Omega-3 – Creating a strong base for human nutrition

This work is the big challenge taken by Tri Phung.


Why nutrition matters to me, to you, and all human
A reference intake for Omega-3
Alpha Linolenic Acid (ALA)
EPA and DHA from whole food
Thought for the Planet
Ending note

The PDF version of this article is available here:


I am not a certified person in anything. I am assuming the readers of these texts are people in their 20s, very average, have no history of any sophisticated disease, and need no special requirements. What is written here is a sharing of my readings and limited knowledge. Because nutrition is a vast and highly individualized field, please take my words as a grain of salt. I would encourage you to investigate the matter yourself. Adapt what is useful, reject what is useless, and add what is specifically your own (Bruce Lee quote).

Why nutrition matters to me, to you, and all human

Delicious food brings joy, you can probably observe that during social events; meanwhile, to some people, the act of having food is joy already. So, besides its function as a social lubricant, food is fundamentally nutrition for humans.
Viewing peanut butter (I chose this example because I love peanut butter) under a minuscule scope, it delivers fat for cell functions and metabolism, protein for the reconstruction of new cells and tissues in replace of dead ones, sugar for muscular contraction which gives you the ability to perform every action with your physical body. In the digestive system peanut butter is further broken down to copper, magnesium, manganese, phosphorous, vitamin B3, folate, vitamin E.

In the world of exponentially rising population, it becomes a distressing challenge of how to deliver such a basic human right as nutrition to every living soul, while still maintaining the Earth integrity for other coexist organisms and for the human future generation.

On account of nutrition & responsible consumption, my creation is a guide for food choice, specifically, food for Omega-3 Fatty Acid, an essential macro-nutrient. After this, you will be equipped with applicable knowledge to adapt to your eating habits.

But before, let me explain why I choose Omega-3 fatty acid...
In the winter of 2017, I was living quite a hectic college student life. Time was juggled among Uni, deadlines, working, gym routine, eating, sleeping. Constant cycling was also part of my commute and work because I worked as a food delivery biker. The stress level was through the roof and constantly elevated. Unsurprisingly, I burn out and felt utterly like total crap physically and mentally.
My food choice was quite okay back then; the diet consisted of lean meat, chicken and pork, eggs, oatmeal, rice, potatoes, peanut butter, olive oil, some greens, and fruits here and there. I did not even think that my diet could be deficient in any nutrient until I happened to watch a YouTube video whose author is quite well-known within the YouTube fitness community. He mentioned a study by Sublette (2011), which published this finding:
"Supplements containing EPA ≥ 60% of total EPA + DHA, in a dose range of 200 to 2,200 mg/d of EPA in excess of DHA, were effective against primary depression".
That was when reality hit; I was severely lacking omega-3 fatty acid (ω-3) in my diet; I barely ate any fish nor any ω-3 food source. Intrigued, I did some research, looked up references, and from my understanding, I devised a mathematical model to choose a fish oil that delivered me adequate ω-3 and hopefully I would feel better after so many depression episodes. Ha! Engineering my way through depression.

As you who are reading this are probably in the middle of your hectic life, you would sympathize with this work to create a good nutritional base that can fuel your daily activities, and ω-3 must be a part of that base. So, in my work, I wish to deliver you an easily adaptable guide to have adequate ω-3 fatty acid in Finland. I also expand boundaries to cover suitable approaches for vegans, as well as providing environmental considerations for the ω-3 rich food.

A reference intake for Omega-3

I would not discuss much the role of ω-3 in human physiology, which is beyond my expertise. A quick summary would be that ω-3 exists in the human brain and eyes, so it should bring benefits to those two areas. Instead, my goal is to inform you how to get them into your body. There are three important names that you should pay attention to short-chain ω-3 alpha-linoleic acid (ALA), long-chain ω -3 eicosa-penta-enoic acid (EPA) and docosa-hexa-enoic acid (DHA).
WHO (2008) set a reference intake for ω-3 as: "The higher value 2% of total daily energy for ALA plus (0.25g to 2.0g) of (EPA + DHA) can be part of a healthy diet". For 2,000-kcal daily energy, 2% of that is equivalent to 4.4g ALA (2% x 2000 kcal x 9 kcal/g ALA). So, I will re-phrase the above recommendation as:
"4.4g ALA + (0.25g to 2.0g) (EPA + DHA) = a part of a healthy diet"

In addition, there are references for the most common source of ω-3 – fish. Fish meal at least twice a week, preferably from recognized/certified source (Finnish Food Authority; WHO 2018). For an average person needing 2,500 kcal/day, a range from 0 (minimum) – 28 (average) – 100 (maximum) grams of fish a day, with the total weekly intake of 200g fish/wk (28g/day x 7days = 196g/wk) for a healthy diet and sustainable planet (EAT-Lancet Commission 2019). It is not explicitly stated in the reference; my assumption of 200g is raw, before cooking mass.

