Sign Up
Conception Pregnancy Mar 24, 2019
10 Minutes

The Supplement Series: DHA: A tool in the fight against pregnancy complications and neurological issues in kids

This article looks at the supplement DHA and why it is crucial to take during pregnancy. We look at it’s power against chronic inflammation, why that is such a crucial thing to fight particularly during pregnancy and how it can be a powerful tool for your baby’s brain development (amongst many other things). Finally we look at how and when you should consider taking it.

One of the biggest things to come out of research in the last few decades is the recognition that one of the root causes of many issues we are experiencing more these days is chronic inflammation. Something that our modern lifestyles are very good at creating within us – often without us even noticing…

Click here for much more on this (where it comes from/its effects etc), but specifically for our purposes, it has been linked to issues like preterm birth and also neurological issues developing in older kids which are on the rise in our modern times like anxiety, depression and ADHD.

So – in short it is not something we want a lot of.

This is all very well and good of course, but the really important question is: what can we actually do about it?

Here is some good news!

The Journey is all about using the latest cutting edge research to understand what are the things actually in our control, things we can do which can potentially help reduce our risks. Things that are backed by science.

Well – today there is another to add to the fight!

Polyunsaturated Fatty Acids and specifically DHA:

Today’s article is a quick look at:

  • what they are

  • when and how they build in a small person’s body

  • how they work and what the science says

  • and most crucially, how you can best support them in your/your child’s body.

So, what are they and where can we find them?

One type of Polyunsaturated Fatty Acids you may have heard of are Omega 3’s. From a dietary perspective, they are found in fish and shellfish. These are known as long chain: EPA and DHA are examples. They are also found and in things like flaxseed. These are short chain: ALA is an example of this.

What should you care about?

Research suggests that although short chain have their benefits, it is the long chain that you really want to focus on. So think DHA and EPA. Particularly when it comes to inflammation and associated issues around growing babies and children.

Why should you care about this?

Here’s what the research is suggesting:

For pregnancy and risk of preterm birth:

There has been a lot of work done looking at causes of pre term birth. Although of course there are usually a variety of causes, with infection often a principal cause, one of the features commonly reported once again is inflammation:

To quote just one study:

‘we speculate that pregnancies at risk for eTB (early term birth) include a disproportionate number with inflammation’ (1) – click here for more.

One shocking statistic I read was that when it comes to preterm deliveries in the US we are now at a rate of 1/8 births being preterm – which is high. In fact, the US now has the highest rate of preterm (< 37 weeks) births of any of the other developed countries. (1)

There has been research emerging supporting the use specifically of DHA as a contributor to prevention of pre-term birth. In fact, DHA status in pregnancy was first linked to longer gestation, higher birth weight and less PTB (pre-term birth) by early studies of Olsen and collaborators who found much lower rates of preterm birth and low birth weights on the Faroe Islands, where there was much more consumption of Omega 3 rich seafood. (2)

Further to this, three trials looking at omega-3 long chain polyunsaturated fatty acid supplementation ‘all reported a reduction in early pre-term birth’ (1)

What is also interesting is that in the US, on average DHA intake is lower than in other Western Populations – the only other that is very low on average is India (being mainly vegetable based and therefore low in DHA which comes principally from fish) which incidentally has the highest rates worldwide of pre term birth at 24%. (1) In fact pre term births have gone up in the last twenty years in almost all countries (3)

Also interesting is the fact that the statistics show that in the US the average woman consumes around 60mg/day of DHA and most do not take a supplement. Despite the fact that the Academy of Nutrition and Dietics recommends approx 500mg/day of DHA in the prenatal diet (with a suggestion of 2x servings a week of low-mercury fish/wk). (3)

Finally a new study from Denmark demonstrated a 10 fold increase in risk for early pre term birth in women with a low omega 3 fatty acid blood levels. (3)

So how exactly does this work?

