Vegetarian Diet While Pregnant Will Not Turn Your Kid Into a Drug Addict in Later Life

Researchers have shown that vegetarian women are more likely to have kids with substance abuse problems, but diet alone can't be blamed. Lisa Lake/Getty Images for Anheuser-Busch

Devout vegetarians might return to their meat-eating ways following research that animal-free diets could cause their kids to become alcoholics, but good news: you don't have to trade in that tofu yet. Bad news: at least one researcher believes the new data shouldn't be dismissed.

The study, published in Alcoholism: Clinical and Experimental Research, found that adolescents who drank or smoked weed or cigarettes also had mothers who ate less meat during their pregnancy. The explanation for the connection, the researchers theorize, could be that vitamin B12, which is high in meat, dairy and egg products, impacts fetal brain development.

Related: Vitamin B3, Birth Defects and Miscarriages: Pregnant Women Shouldn't Start Taking Supplement Because of One Study

The study included more than 5,000 teens living in the United Kingdom, and showed that kids whose mothers were vegetarians were 28-percent likelier to have alcohol-related behavioral problems. They also had a 48-percent higher chance of occasionally smoking weed and a 21-percent increase in weekly tobacco use.

But the study findings should be taken with a grain of vegetarian salt, says the National Health Service. After the findings were reported in the Daily Mail, the National Health Service issued a statement calling the story "scaremongering." The governmental agency explained that the results should not shame expectant mothers into eating meat. As they note,"It is already recommended that vegetarian and vegan mums-to-be take special care to ensure they get enough of certain nutrients that are found in meat and fish, such as vitamin B12, vitamin D and iron."

Pregnant women do have increased nutritional needs to support their babies, especially in iron, vitamin B12 and calcium as the NIH advises, but it is entirely possible to get the recommended amounts on a plant-based diet.

The study definitely does not show a causal relationship between diet and teen substance abuse. Rather, as the NHS statement emphasizes, this was a "cohort" study, an analysis that looks at several factors simultaneously in order to spot patterns. Cohort studies can find only associations, they cannot ever determine whether one factor caused another. So there is no proof here that pregnant women who are vegetarians are more likely to give birth to children who will eventually abuse substances.

Other weaknesses pervade the work. Pregnant women were not tested for vitamin B12, so evidence to back up the deficiency theory is completely lacking. The teenagers were self-reporting their substance use, and their declarations may have been inaccurate. And other issues could also have played a role; as much as researchers try to eliminate factors like income or social life, doing so completely is impossible.

Yet at least one researcher says the findings cannot be easily dismissed. Nicole Prause, a California-based neuroscientist mainly focused on sex but who also studies addiction, believes the study has some merit. "I wouldn't immediately write it off," she says. "There does seem to be something there."

Follow-up research is needed to look more closely at the association. In the meantime, what can worried expectant mothers take away from this?

"Don't change your diet if you're pregnant," says Prause.