Alpha Linolenic Acid (ALA)

Easy intake from whole food.

These three plant-based, wholesome, ALA-loaded foods can be incorporated in everyone’s food list:
GROUND linseed (19-24% ALA per food weight)
Also known as flaxseed, linseed must be ground before eating, otherwise, its nutrients cannot be digested. I think the name LIN-seed is not a coincidence, because it is laden with α-LIN-olenic Acid (pun intended).
Chia seed (18-22% ALA), and
Walnut (9% ALA)
A tablespoon of ground flaxseed (7g), a tablespoon of chia seed (12g), and 5 walnut pieces (half a kernel, 12g) can deliver 4.5g of ALA, which is considered a high value of ALA intake (2% 2,000 kcal/day). With that amount, you will receive the ALA benefits, which include cardioprotective (good for your blood and heart) and anti-inflammation (good for your active, dynamic, high-stress lifestyle) (Starl 2008; Rodriguez 2010). Apart from linseed, chia seed, walnut, I want to give honorable mentions to other ALA sources: hemp seed (6% or 9% ALA, depending on if the outer shell is removed), and grass-fed beef and butter.

In Finland, it can be economical to meet these intakes. Here are the bundles I often bought:

  • Chia Seed in Lidl’s Golden Sun €10/kg.
    Chia seeds can be expensive, especially in organic food stores (Ruhonjuuri, Pure…). I just stick with Lidl’s cheapest type.
  • Flax seed in S-market / Prisma / Sokos €3/kg
    Flaxseed, on the other hand, is cheap because it is a local planting species in Finnish agriculture. There is an already ground version, you can purchase instead of whole seed with slightly more costs (€3.5/kg). I am just convinced that grinding whole flaxseed and consume in a short time can retain more nutrition.
  • Walnut in Lidl or scoop-takeaway snack bag in Prisma €16/kg
    Walnut is also very expensive. I found a walnut bag price as high as 35e/kg! Maybe the organic farming model adds more overhead. But I just choose something that fits my student budget.

The above intake (7g ground flaxseed, 10g chia seed, 12g walnut) will cost me 40cent/day and €12/month. But I’ll be honest, there is no way I have the self-control to stop at 12g of walnut. I should also mention an additional investment for a €20 grinder in Verkokauppa. That grinder is OKAY, as there are some flax seeds unable to be ground.

Because a high amount of ALA is already covered with a reasonable price, supplements for ALA in pill or oil form is unnecessary.
ALA can convert in some extents to the ω-3 long-form EPA, but little or none to the longer form DHA. Also, the conversion rate has not met a scientific consensus, and apparently, it is not very efficient.

TABLE 1. Conversion rate from short chain ω-3 ALA to long chain ω -3 EPA & DHA

[1] Starl et al. 2008; [2] Burdge et al. 2005; [3] Gerster 1998; [4] Williams et al. 2006

In a hypothetical undesirable scenario, that is, an adult male with diet high saturated fat (e.g. meats, eggs, milk, coconut), the planned 4.5g ALA intake will convert to 0.27g EPA & 0.004g DHA. In that sense, that person already meets the minimum requirement of 0.25g for (EPA + DHA).
However, because of high uncertainty, eating ALA may not be enough to provide sufficient (EPA+DHA) and comprehensive ω-3 profile. Therefore, the ω-3 long-chain form EPA and DHA are recommended for direct consumption, in the form of at least two fish meals per week. Dear Vegan folks, worry not, read more on the next section to explore the plant-based option for your EPA & DHA intake.

EPA and DHA from whole food

Easy intake from fish, but a bit "fishy" without.

Fatty fish is the source of EPA & DHA. Salmon, Sardines, Herring, Mackerel, and Tuna are common fish in Finnish grocery stores and a wildly wide variety.

