According to research reviewed by Gram, pregnant women who drank alcohol had lower vitamin B6 levels (3.5 vs 4.6 micrograms per liter) than abstainers. Higher maternal betaine levels were also linked to larger head size and fewer physical differences in babies at nine months, though these links were weak.
Drinking alcohol during pregnancy can harm a developing baby, but nutrients in the mother’s body may play a role in how children grow. According to research reviewed by Gram, researchers in South Africa measured nutrients in pregnant women’s blood and then checked their babies’ growth and development at nine months old. Women who drank alcohol had lower levels of vitamin B6 than women who did not drink. Higher levels of a nutrient called betaine were linked to larger head size and fewer signs of physical differences in babies. Folate, another B vitamin, was linked to better social and emotional scores. These links were modest, and the study cannot prove cause and effect. Still, the findings suggest that a mother’s nutrition during pregnancy may matter for her child’s development, even when alcohol is part of the picture.
Key Statistics
A 2026 South African cohort study found that pregnant women who drank alcohol had significantly lower vitamin B6 levels (3.5 micrograms per liter) than women who abstained (4.6 micrograms per liter).
In a 2026 study of mothers and children in South Africa, higher maternal betaine levels during pregnancy were weakly linked to larger infant head size (r = 0.18) and fewer signs of physical differences at nine months.
A 2026 South African cohort study reported that most children were between the 25th and 40th percentile for height, weight, and head size at nine months, regardless of prenatal alcohol exposure.
The Quick Take
- What they studied: Researchers asked whether certain nutrients in a pregnant woman’s blood, and certain genetic variations in mothers and children, were linked to how babies grew and developed when the mother had been exposed to alcohol before birth.
- Who participated: Pregnant women in South Africa and their children, followed up at nine months of age. The exact number of participants was not specified in the summary provided.
- Key finding: Pregnant women who drank alcohol had lower vitamin B6 levels (3.5 micrograms per liter) than women who did not drink (4.6 micrograms per liter). Babies generally fell between the 25th and 40th percentile for height, weight, and head size, whether or not they were exposed to alcohol. Betaine levels were linked to head size and fewer physical differences, but these links were weak.
- What it means for you: Eating a varied diet rich in B vitamins and betaine-containing foods during pregnancy is a sensible habit. This study does not prove that these nutrients protect babies from alcohol’s effects, and the safest choice during pregnancy is to avoid alcohol completely. Talk with a healthcare provider about your nutrition needs.
The Research Details
The researchers collected blood samples from pregnant women and measured several nutrients linked to a body process called one-carbon metabolism. This process helps cells make new genetic material and supports healthy brain and body development. The nutrients measured included choline, betaine, folate, vitamin B6, and homocysteine, along with related compounds such as dimethylglycine (DMG).
The researchers also looked at specific genetic variations, called single nucleotide polymorphisms (SNPs), in both mothers and children. These are small differences in genetic code that can affect how the body handles nutrients. The women were grouped by whether they drank alcohol during pregnancy, so the team could compare nutrient levels between drinkers and non-drinkers.
When the children reached nine months old, the researchers measured their height, weight, head size, and physical features. They also gave a developmental screening that looked at social and emotional skills. Statistical models were then used to see whether nutrient levels were connected to these child outcomes, and whether the connection changed depending on alcohol exposure.
This type of study follows real mothers and children over time and measures both what the mother’s body contained and how the child developed. That makes it possible to spot patterns that a lab experiment alone could miss. Because the children were studied at nine months, the findings give an early look at development, although they cannot show what happens later in childhood.
The study measured nutrients directly from blood samples and included a comparison group of women who did not drink, which strengthens the comparison. However, the summary provided does not report the total number of participants, and the links found were mostly weak. Many of the statistical tests did not reach the usual threshold for strong evidence. Observational studies like this one can show that factors are connected, but they cannot prove that one causes the other. Readers should view these results as early clues rather than firm conclusions.
What the Results Show
Women who drank alcohol during pregnancy had clearly lower vitamin B6 levels than women who abstained. For most other nutrients, including choline, betaine, dimethylglycine, folate, and homocysteine, there was no difference between drinkers and non-drinkers. Vitamin B6 plays a role in many body processes, including brain chemistry, so this difference is worth noting for future research.
On average, the children were between the 25th and 40th percentile for height, weight, and head size. This was true whether or not they had been exposed to alcohol. Being in this range means that, on average, these children were somewhat smaller than the middle of the typical range. This is a notable pattern, though the study does not explain why it occurred.
Higher betaine levels in mothers were linked to larger head size in children, with a weak positive connection (r = 0.18). Betaine levels were also linked to fewer signs of physical differences, which the researchers measured with a dysmorphology score. Betaine was not significantly changed by alcohol exposure in the combined analysis, but betaine itself had a clear relationship with child outcomes. Betaine is found in foods such as beets, spinach, quinoa, and eggs.
