I’ve had some (panicked) questions about the recent articles on folic acid supplementation during pregnancy and increased risk of autism. Let’s chat science:
1. This study is what is called an Observational Study. Do these types of studies have their merits? Absolutely. Do they establish causation? Absolutely NOT. This study looked at blood levels of folate and B12 in newborns 24-72 hours after birth, and then the development of ASD later in life. A correlation was established. Correlation – just like how eating ice cream increases your risk of being bitten by a shark.
“LOGIC”: eating ice cream happens more in the summer –> the summer equals more people swimming in the ocean –> more people swimming in the ocean increases the risk of shark attacks, therefore eating ice cream –> increased risk of shark attack. Absurd.
Now it’s important to not simply throw out a study because it’s correlational. Correlational studies are the jumping off point for mechanistic studies. But, we can’t make recommendations, especially dramatic ones, on correlation.
2. No mechanism is established. But you know what we do have a mechanism for? Folate deficiency and neural tube defects. The neural tube is the part of the embryo that turns into the spine. It closes at 3 weeks post-conception, and REQUIRES folate to do so successfully. There is a known, causal mechanism for folate deficiency and NTDs like spina bifida. And the fact that it is required so early in pregnancy, before many women know they’re pregnant, shows how important it is to be taking folate (or eating a TON of leafy greens and chicken livers) prior to conceiving.
3. Population. Direct quote from the study:
“Data are from the Boston Birth Cohort…that recruited low-income urban, primarily minority mother-offspring pairs…followed them from birth through childhood…”
There are many confounding factors in that statement alone. For example, income is the number one determinant of health. This shows that it is important to analyze the actual study, instead of just reading a headline.
4. Folate vs. Folic Acid. Have you noticed that I’ve only used the word “folate” thus far? That’s because FOLATE is the food-based version of this important B vitamin. It’s the one the body needs and recognizes as usable. Folic Acid is a synthetic form of folate – it is not the same thing, and in some cases (usually with genetic anomalies) it can cause problems. Most people uses these 2 terms interchangeably but I cannot stress the importance of recognizing the difference. Finding a pre-natal supplement that contains FOLATE is challenging, but there are a few out there. You want to look for something that says “folate” or “active folate” or “methylated folate”. My favourite is Designs for Health, in combination with lots of leafy greens and regular liver consumption.
5. More isn’t better, it’s just more. As with all supplementation, more isn’t better. Follow your practitioner’s recommendations for the amount of folate to consume (just make sure it’s folate, not folic acid, and make sure that if your practitioner wants you to stop supplementing, they read the STUDY not the news article…otherwise get a second opinion.) Better yet, get most of it from your food. Leafy greens and chicken livers are your best sources!
6. Nutrients do not work in isolation. High levels of plasma folate and B12 indicate a metabolic issue – either stemming from a genetic anomaly (like the MTHFR mutation) or more often, other nutrient deficiencies. A diet high in all the nutrients (as in, not just from a pre-natal, but from consuming lots of vegetables, fruit, liver, meat, fish, eggs and quality fats) is required for all systems to function properly. Check out my free handout for a nutrient dense diet for fertility and pregnancy.
7. The media and nutrition. This is a post in and of itself, but to sum up quickly – the media should be ashamed of themselves for the way they create fear through headlines. No one ever reads the study before creating a shocking, and terrifying title. Case in point this study – the study authors conclusion:
“In this urban low-income minority birth cohort, we observed an elevated risk of ASD associated with high maternal plasma folate levels (>59 nmol/L), which far exceeds the excess cutoff suggested by the WHO (>45.3 nmol/L); however reported maternal vitamin supplementation was protective. Excess maternal vitamin B12 (>600 pmol/L) in pregnancy was also shown to be associated with greater ASD risk in offspring. The risk of ASD was highest if mothers had both excess prenatal folate and vitamin B12 levels. Our findings warrant additional investigation and highlight the need to identify optimum prenatal folate and vitamin B12 levels that maximize health benefits, at the same time minimize the risk of excess and its associated adverse consequences such as ASD.”
An interview with the study authors states this even more emphatically:
“Our work is very consistent with previous work showing that supplementation is critical to maternal health and child development and health, so at this point the recommendation is definitely to continue supplementation. What this study finds is that while maintaining adequate levels of folate is important, extreme levels may be harmful.”
What does all that mean?
Continue supplementing during pregnancy!
In summary, please do not freak out if you’ve been taking prenatals thus far. They are incredibly important (and this is coming from someone who prefers food over supplements most of the time!). Ideally switch to a version that contains folate, the active form of the nutrient recognized by the body. Keep the diet incredibly rich in nutrients by focusing on lots of leafy greens, quality meat & organ meats, egg yolks, fish, grass-fed dairy (if tolerated), bone broth and probiotic-rich foods (like sauerkraut & kombucha).