TABLE 2. Fish, its abundant ω-3 amount (Data: Fineli)

Data source



DHA (g)


Tuna, Albacore (Thunnus alalonga), in water, drained from can, 80g





Tuna, Albacore (Thunnus alalonga), in oil, drained from can, 80g





Herring, Baltic (Clupea harengus membras), drained from can, 85g





Tuna, Atlantic bluefin (Thunnus thynnus), raw, 100g





Herring, Atlantic (Clupea harengus harengus), in garlic/mustard sauce, 100g





Sardines, cooked, in oil and tomato sauce, 85g





Herring, Atlantic (Clupea harengus harengus), drained from salted can, 80g





Mackerel fillet, Baltic (Scomber scombrus), drained from tomato sauce can, 80g

Deduced from Lidl Nixe package label




Salmon, Atlantic (Salmo salar), raw, 100g





Mackerel, smoked, 75g






Apart from Albacore tuna, a serving of other fish (each serving is regarded as 80 85g cooked or 100g raw) easily delivers a high dose of (EPA+DHA). Because it is recommended to have two fish meals, for a total of 200g, per week (WHO 2018; EAT-Lancet Commision 2019), and a diet with a variety of species (Finnish Food Authority), you may start with a can of mackerel (makrilli), a can of sardines (sardiinit) in one week, then explore from there. If you happen to like tuna, mix in aioli or mayo, spread on salad and sandwich, you may want to search for the Atlantic bluefin type.
In Lidl, a can of mackerel and a can of sardine both cost €1; a can of herring is up to €2. So, two cans per week amount to €2 - €3, adding up to €12 per month. If you have fancy money in the pocket, you can opt for raw fish meat and create delicious dishes.
Vegan folks, here is my promise to you, let’s explore alternatives for EPA & DHA without animal source. Fish do not synthesize ω-3 on their own. Instead, they got it from their diet: micro (very small)-algae. The ω-3 fatty acid transports from plant, to small fish, to bigger fish, and subsequently to our plate. So, what if, human bio-mimic and consume the primary producers of ω-3, and in our case, an option will be macro (big)-algae – seaweed?

I bring bad news for you; seaweed is not a reliable food source to reach enough amount. Seaweed is low in fat content, and among the total fat, only a fraction is EPA or DHA. If the minimum value of 250 mg (EPA + DHA) is to be met, 40g dried Dulse and 40g dried Sargassum seaweeds would have to be eaten. But you will get iodine poisoning and break a bank before finish eating that amount. Seaweed should be incorporated in human’s meal plan for their nutritional benefits and contribute a part to total ω-3 intake, but they cannot deliver an effective ω-3 amount as fish can.

TABLE 3. Seaweed, its limited ω-3 absolute amount (Data: van Ginnerken et al. 2011)


& an interesting trivia to fix your down mood

First thing first, I strongly believe that the foundation of everyone’s nutrition should be built around whole food; nuts, seeds, and fish are the base for ω-3. If you have an extra budget and want an extra layer of insurance, then and only then, go for supplements as a cherry on top.

However, as discussed above, vegan folks may have difficulty in obtaining long-chain ω-3 from whole food, so for them, supplementation is a wise strategy. Or, people living near contaminated water regions may need to blacklist fish to avoid poisoning, then supplementation may be a better option.

Supplements are very frustrating; there are too many brands on the shelf as well as too different amounts and ratios. That is why label reading is a skill that I considered an asset in this consumerism-loaded world. (Check what Tatjana started on that topic !) On a label, you can see the amount of EPA and DHA in one serving. That can be one pill a day, three pills taken with three meals per day, etc. If the supplement offers the minimum 250 mg (EPA + DHA) for one-day dosage, then that may be the first sign of a decent one.

In the figure below, I present several options for omega-3 supplements in Finland. Some are from health & welfare brands; some are from gym & training brand. There are some "grocery store" brands that I do not mention. When you come across them in Lidl, Prisma, or K-market, you can apply the logic to decide your purchase. I also categorize into three sources: (i) fish, (ii) plant-based: microalgae or seaweed, and (iii) krill.