The theory, once again, surrounds inflammation: ‘the potential of DHA to reduce early pre term birth (ePTB) is plausibly linked to its role in reducing inflammation, a final pathway for spontaneous ePTB.’ (1)

The interesting thing about DHA is that it has ‘plausible cellular effects that could modify the onset or change the timing of inflammation’ and this has been demonstrated in both human and animal studies. (1)

That brings us to to some of the other benefits:

There has been a lot of work around the benefits of fatty acids on neurodevelopment, cognitive ability and even the role it plays in anxiety, depression and ADHD.

Fundamentally DHA is a structural constituent of membranes within the central nervous system. So, not having enough is not going to be good.

Here’s how it build’s in a baby:

It’s accumulation actually starts to rapidly in the last trimester of pregnancy and continues at very high rates up to the end of the second year of life (4) and ‘accumulating data indicate that DHA may have effects on the brain in infancy’ with the suggesting that potential effects continue to play a role during childhood and adult life ‘suggesting a role of DHA in cognitive decline and in relation to major psychiatric disorders’.

This initial transfer is via the placenta and the mother and then continues on via breastfeeding. Yet another reason to prioritise breastfeeding wherever you possibly can is the fact that ‘studies in infant brains have shown around 25% higher mean levels of DHA of breastfed babies vs formula fed’. (4)

To be clear, when it comes to cognitive functionality the studies are absolutely not slam dunk and conclusive with varying results. However, one MRI study (which is obviously slightly less subjective) did show that DHA supplementation was associated with an increased activation of the prefrontal cortex and better reaction time during sustained attention in healthy boys.’ (4)

Other trials have shown benefits on mood, attention (specifically thinking around ADHD) and even in depression:

When it comes back to anxiety and depression, once again the thinking is the role that this plays specifically in modulating inflammation. Click here to read much more on this – or for a really phenomenal read check out Eric Bullmore’s ‘Inflamed Mind’ – one of the best books I’ve read in a long time which backs this theory up, supporting the role that reducing inflammation can play.

’Cross national studies indicate that higher intake of fish/seafood is correlated with lower lifetime prevelance rates of…depression. In fact, depression may present with an increased production of pro-inflammatory cytokines…and Omega 3 long chain fatty acids have in randomised controlled studies been shown to reduce both.’ (4)

ADHD and Omega 3 have been looked at quite a bit:

Once again, empirically – alas – there is no slam dunk. However, it is tricky to evaluate in many cases and there is enough to suggest that it can potentially play a positive role:

’the findings support the suggestion that prenatal DHA may positively affect infant’s attention and regulation of state’ (5) and one trial showed that infants from mothers who were supplemented maintained a consistent level of sustained attention… while sustained attention dropped off across the first year in infants from non-supplemented mothers…and this specific profile has been previously reported to be associated with higher preschool vocabulary and intelligence scores at 4yrs.’ (5)

On the flip side: research has shown that ‘children with ADHD and ASD had low levels of EPA and DHA and… these correlated significantly with symptoms.’ (6) This is not just one study either – a recent meta analysis of nine studies found that children with ADHD had lower overall blood [Omega 3] polyunsaturated fatty acid levels than controls, particularly DHA. (6)

So: again the message seems to be: low EPA/DHA (Omega 3s) = not good.

Once again – it continues to be linked back to inflammation and oxidative stress and that ‘despite limitiations, the results seem to highlight the beneficial role of polyunsaturated fatty acids in [some] neuropsychiatric disorders…the available evidence also suggests that the detection and treatment of deficiency early….may exert the greatest protection and reduction in severity of the symptoms.’ (6)

So – a diet full of good fish is great from that perspective… however….

The source and amount is key:

Of course we all know the risks on the other side related to mercury exposure from consumption of too much fish (also known as methylmercury). I was someone who was wary of too much during my pregnancy, which is just one reason why pregnant women tend to actually consume less fish during pregnancy (that plus the fact that morning sickness doesnt exactly have you reaching for the fish pie).

So – what can you do?

Well first and foremost how much do you actually need? Many of the studied referenced used around 500-800 mg/day (although it went in some cases higher than that to 1000mg/day) – the Academy of Nutrition and Dietics recommends approx 500mg/day of DHA in the prenatal diet. So that is a good starting point (if in doubt however always ask your doctor).

