you cooked it in 2 Tbsp of grapeseed oil. Unfortunately, that amount of grapeseed oil contains about 19 grams of Omega-6s, putting your Omega-6/3 ratio at an alarming 10:1! Yikes

Cooking Oils: What to Embrace and What to Avoid

In terms of lower Omega-6 cooking oils and fats, we recommend macadamia nut oil, ghee, virgin coconut oil, or beef tallow. Avocado oil and butter are a pretty good option too!

Oils we recommend avoiding include grapeseed oil, soybean oil, corn oil, and really any nut or seed oil that is not macadamia or avocado.

To reduce your Omega-6 intake, and improve inflammation, use ghee, virgin coconut oil, or macamia nut oil when cooking. Don't use vegetable oils.

Omega 3 and Omega 6 Fats in Nuts

Certain nuts, like walnuts, are perceived to be great sources of Omega-3s, but there are two catches. First, all those Omega-3s are ALA. Second, walnuts contain about 4.5 times as much Omega-6 fat as Omega-3 fat. Therefore, their overall Omega-6/3 ratio isn’t ideal and the Omega-3s that are present are only ALA.

If you want to get mathy and apply the 5% ALA to EPA/DHA conversion rate, then that reasonable 4.5:1 ratio jumps to a ghastly 90:1 ratio. Perhaps consider swapping in some lower Omega-6 nuts, specifically macadamia and hazelnuts.

Walnuts are not a good source of Omega-3. They don't contain EPA/DHA and they have far more Omega-6 fats. And never heat a walnut above 130 °C/ 270 °F.

What You Need To Know About Omega-3 Fats

Should I Take Omega-3 Supplements?

We are often asked if it’s okay to supplement Omega-3s, rather than consume them in whole foods. In general, whole foods are a preferable source of Omega-3 fatty acids for three reasons:

  • Omega-3s in whole foods come the way that nature intended, cleverly packaged with molecules that support their function, like astaxanthin. This actually goes for Omega-6s too.
  • Omega-3s in whole foods are often themselves in more bioavailable forms, like lyso-DHA.
  • Finally, and perhaps most importantly, Omega-3 supplements often contain oxidized Omega-3s. It’s really hard to know if your supplement contains fresh or damaged Omega-3s.

Vegetarians can do with algae oil, as there aren’t many better options, and those wanting extra can supplement, but it’s always best to eat whole foods as your primary source of Omega-3s.

How to Include More Omega-3 Fats in Your Diet

So, let’s do like a sushi chef and wrap-up, but with practical advice rather than sticky rice.

1. Eat Wild Caught Fish

Try to eat wild-caught fatty fish at least twice per week. Certain people might benefit from more fatty fish. These include those carrying a gene variant called ApoE4. ( 7)

2. Fresh and Frozen Fish is Better than Canned

When buying seafood, opt for wild caught fresh or frozen, when possible. Fish in jars or cans often have added sodium, sugar, or the Omega-3s have become damaged.

3. Make Smart Seafood Choices to Minimize Mercury Intake

Also, try not to eat high-mercury fish too often, including tuna, swordfish, and king mackerel. Fish that are lower on the food chain have lower levels of this heavy metal. You can learn more about fish & seafood in this post: Complete Guide to Healthy and Sustainable Fish & Seafood.

4. Include Sources of Lyso-DHA

The best sources of marine Omega-3 are salmon caviar, other fish roe, and krill oil. They are followed by sockeye salmon, which is rich in astaxanthin, and other SMASH fish.

5. Are You Vegetarian? Include Flax, Chia and Turmeric

If you’re vegetarian, flax and chia seeds are good sources of ALA. Consider the turmeric & black pepper trick (curcumin in turmeric helps your body convert ALA into DHA, and black pepper increases curcumin absorption and enhances the process), or consider adding algae oil. If you’re ovo-vegetarian, this also means you can buy Omega-3 rich eggs and use turmeric to make yummy Golden Eggs or Golden Porridge!

6. Balance Your Omega 3 and Omega 6 Fats

Everyone should also keep in mind, not just their Omega-3 intake, but also their Omega-6 intake. Ideally, you want a low Omega-6/3 ratio of close to 3:1, or even below. Seafood is high in EPA and DHA Omega-3s and low in Omega-6s.

7. Choose the Right Type of Nuts & Seeds

Flaxseeds and chia seeds are high in ALA and low in Omega-6. Other nuts and seeds tend to contain more Omega-6. In particular walnuts (never roast a walnut above 130 °C/ 270 °F unless you want to munch on a load of oxidized fat), hemp seeds, and peanut butter. (If you’re a peanut butter addict, choose Pic’s Australian peanut butter. It comes from peanuts cultivated to have a more olive oil-like fat profile).

It’s hard to say any whole real food is “bad.” But practice moderation and consider macadamia nuts and hazelnuts as great low Omega-6 options.

