I have heard that high dose folate and B12 during pregnancy contributes to babies being born on the spectrum. Thoughts?

A paper was published associating mothers with higher blood levels of folate and b12 are having babies on the spectrum.  Here are Dr. Lynch’s thoughts on the matter:

Association does not equal causation.

The researchers compared a number of variables between offspring who were typical and on the spectrum.

Other key factors that are worth mentioning:

• Women with children on the spectrum:
• 3 years older on average (28 vs 31)
• BMI was 2 points higher (26 vs 28)
• Gestational diabetes was a third higher (6% vs 9%)
• Diabetes type II was double the frequency (4% vs 8%)
• Preterm < 34 weeks delivery was more than double the frequency (9% vs 19%)

• Supplementation was self-reported. There is always variation in this as some women may say they were taking their prenatals 5x/week but they may have only taken it 2x/week and vice versa.
• High folate and high B12 levels aren't specific. They do not mention if it was folic acid, methylfolate or folinic acid. High doses of folic acid are definitely problematic. Do not use folic acid during pregnancy. Use folinic acid and methylfolate. If you cannot tolerate methylfolate, use folinic acid.
• The researchers failed to evaluate oxidative stress markers. High oxidative stress is associated with reduced methylation function. Reduced methylation function leads to higher B12 and folate levels.
• No dietary evaluations were done for either group. We have no idea what mothers were, or were not, eating.
• We don't know what medications either group was taking. SSRI's taken by pregnant women are a known trigger for increasing risk offspring on the spectrum. Tylenol during pregnancy is also a risk factor.
• We don't know anything about vaccinations or illnesses during pregnancy in either group.

Likely, these women were using inferior forms of folate and B12.†

Action Steps:

1. Supplementation with active forms of folate, namely folinic acid and methylfolate, are highly recommended during pregnancy. Do not use folic acid.†
2. Supplementation with active forms of B12, namely methylcobalamin and adenosylcobalamin, are highly recommended during pregnancy. Do not use cyanocobalamin.†
3. Learn more about Folic acid and Pregnancy. Watch Dr. Lynch’s presentation on YouTube: https://www.youtube.com/watch?v=tnVRv0zGsFY

Both folate and vitamin B12 are water soluble. Excess amounts are efficiently eliminated via the urine.†

Source:

https://onlinelibrary.wiley.com/doi/10.1111/ppe.12414

†These statements have not been evaluated by the Food and Drug Administration (FDA). This product is not intended to diagnose, treat, cure, or prevent any disease.