How do you get there?

As a sceptic on supplements (largely because they are unregulated and full of pitfalls if you dont get the right brand) I personally always prefer going down the food route if you can.

Question is – how much fish do you have to eat to get to that level?

Well: according to (there really is a website for everything!) a serving size of omega 3 rich fish is around 3.5oz cooked. Two servings of that size according to them should = between 650mg up to 3,000. Two servings per week are recommended.

Two things to bear in mind:

Mercury in fish is a problem and absolutely should be considered – click here for more. The trouble is that it doesnt break down and in fact bioaccumulates (ie if a big fish eats a smaller one then that big fish has its own mercury plus the mercury from the smaller one) so you want to focus on the smaller fish like sardines, anchovies, mackerel etc. Basically anything lower down the food chain and avoid the big ones like Swordfish or too much Tuna. You also want to go for wild (as sadly farming these days means lots of antibiotics and other undesirables used) and of course if you are pregnant always go for cooked vs raw.

The second is not everyone likes fish – especially kids. So – supplements in this case can be very useful. I would go for a full Omega 3 supplement as you have EPA included in there too as well as the DHA. Check the amount per serving though (you want at least 500mg DHA) and make sure that the fish they use is wild and from fish lower down the food chain – the good brands will flag this up so if its not explicitly mentioned on the packet avoid it.

Bottom line: although the results (as they rarely are) are not slam dunk conclusive – there is enough here to suggest that focusing on omega 3 and specifically DHA is a solid plan in order to reduce risks around pre-term birth and to support healthy brain and mental development for your child. Incorporating two servings of wild fish lower down the food chain every week seems eminently sensible and if you dont fancy that – it is worth – particularly during pregnancy – investing in a good brand Omega 3 supplement. Worth at least discussing with your doctor.


(1) CARLSON S, HAJEWSKI B, VALENTINE J, WEINER C, BUHIMSCHI S: Assesement of DHA on reducing early preterm birth: the ADORE randomised controlled trial protocol. BMC Pregnancy and Childbirth . Feb 2017.

(2) CARLSON S, COLOMBO J, GAJEWSKI J, SHADDY D: DHA supplementation and pregnancy outcomes. American Journal of Clinical Nutrition. Feb 2013

(3) JACKSON H, HARRIS W: A Prenatal DHA test to help identify women at increased risk for early preterm birth: A proposal: MDPI Nutrients: Dec: 10(12) 1933

4) AGOSTINI C, NOBILE M, BRAMBILLA P: The Role of Omega-3 Fatty Acids in Developmental Psychopathology: A systematic review on early psychosis, autism, and ADHD. MDPI Nutrients: 2017 Dec: 18(12)

(5) TONG L, XIONG X, TAN H: Attention-Deficit/Hyperactivity Disorder and Lifestyle-Related Behaviours in Children: PLoS One: 2016: 11(9)

(6) PARLETTA N, NIYONSENGA T, DUFF J: Omega-3 and Omega-6 Polyunsaturated Fatty Acid Levels and Correlations with Symptoms in Children with Attention Deficit Hyperactivity Disorder, Autistic Spectrum Disorder and Typically Developing Controls: PLoS One: 2016: 11(5)


This article is for informational purposes only. This article is not, nor is it intended to be, a substitute for professional medical advice, diagnosis, or treatment and should never be relied upon for specific medical advice. The information on this website has been developed following years of personal research and from referenced and sourced medical research. Before making any changes we strongly recommend you consult a healthcare professional before you begin.

The Journey Logo

Copyright © 2023

Welcome to The Journey

Each month we will be giving away a curated box of goodies to suit the individual stage of your Journey, worth £100. To enter the draw and join us, enter your details below. Winner announced at the end of the month.


Welcome to The Journey

Each month we will be giving away a curated box of goodies to suit the individual stage of your Journey, worth £100. To enter the draw and join us, enter your details below. Winner announced at the end of the month.


Next on your journey?