Then, I think your buying decision will boil down to these factors:
General well-being: if you are after this goal, fish oil that has more than 250mg (EPA + DHA) per daily recommended dosage may suit your need. However, if you already established a food foundation consisting of adequate fish, nuts, and seeds, I wholeheartedly advise you to save money from unnecessary supplements.
Avoid animal products: Of course, the plant-based options are designed to target customers who do not want to consume animal-derived products. If that is also your, you should choose a plant source supplement that delivers more than 250 mg (EPA +DHA) in its daily stated dose.
Schizochytrium microalgae seem to be the most common species used in supplements; its constituent is dominantly DHA and low(er) in EPA.
Specific health:
Astaxanthin: Krill, the tiny creature living around Antarctica, provide ω-3 and astaxanthin, which does have health-boosting properties. However, I have no experience nor done a thorough background reading about this yet, so I will leave this matter aside, and invite you to research yourself. I have anecdotes from my friends who use krill oil and support its benefits, but anecdotes are not strong evidence for me to give out to the public.
Prevent or ameliorate depression: Hey friend, if you are having serious issues, please please please treat the matter seriously and professionally with a certified figure. Here, I only offer my hypothesis for non-clinically diagnosed cases and as a potential preventive measure.
At the beginning of this Guide, I present a hypothetical formula I used to find for myself a ω-3 supplement to, hopefully, feel better after too many depression episodes.
There are both studies for and against this hypothesis of using w-3 as mood treatment. For instance of against, Jackson et al. 2012 published that, although after 12 weeks of supplementation with fish oil that met the formula, no effect was observed in terms of cognitive function nor mood in 18-35-year-old adults.
However, I think there was one criterion Jackson et al. did not meet in their study; EPA dose they used may have been under-dosed, because there are studies resulting in 1g of pure EPA supplementation (no DHA) may have effects in relieving clinically depressed patients (Peet & Horrobin 2002). Peet et al. (2002) also noted no effects when pure EPA dose exceeded 2g. Therefore, the amount of unopposed EPA (the amount of EPA in excess of DHA) can be set to 1g.
I will update the theoretical model as below. Among those presented supplements, two pills (serve) of MyProtein Omega 3 Plus will almost completely satisfy the below criteria. Omega 3 Plus was, in fact, my supplement choice this purpose in the past.

Supplements are just a piece of the puzzle. In fact, in the complete picture, when fish is included diet, the EPA & DHA concentration in the body system will shift. Being mentally stronger may come down to adequate nutrients, managed stress, and a combination of multiple life habits. Supplementation should be only treated as an insurance policy.

Thought for the Planet

A diet should nourish the human body, but also preserve future use for humanity descendants, and preserve the planet integrity. For this topic, I found an interesting collaborative work between EAT and Lancet commission. Their proposed good-for-human-and-planet-diet emphasizes fish, fruits & vegetables, legumes, whole grains, and nuts, after considering environmental consider parameters like greenhouse gas emission, fertilizer loading, land use, freshwater use, and extinction rate. Another interesting report is Knorr-WWF’s Future 50 Foods. The foods are mentioned for their nutrient density, culture, flavor, consumer familiarity, affordability, producer distribution, and environmental impacts in terms of climate change and land use.
In this section, I, as an Energy & Environmental Engineering student, want to apply some environmental thoughts to ω-3 source foods.
For global warming, sardine and herring are low greenhouse-gas, high protein, and ω-3 sources. The inclusion of these two small but ω-3 loaded fish may be the part of a futuristic healthy and sustainable food system. Salmon has higher GWP, but in a broad view, it has roughly the same average GWP as eggs and chicken. Therefore, enjoying bites of salmon once in while can give you a health boost without compromising Earth integrity.

TABLE 4. Global Warming Potential for ω-3 source food. (Data: Clune et al. 2016)

In terms of biodiversity, Atlantic Salmon, Atlantic mackerel, Atlantic herring, and European sardine are in "least concern" status in the Red List of Threatened Species (IUCN). However, Atlantic Salmon used to face a very high mortality rate in 1990, only to improve in 2008 after conservation attempts. Interestingly, WHO had considered the sustainability of fish supply in the big equation, when experts agreed on the value of 2g/d as the upper range of acceptable intake. Although a higher dose of 3g/day can farther reduce risks of heart diseases without evidence of adverse effects. (WHO 2008.).
Water consumption of walnut is rather high. Its production needs a high amount of rainfall, additional irrigation, and freshwater for later wastewater treatment. Not only walnut, but shelled nuts also have the second-highest freshwater withdrawals among food products (Ritchie & Roser 2020). So, if one of your values is a lower planetary impact, you may ponder on your selection and consumption of shelled nuts.

TABLE 5. Global average water footprint (1995-2005) for some food Among them walnut and linseed are sources of for ω-3. (Data: Mekonnen & Hoekstra 2010)

Ending note

Wow. That was such a bombardment of information. I appreciate that you are still reading till this point. My key take-away messages after all long reading will be: Walnut, chia seed, and flaxseed for ALA, at least two fish meal per week for EPA & DHA, or smart supplementation from plant-based oil.

