New research study points to a surprising risk of caffeine and pregnancy: Mothers-to-be who drink caffeine, even in small amounts, could have shorter kids.

New Study Suggests Pregnant Women Drinking Coffee May Stunt Child Growth | Is Matcha Tea a Healthier Alternative?

Almost everyone drinks caffeine around the world – including pregnant women.

But is it risky to drink caffeine while pregnant? Most pregnant women are assured it's safe to have one cup of coffee daily because it won't trigger preterm deliveries or miscarriages. Still, new research points to a surprising risk: Mothers-to-be who drink caffeine, even in small amounts, could have shorter kids.

So now you might ask, “What can I replace coffee with while pregnant?” Keep reading for a full breakdown of this study and how switching from coffee to matcha may be a wise choice for an expecting mother. Learn more about how matcha may affect your pregnancy as well as you read on.

What is the safest caffeinated drink for pregnant women?

Moderate Caffeine Consumption During Pregnancy

The new study suggests that consuming caffeine lower than the recommended daily amount for pregnant women may impact childhood growth. According to the findings published in JAMA, exposure to caffeine in the womb – even just a ½ cup of coffee (36mg of caffeine) daily – may be linked to a shorter height in childhood.

To be clear – there is no reason to sound the alarm on caffeine and pregnancy. We are not talking about a massive height difference – findings point to approximately a 2-cm height difference – and researchers have stated there are limitations to the study and more research is needed.

Though it's important to note (as we did briefly earlier in this report) that the latest findings contradict current guidance standards by the American College of Obstetricians and Gynecologists (ACOG), which recommends pregnant women limit caffeine consumption to less than 200mg daily, equivalent to about two cups of coffee (6 ounces). 

To put this amount of caffeine into context across different caffeinated beverages, typically, an 8-ounce cup of coffee has around 95-200 mg of caffeine, a can of soda has 35-45 mg of caffeine, an energy drink has 70-100mg of caffeine, and a cup of green tea or matcha powder has 14-60 mg of caffeine.

Different amounts of caffeine in caffeinated beverages

How does caffeine consumption while pregnant impact a child in-utero?

The potential mechanism remains unclear, but researchers do know that caffeine is a neural stimulant that the fetus cannot metabolize. 

The fetus and placenta do not produce CYP450, the primary enzyme required for caffeine metabolism – and over the course of a woman's pregnancy, her availability to metabolize caffeine slows down. For pregnant women in their first trimester, caffeine has a very short life in the body, being quickly metabolized into paraxanthine in as little as 3 hours. By the third trimester, however, women can take up to 10 hours to metabolize caffeine. 

How caffeine metabolism slows down throughout pregnancy | consider tea over coffee

So this means that the breakdown product of caffeine – paraxanthine – accumulates in the fetal tissue across the placenta over time if a mother is regularly drinking coffee – especially into the 2nd and 3rd trimesters of her pregnancy. So as pregnancy progresses, this means that the fetus could be exposed to accumulating caffeine. 

Specifics of how the study was set up and conducted

In the study, researchers evaluated data from two prior studies – the Collaborative Perinatal Project (CCP) and the Environmental Influence on Child Health Outcomes Study (ECHO) – trying to determine whether maternal caffeine consumption is associated with stunted child growth. 

The research team looked at concentrations of caffeine and its breakdown product – paraxanthine – in blood samples they collected from over 2,400 pregnant women in the two previous studies. The team looked for an association between expecting mothers' caffeine consumption and child height.

Analysis revealed children of mothers who consumed caffeine while pregnant were shown to be shorter in height at age 4 compared with mothers who did not – and the height gap widened each year through 8 years of age.  

"To be clear, these are not huge differences in height, but there are these small differences in height among the children of people who consumed caffeine during pregnancy," explained Dr. Jessica Gleason – lead author of the study. 

It's important to consider the limitations of this study. For example, researchers did not consider paternal height, maternal diet, or nausea/vomiting. 

It's also entirely possible kids will catch up in terms of height, as researchers only found an association between caffeine consumption and child height – not a cause-and-effect link.

This is why going forward, Gleason and her research team hope to explore the association between maternal caffeine consumption and child growth later in childhood (early 20s) to see if they do catch up. 

Can I have matcha instead of coffee while pregnant? Try cutting back on coffee and switching to matcha.

Have you ever considered switching from coffee to matcha while pregnant or while trying to conceive?  

Matcha also contains caffeine, though how the body processes caffeine from matcha tea is quite different from coffee. 

The caffeine in matcha acts slower, giving you more of a gentle, constant energy boost for 6-8 hours. This is because the caffeine in matcha binds with an amino acid called L-theanine, which makes matcha tea caffeine metabolize in a slower, more controlled manner.

A cup of espresso – on the other hand – enters your bloodstream within minutes, giving you a jittery and anxious bolt of energy. 

Tea caffeine– unlike caffeine found in coffee – is non-addictive. In fact, transitioning from drinking coffee to matcha tea is one of the best ways to curb caffeine consumption without experiencing unpleasant withdrawal symptoms.

It's also the healthier option over coffee, soda, or energy drinks for your children. Thinking of sharing matcha tea with your kids? Find out are what age should your child start drinking matcha tea.

So if you want to reduce your caffeine intake but still get your energy boost, consider adding drinking matcha to your daily ritual list. Matcha also comes with a long list of women-specific health benefits.

Enjoy matcha with your child when they are older than 12. Here's why

The bottom line | Switching to matcha may help curb your caffeine intake while pregnant

Over the years, there have been a number of inconsistent studies regarding whether consuming caffeine during pregnancy is safe for the child. Currently, the recommended caffeine intake guideline for pregnant women is 200 mg/day. 

Still, more evidence in recent years points to limiting your caffeine consumption below the recommended daily limit.

Going forward, we hope the scientific community can gain clarity on exactly when in pregnancy caffeine consumption should be limited and how the body processes caffeine from tea differently than caffeine in coffee and sodas.

While caffeine is considered safe, drinking too much – whether you are pregnant or not – does raise concerns. In large doses, caffeine is associated with restlessness, trouble sleeping, heightened anxiety, as well as chronic headaches and migraines. 

Always check in with a trusted healthcare provider before making any significant lifestyle or dietary changes, as this could impact your mood or existing medical conditions.

Expecting? These articles may interest you:

Matcha Caffeine and Pregnancy

Switching from Coffee to Matcha

The Connection Between Matcha, L-theanine, and Increased Productivity

How matcha helps support hormonal balance


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Disclaimer: These statements in this blog post have not been evaluated by the Food and Drug Administration. The information provided here is for educational purposes only and should not be considered as medical advice. It's essential to consult with a qualified healthcare professional before making any dietary or lifestyle changes


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