Your Brain Is Fat: It Needs To Stay That Way

Are you doing your brain a disservice if you miss out on essential fatty acids from fish? Or can plant-based sources help?


9 Minutes Read

A pair of hands hold a brain The brain is our most complex organ by far - Media Credit: Adobe

You have a big fat brain. Accounting for nearly 60 percent1 of the miraculous, gelatinous blob sitting in our heads, this fat is rich in omega-3 fatty acids2—essential in the diet and critical for brain development and functioning. So are you getting enough?

Thanks to vocal influencers like Miley Cyrus, Anne Hathaway, and Tim Shieff ditching their plant-based ways overnight and claiming near-instant positive transformation brought about by the omega oils in fish, you may be starting to wonder whether you too are missing out on these essential fats, and doing your brain a disservice.

Complicated and fascinating

The truth, much like your brain itself, is complicated, fascinating, and worth understanding.

Less than 400 years ago, the English philosopher Henry More3 summed up the feeling of the time, dismissing the brain as having ‘no more capacity for thought4 than a cake of suet or a bowl of curds’. Yet, within the same century, the idea that the brain may have a much more critical function5 than we had given it credit for began to gain traction. 

Today, our difference in understanding is breathtakingly stark, and we know our brains to be – by some margin – the most complex organ6 in our bodies, defining7 our personalities, health and more. No longer a shockingly disregarded lump between our ears, the brain is now considered the most complex thing yet discovered8 in our universe; not bad for a bowl of curds.

The human brain
Adobe Your brain is complicated, fascinating, and worth understanding

Billions of nerve cells

Weighing about as much as 3-4 blocks of tofu, your brain comes equipped with one hundred billion nerve cells9 all connected via mind-bogglingly tiny structures called synapses.

In the time it’s taken you to read this sentence, your brain will have formed seven million new connections, a trick it’ll continue to pull off every second of your life. Contrary to popular belief, you don’t only use 10 percent of your brain10 either—you use virtually every part of it, and most of these parts are active almost all of the time.

What your brain needs

The least you can do in return for all of this thankless effort is to give your brain what it needs to thrive, and for you to have the best opportunity for long-term good health, those omega-3 fatty acids are critical11. The three varieties of these wonder molecules are alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). 

Not all fatty acids are created equal. With DHA comprising over 90 percent of the total omega-3 fatty acids in your brain and up to 25 percent of the total fat content, we have evolved alongside12 this ancient nutrient, discovering that it provides optimal conditions for a wide range of cell membrane functions and is essential for brain13 and eye14 development.

ALA is found in plant oils, while EPA and DHA are typical in fish such as salmon and tuna. Yet, we will see that the answer to where we can get all the DHA we need on a plant-based diet is a surprisingly simple one, thankfully since low levels of DHA can have seriously detrimental effects.

Human Brain and nerve cell anatomy in details.
Adobe The brain has one hundred billion nerve cells

Lower DHA levels

Found primarily15 in the famous ‘grey matter’, lower levels of DHA are linked to neurodevelopmental disorders such as ADHD16 (attention-deficit/hyperactivity disorder) and neurodegenerative diseases such as Alzheimer’s17. Low DHA in expectant mothers also increases the risk of poor neural development18 in children and is a common cause of infertility through compromised sperm health19.

Conversely, DHA and EPA are proven to decrease levels of arterial wall-thickening triglycerides in the blood, so reducing the risk of heart disease.

Risk reduction

Adequate levels of DHA are linked to reductions in risk for:

1. Heart disease20

2. Dementia21

3. Depression22

4. Premature birth23

5. Colorectal, breast and prostate cancer24.

DHA can also fight inflammation25, help with muscle damage26 and eye conditions27, lower blood pressure28 and improve blood flow29

DHA and fish?

DHA is increasingly well-understood with a wide range of wellbeing and clinical applications, yet this doesn’t mean those vegan influencers who threw in the plant-based towel and reached for a fish were onto something.

While omega-3 levels can build up relatively quickly, it still takes anywhere from six weeks to six months30 for any significant change in mood, ‘brain fog’ or other symptoms to become apparent. Anyone reporting quick fixes and overnight success should be met with skepticism.

When it comes to ensuring we are getting enough omega-3 into our bodies to reap the positive health benefits, again, not all sources are created equal. Of the three main omega-3 molecules, ALA is an ‘essential’ fatty acid, meaning our bodies are unable to make it31, and we must obtain it from our food.