Higher folate levels were linked to better social and emotional scores in children, though again the connection was weak (r = 0.17). A ratio between betaine and DMG was also linked to better social and emotional scores. Taken together, these results suggest that the balance of several nutrients may matter as much as any single nutrient.
Few genetic variations in mothers or children were connected to the nutrient measurements. Average head size and physical difference scores were nearly identical across different genetic groups, which suggests that these specific genetic patterns did not strongly shape early growth in this group. The statistical test for an interaction between betaine and alcohol was not significant. This means the study did not find clear evidence that betaine protects babies differently depending on whether their mothers drank.
Earlier research has linked folate and other B vitamins to healthy brain and nervous system development in babies, and has shown that alcohol can disrupt how the body uses these nutrients. This study adds to that picture by focusing on betaine and on a South African population, which has been studied less often than populations in North America and Europe. The findings fit with the idea that nutrition during pregnancy can influence how alcohol affects a child, but more research is needed before firm conclusions can be drawn.
The study looked at children only up to nine months of age, so it cannot show whether these patterns last into later childhood. The connections between nutrients and child outcomes were weak, which means they explain only a small part of the differences between children. Because the study was observational, other factors such as diet quality, income, smoking, other substances, or access to healthcare could have influenced the results. The summary also does not report how many women and children took part, which makes it harder to judge how reliable the findings are. Finally, these results come from one region of South Africa and may not apply to every population.
The Bottom Line
Pregnant women should avoid alcohol completely, since no amount has been proven safe during pregnancy (high confidence). Eating a varied diet with foods rich in B vitamins, folate, and betaine is a reasonable, low-risk habit that supports general health during pregnancy (moderate confidence). Taking specific supplements based on this study alone is not recommended, because the findings are early and the links were weak (low confidence). Discuss any supplement plans with a healthcare provider.
Pregnant women, people planning a pregnancy, midwives, nurses, doctors, and public health workers may find these findings useful. Researchers studying fetal alcohol spectrum disorders and early nutrition will also be interested. People who are not pregnant and not planning pregnancy will find less direct value, though the findings may still support a general habit of eating a balanced diet.
Nutrition during pregnancy affects a baby’s development before birth, so the window for influence is the pregnancy itself. Improvements in a mother’s diet can take several weeks to show up in blood nutrient levels. Any effects on a child’s growth or development would be visible over months to years, and this study only followed children to nine months, so long-term benefits remain unknown.
Frequently Asked Questions
Does vitamin B6 drop in pregnant women who drink alcohol?
Research reviewed by Gram found that pregnant women who drank alcohol had lower vitamin B6 levels, averaging 3.5 micrograms per liter, compared with 4.6 micrograms per liter in women who abstained. The study was observational, so it shows a link rather than proving alcohol directly causes the drop.
What foods contain betaine that may help during pregnancy?
Betaine is found in foods such as beets, spinach, quinoa, and eggs. A South African cohort study linked higher maternal betaine to larger infant head size, though the connection was weak. Eating these foods is a healthy habit, but they should not replace medical advice.
Is there a safe amount of alcohol during pregnancy?
No amount of alcohol has been proven safe during pregnancy. Nutrients such as betaine and folate may support development, but research shows they do not cancel out alcohol’s risks. Avoiding alcohol completely is the most reliable way to protect a developing baby.
Can good nutrition during pregnancy offset the effects of prenatal alcohol exposure?
This study did not find that betaine changed the effects of alcohol in a significant way. Researchers observed links between nutrients and child growth, but these links were modest. Good nutrition supports development, yet it cannot be relied on to fully counteract alcohol exposure.
Want to Apply This Research?
- Log daily servings of B-vitamin and betaine-rich foods, such as leafy greens, beets, eggs, legumes, and whole grains, and track weekly totals. Also log any alcohol intake as a separate, clearly marked entry with a goal of zero.
- Set a reminder to add one serving of a betaine-rich or folate-rich food to a meal each day, such as spinach in an omelet or a serving of lentils at dinner. Use the app to replace one alcoholic drink per week with a non-alcoholic option, and record how it feels.
- Review food logs weekly and look for patterns over at least three months. If you are pregnant, share your logged nutrition summary with your healthcare provider at prenatal visits so they can check whether any nutrient gaps need attention. Track progress toward the goal of zero alcohol consumption throughout pregnancy.
This article summarizes an observational research study and is for general education only. It is not medical advice. The study found weak associations between nutrients and child outcomes, which do not prove cause and effect. Pregnant women should avoid alcohol and talk with a doctor, midwife, or registered dietitian before making changes to their diet or taking any supplements.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.