WOW! That was a lot. But we know your brain can handle it because it’s now well supplied with DHA, right?

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What You Need To Know About Omega-3 Fats

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Comments (20)

Nick, any idea if basil seeds are also Omega-3(although ALA) dominent than Omega-6 just like chia seeds. Would you suggest incorporating them as well in food just along with chia seeds?

About 1/2 the fat in basil seeds is ALA. So, similar to chia in that respect.

Pic's peanut butter has half the PUFA(0.25g) of macadamia nut of 1 tbsp each( Does that make Pic's peanut butter as good as macadamia nut butter, if not better? Omega-7 is unique to macadamia but would you say that we can munch on a lot of this peanut butter like we can do for macadamia? Would your answer change if the peanuts were soaked for 12-24 hours?

Both Pic's and Macadamia nut butter state <0.5 g PUFA per serving>.
However, a Pic' serving is defined at 2 Tbsp and the Woolworth's macadamia nut butter you reference is 1 Tbsp/serving. If you take these figures to be accurate, then Pic's is lower in PUFA by half. But I have five points to make.
(1) I don't take these numbers to be accurate. Nutrition labels round, usually to the nearest 0.5, so the two-fold difference you are noticing is likely due almost entirely to rounding.
(2) Even if there were a two-fold difference in relative PUFA content, it's the absolute PUFA content that matters. In the scheme of your diet, the difference (were it to exist) of 0.25g PUFA per Tbsp nut butter is almost meaningless.
(3) the Palmitoleic Acid/Omega-7 content of macadamia nut butter further boost is fat profile, giving it another edge of peanut butter.
(4) Peanuts butter still has more anti-nutrients, like lectins and phytates, as compared to macadamia nut butter.
(5) Macadamia nut butter is intrinsically lower carb than peanut butter by several-fold.
In my opinion, Macadamia nut butter wins the day over Pic's and I, personally, would not be as comfortable snacking on even Pic's too liberally because of the lectins/phytates, higher carb/sugar content, and the fact that I'm not sure I entirely trust the nutrition label. But that's me, and I'm a more purist than most.
I hope those five points clarify things for you.

What test(s) should one take to find the mercury levels? And what are the permissible values beyond which one should worry about it?

You can get a blood test or do a 24-hour urine collection test. Most labs should be able to order it and the former is more common. The exact acceptable range depends on the exact assay and device being used and will be reported on the lab results as a reference range.

A great, short, punchy and informative video...and yes, I would love to see more of these types of simple explanations. Personally I worry about the harvesting of Krill Oil for the worlds population, but I understand why. Also, there is surely not enough Alaskan Sockeye Salmon to supply us all, so Martina, what kind of salmon would you recommend to those of us in UK/Europe, and where can we buy it? Sorry, big question! 😊
Thanks for the video.

If you want to get local fish in the UK, you're going to be stuck with Atlantic salmon. The Pacific species (pink, coho, chum, chinook, steelhead, cutthroat, and sockeye) are, obviously, in the Pacific ocean. When I was living in the UK, I generally bought fresh mackerel, which seems more widely available in the UK.  It's an awesome fish for EPA/DHA, and the fattiest of the SMASH fish. It doesn't have Astaxanthin, but that doesn't make it bad. Canned sardines in brine are also great, and cheap (40 pence at Tesco for a 84 g can), and eating the whole organism comes with added benefits and nutrients.

As I said, I do worry about the harvesting of Krill, especially Antarctic Krill. If we all took Krill Oil, and the this lucrative market got bigger, it could unbalance the marine ecosystem.  Just saying!

I understand and appreciate your point of view. Climate change management and animal welfare are important issues for me. I used to be a fundraiser for the WWF and work in pet shops in high school. But when it comes to health and nutrition, I try to separate the issues of health and environment. When I haven't, the conversation gets very messy very quickly. I've determined it's not for me to dictate how others live their lives with respect to consuming purely sustainable products or not. For example, I know a lot of people who claim carnivore has cured their severe diseases. Who would I be to challenge that claim or assert that they should abandon something that works for them because it wouldn't be sustainable if the whole world did it. I also try to think deeply about the relative impact of certain lifestyles choices. For example, going vegan only decreases your carbon footprint, relative to an omnivore, by half a one-way transatlantic flight per year. That's basically nothing. And it assumes factory farming, not regenerative agriculture, which is an important tangential point because it highlights the fact that it's not usually the food product that is "bad" for the ecosystem, but the way we produce it. We need to change the way we do agriculture for sure. On that we can agree.