Remember, Omega-3 is a small aspect of the holistic view of nutrition. When you eat foods, you are receiving nutrients and resources from the planet. Good nutrition fuels you to accomplish great things in life. Great accomplishment will nourish the beauty of the planet. It is a cycle of life. For my concluding remark, I invite you to develop a clear conscience about the well-being of the planet together with the well of your physical and mental being.  


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Clune, S., Crossin, E., Verghese, K. 2016. Systematic review of greenhouse gas emissions for different fresh food categories. Journal of Cleaner Production. Doi: 10.2016/j.jclepro.2016.04.082
EAT- Lancet Comission on Food, Planet, Health. 2019. Summary Report for Healthy Diets from Sustainable Food Systems. Available at: .pdf
Fineli. National Food Composition Database in Finland. Finnish Institute of Health and Welfare. Available at:
Finnish Food Authority (Ruokavirasto). N.d. Safe use of fish.
Gerster, H. 1998. Can adults adequately convert alpha-linolenic acid (18:3n-3) to eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3)? International Journal for vitamin and nutrition research, 68(3): 159-173.
Jackson, P. A. Deary, M. E. Reay, J. L. Scholey, A. B., Kennedy, D. O. No effect of 12 weeks’ supplementation with 1g DHA-rich or EPA-rich fish oil on cognitive function or mood in healthy young adults aged 18-35 years. British Journal of Nutrition. Vol. 107(8), 123201243. DOI: 10.1017/S000711451100403X
Mekonnen, M. M., Hoekstra, A. Y. 2011. The green, blue and grey water footprint of crops and derived crop products. Hydrology and Earth System Science. Vol 15, pg. 1577-1600. DOI: 10.5194/hess-15-1577-2011
Peet, M., Horrobin, D. F. 2002. A dose- ranging study of the effects of ethyl-eicosapentaenoate in patients with ongoing depression despite apparently adequate treatment with standard drugs. Archives of general psychiatry. Vol. 59(10), 913-919. DOI: 10.1001/archpsyc.59.10.913
Ritchie, H., Roser, M. 2020. Environmental impact of food production. Access on 20.04.2020. Available at:
Rodriguez-Leyva, D., Bassett, C. M. C., McCullough, R., Pierce, G. N. 2010. The cardiovascular effects of flaxseed and its omega-3 fatty acid, alpha-linolenic acid. Canadian Journal of Cardiology, vol.26 (9), 489-496. Doi: 10.1016/s0828-282x(10)70455-4
Starl, A. H., Crawford, M. A., Reifen R. 2008. Update on alpha-linolenic acid. Nutrition Reviews, Vol. 66(6), 326-322. Doi: 10.111/j.1753-4887.2008.00040.x
van Ginneken, V, J, T., Hellsper, J. P. F. G, de Visser, W., van Keulen, H., Brandenburg, W. A. 2011. Polyunsaturated fatty acids in various macroalgal species from north Atlantic and tropical seas. Lipids in Health and Disease, vol 10(104). Doi: 10.1186/1476-511X-10-104
WHO. 2018. Information Sheet: A healthy diet sustainably produced. Available at:
Williams, C. M., Burdge, G. 2006. Long-chain n-3 PUFA: plant v. marine sources. Proceedings of the Nutrition Society, vol. 65 (1), 45-50. Doi: 10.1079/PNS2005473
World Health Organization (WHO). 2008. Interim Summary of Conclusions and Dietary Recommendations on Total Fat & Fatty Acids. Joint FAO/WHO Expert Consultation on Fats and Fatty Acids in Human Nutrition, 10-14 November 2008, WHO, Geneva. Available at:

Credits for materials in my graphics
Logo. Global food web
Globe: Icon made by turkkub from

Visual 1. Planned ALA intake
Chia seed: made by vivali from File #: 207989909
Flaxseed: made by robu_s from File #: 137810758
Walnut: made by rea_molko from File #: 303530202

Visual 2. Food web
Algae: made by NokHoOkNoi from File #: 170014855
Fish: Icon made by Freepik from
Fish: Icon made by surange from
Microalgae: made by popaukropa from File #: 237553218

Visual 3. Supplements
Algae: Icon made by Twene from
Fish: Icon made by Freepik from
Shrimp: Icon made by Freepik from