Plant-based omega-3

While there are plenty of great plant sources of omega-332 fatty acids – including chia seeds, Brussels sprouts, walnuts, and flaxseed – we have to convert the ALA we consume into EPA and DHA. With only a limited supply of enzymes available in all of us to do this job, a vanishingly small amount is converted33. 90 percent or more is metabolised and processed in a slow and inefficient process34 affected by genetics, sex, age and diet.

Flaxseed and other omega-3 foods are tasty and nutritious elements of any plant-based diet, yet while they can offer an ALA boost, they should only be considered a backup and not primary sources of omega-3 due to this low conversion rate. Notably, while ALA intake is similar in vegetarians and non-vegetarians, EPA and DHA are low in vegetarians and virtually absent35 in vegans.

Another wrinkle is that omega-3 fatty acids aren’t the only game in town; omega-6, or linoleic acid, is an essential fatty acid. Pro-inflammatory36 in contrast to the anti-inflammatory omega-3, a thousand-fold increase37 in consumption of soybean oil (50-60 percent linoleic acid) over the last century means dietary intake of omega-6 has ballooned. 


The American Heart Association38 has advised omega-6 fatty acids are safe, even beneficial for the heart and circulation, and diets including balanced amounts39 of omega-3 and omega-6 are the best way forward to reduce risk and inflammation. Furthermore, the Vegan Society touts the importance of this balance, noting that eating a lot of linoleic acid can upset the ALA to EPA and DHA ratio.

The situation is this: our big fat brains need omega-3 in the form of DHA, and our bodies can’t make it. Our conversion rate for wrangling ALA into DHA and EPA is embarrassingly low, and our intake of omega-6 can make this conversion rate even worse.

Fish oil capsules
Adobe Some people may fear they need fish oil- but there are plant-based alternatives

Eating fish?

Perhaps – for a fleeting, terrifying moment – we may wonder whether eating DHA and EPA-rich oily fish40 or taking omega-3 fish-oil supplements are essential to ensure we dodge a range of potentially life-deranging health issues. 

Reassuringly, when we turn our long-honed brains on the problem of accessing these tricky yet essential fatty acids, we realise that however true it is that accessing omega-3 via the marine food chain had substantive impacts on the survival and brain health of our distant ancestors41, unlike them, we don’t need to eat fish—we need to eat like fish.

Since our fishy cousins in the wild build up their own reserves by consuming microalgae (or eating smaller fish who previously consumed microalgae), we now have the option of going straight to the source42 for a safe, natural and efficient solution to our needs. Comparable to oily fish in regard to the nutritional availability of the EPA and DHA we crave, algal oil43 is now staking its claim as the plant-based source of choice for these essential fatty acids. 

Algae supplements

Sourcing from algae supplements comes with significant benefits for the environment44 too, sidestepping the rampant overfishing devastating ocean food chains and driving the climate crisis, and for avoiding the toxic effect of mercury accumulated45 in fish bodies.

The algae already being used46 for omega-3 fatty acid production are widely dispersed throughout our oceans, and the biotechnological process now in use will be further refined and improved as we search the high seas and discover new species with fast growth rates, high biomass content, and oil accumulating capabilities. Nor is this some distant great hope of the future – a vast and growing range of omega-3 vegan algal supplements are available right now every health need and price point.  

In conclusion, pay attention to your linoleic acid intake and keep your omega ratio balanced with simple fixes like ditching sunflower, corn, or sesame oils, and reducing the amount of sunflower and pumpkin seeds you eat, and find a a high-quality, mercury-free and sustainable algal supplement to suit you. For an additional, lower-level omega-3 boost—alongside a bounty of vitamins and minerals such as magnesium, B12 and calcium—throw some tasty seaweed into your diet too.

Algae is the future

We’ve come a very long way from our prehistoric predecessors scooping up marine life. Unfortunately, we still have a long way to travel from vegan influencers making spurious claims about eating fish causing radically improved brain function or leading to them ejaculating for the first time in months

Let them enjoy their placebo effect. You are the proud owner of the most complex thing in the universe; a brain freshly-armed with knowledge and the opportunity to do the right thing, feeding it what it needs while harming no animals in the process. 

So here’s to our algae-based future. You have a big, fat, beautiful brain. Use it, feed it well and keep it that way.  



*This article is sponsored by HEIGHTS.

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