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by Daphne Lambert

DHA & the plant based diet


So what is DHA?

Docosahexainoic acid  (DHA) is a long chain fatty acid derivative of alpha linolenic acid otherwise known as omega 3.


Omega 3 is one of the two essential fatty acids, the other one being omega 6, that your body is unable to make so you must get them from your diet.


Why is DHA so important

DHA is a component of brains particularly the synaptic junction between nerve cells. Low DHA has been linked to depression, memory loss, alzheimers, ADHD, anti-social behaviour and schizophrenia.

DHA is central to the development of the human cortex and necessary for sustained attention, decision making and problem solving


DHA plays a “unique and indispensable role” in the “neural signaling essential for higher intelligence.” —Simon Dyall PhD, Lipid Research Scientist Bournemouth University, UK

DHA is important for a baby’s brain and visual development especially during a women’s last trimester of pregnancy.
DHA has an anti-inflammatory effect and for example may improve conditions like rheumatoid arthritis.

Dietary ALA can be converted to SDA and then EPA & DHA. They can also be found preformed in certain foods.

Omega 3 fatty acids

Alpha Linolenic Acid     found in linseed, hempseed, chia seed, green leafy
(ALA)                             vegetables especially purslane

Stearidonic Acid (SDA)  hempseed, animal products

Eicosapentaenoic acid     animal products particularly oily fish and brain
(EPA)                              algae (processed)                

Docosahexaenoic acid     animal products particularly oily fish and brain
(DHA)                            algae (processed)


Whilst it is easy to get enough ALA on a plant based diet, plant foods (with the exception of algae which I will mention at the end) contain no EPA & DHA. Conversion to these longer chain fatty acids can be minimal and in some cases nonexistent.


Hinderance to conversion
An omega 6 to omega 3 ratio that is too high will hinder the conversion of ALA to DHA.
Pre-industrial diet had an omega 3 ratio between 4: 1 & 1: 4 today the ratio is closer to 20: 1

Processed fats and trans fatty acids and the processed foods that contain them

Lack of co-factors especially vitamin C, B3 & B6 as well as magnesium and zinc

What to do
The most important thing you can do is try and balance your omega 6 to omega 3 ratio
limit the following oils that are high in omega 6 sunflower (71%) corn oil (57%) soybean (54%) cotton seed (54%) sesame (42%)

Add plenty of hemp seeds to your diet as well as linseed (both as oil and seed)

Eliminate altered oils and fats – nearly all processed foods/fast foods are made with refined oils such as soybean and sunflower

Eat plenty of green leafy vegetables

Fortunately there are vegan friendly DHA supplements made from algae
You might think that you could just eat seaweed  but it seems this is too unreliable as the DHA in these fibrous foods may not be bio-available. Most vegan DHA supplements are made from micro-algae

I recommend:

opti 3 from vegetology

omega 3 DHA from Nothing Fishy



Dietary omega-6 fatty acid lowering increases bioavailability of omega-3 polyunsaturated fatty acids in human plasma lipid pools. Taha AY et al

Long-chain omega-3 fatty acids and the brain: a review of the independent and shared effects of EPA, DPA and DHA. Simon C Dyall



A Comprehensive Review of Chemistry, Sources and Bioavailability of Omega-3 Fatty Acids

Mateusz Cholewski Monika Tomczykowa Michael Tomczyk

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