Hi Nick, do you take krill oil? If so, do you have a good brand to recommend? I read your post about olive oil and was wondering if similar rules apply to krill oil. Thank you

In general, I don't recommend any specific supplements for the general population. Instead (besides vitamin D3 for those who live at higher latitudes), I think supplement protocols should be developed for individuals based on their needs and goals.
This is a preface to my short answer -- yes -- I do take krill oil. I use this brand, "Bulletproof": I know a bit about the company and its products are pretty reputable. It contains krill oil mixed with other fatty fish oil and EPA/DHA in a 2:1 ratio, which is supposed to be ideal for reasons explained in my response to Lina, and added Astaxanthin to protect the EPA and DHA.
I included the caveat above because what I do is not necessarily what you should do/need to do. I get what might be an excessive amount of omega-3 for most people, about 9-12 grams per day from salmon, mackerel, sardines, other fish and fish roe, and krill oil. This is in large part because I'm ApoE4/4, which means I'm part of 2% of the population that oxidizes EPA/DHA as fuel at a highly elevated rate, leaving less as substrate for the brain. Therefore, I think it makes sense to have higher levels of EPA/DHA in my diet, and particularly lyso-DHA. I also find I feel best when my omega-6/3 intake ratio is <2:1 (though that could be a placebo effect).
If you have the disposable income, adding this brand of krill oil certainly won't hurt you, but unless you have an ApoE4 allele, you can probably get away with getting most of your omega-3 from Whole Foods without the need to supplement.
Hope that help. Oh, and to answer your other question, I don't have a set of guidelines for selecting high-integrity omega-3 supplements as I do for my EVOO blog. I would simply research the company. I don't agree entirely with everything Dave Asprey puts forth, but I do think has integrity and so trust bulletproof.
Cheers mate!

Is any fish roe good to consume regularly or would you say that its best to get the roe from SMASH?

I think it's more of an affordability issue and I believe Nick will confirm that. SMASH fish is a more affordable way to get Omega-3 fats. I eat salmon roe just like Nick 1-2 tablespoons, small amounts a few times a week, usually for breakfast/lunch with fried/poached eggs and spinach.

I confirm that -- it's more of an affordability issue. But, yes, any fish roe is good fish roe.

Hey guys, I am LOVING these videos. I can't believe how much I learnt in just 5 minutes! I feel like I already know so much more about omega-3 fats, thanks to you Nick. I knew that DHA was the best option but didn't know why, and I knew that that ALA and EPA are in plants but didn't know about the poor conversion, or about the role of turmeric and algae oil. I think the omega-6 to 3 ratio is so bad if you eat SAD. Most people I know don't even like fatty fish!
I have a question about caviar. Apart from salmon is there any difference between different types of caviar? Some are very expensive and I wonder if the cheap caviar is ok for omega-3 fats.

I'm so glad you got something out of the video Lina! First, a quick clarification, plants don't contain EPA, just ALA. ALA is 18-carbons long and gets elongated into 20-carbon EPA, which can be turned into 22-carbon DHA. ALA doesn't get turned into either EPA or DHA well by the human body. Also, it's better to have a mix of EPA and DHA and some studies even suggest EPA😄HA ratios of 2:1 might be preferable. I think this derives from the fact that EPA can compete with omega-6 linoleic acid for the latter conversion into inflammatory AA. Therefore, I don't know if that "ideal" ratio applies in the content of a low omega-6 diet. But to get to your question, I've never heard of cheap caviar, unless you consider buying raw whole cod roe sacks from your fish monger, if they can provide. I did this as a student at Oxford and bought 3 kilogram roe sacks for 20-30 GBP! Super cheap and fresh. Assuming that's not an option, then I'd generally say that caviar from salmon or other fish is probably not a cost effective way to get omegas. If you want lyso-DHA, I use either krill oil supplements or - as a nice treat - I buy this in bulk and store it in the freezer. It's expensive, but when bought in bulk it's less so: I slice off ~2 tbsp worth and just eat it from frozen when I want something sweet. To me, at least, it tastes like keto ice cream. Go figure. Maybe put it on your Christmas list ;).

You're right! Sometimes what you want to say doesn't translate into what you write :-D Thank you so much, this was really helpful!
And you're right again, all caviar is expensive. It's just that some is ridiculously expensive.  I had no idea there was something like cod roe. I'll need to check that out. Would you recommend just a small amount, maybe 2 ounces per serving of cod roe or can it be eaten like fish 4-5 ounces? I'll definitely get some salmon roe in bulk, and krill oil. My wish list is full now! 😊 Thank you for all you do!

You know how they say too much of a good thing is a bad thing? Well, when it comes to cod roe, I disagree. If you can find it cheap and fresh, pack it in 😊. 5 ounces as your protein for a meal should be great! Your brain will love you for it.
Martina can verify that I have, right Martina? ;) Also, maybe Martina can post a taramasalata recipe? I know we have one in our book!
& Your Welcome. To know that you get something from our videos, posts and recipes makes it all worth it.

Thank you Nick, I think we certainly need to share that recipe here, it's too good to keep it in the book only 😉