By Julianne Bierwirth, RD
Coffee has a chemical complexity that, through the roasting process, creates a broad range of vibrant flavor characteristics. This same molecular diversity is also responsible for a variety of health effects in humans. Caffeine is certainly the most well-studied, but it is far from the only pharmacologically active molecule extracted during a brew. Some of these chemicals are elusive, and their effects poorly understood. Others, after decades of research, have concrete benefits and detriments firmly borne out by data.
In this 8-part blog series, we delve into the myriad truths, half-truths, and indeed, fallacies, related to the impact that coffee has on your health. Is it good for you? Is it bad for you? Is it going to make your teeth brown? Does coffee make you smarter? Read on to find out.
PART 3: COFFEE IN PREGNANCY AND CHILDHOOD
Kids are not strangers to caffeine - a 12 ounce serving of soda has around 30 mg of it. But soda consumption has fallen over the last decade, slowly being replaced with healthier alternatives. For many that means flavored water or juice. For others, including many kids and teens, that also means coffee. If children drinking coffee rings strange to you, you’re not alone. But is there any reason to think coffee is worse than soda for a child’s health? What about the effect of caffeine and coffee during even earlier stages of development?
“Research that compares coffee consumption with behaviors and health outcomes in children and expectant mothers is not definitive."
Scientific disclaimer: a major challenge in understanding the effects of coffee and caffeine in infants and children is that randomized controlled trials, the gold standard of academic research, are hard to come by. In such trials, subjects are randomly assigned to a group; exposure to coffee or no exposure at all. The problem, as you might have guessed, is that a researcher cannot randomly assign your 8-year-old to consume caffeine every day. They can study an 8-year-old who consumes caffeine of their own accord, however.
Research surrounding vulnerable populations (children, pregnant women, prisoners, and the mentally ill) is strictly regulated because each group consists of individuals unable to knowledgeably consent to research, or else subject to coercion. Thus, research that compares coffee consumption with behaviors and health outcomes in children and expectant mothers is not definitive. Nondefinitive food and nutrition research of this kind is everywhere and is one of many reasons eating healthy feels so confusing.
Starting with conception, concerns surrounding coffee abound. Women trying to get pregnant or experiencing infertility will sometimes reduce or eliminate caffeine from their diet, likely having heard that the odds of conceiving are higher without it. There have been some data to suggest an association between a substantial coffee habit (equivalent to three or more cups a day) and infertility. Yet there is other research suggesting no negative effect of caffeine at any level.
This sort of contradictory research can feel confusing and can lead to a lot of people choosing to avoid coffee just to be safe. An overview of all related research suggests that, if there is a link between coffee and infertility, moderation is the key - experts agree that a cup or two a day should be just fine. The old “all things in moderation” adage also holds true also for research surrounding complications like spontaneous abortion, premature delivery, congenital defects, and small for gestational age.
“Dozens of studies on many thousands of women have found no statistically significant effect of moderate coffee consumption (less than 200 mg caffeine/2 small cups a day) on expecting mothers or their babies.”
In most studies, adverse effects were experienced only by those drinking the most caffeine, whose use or abuse of it may have been confounded with other less healthy behaviors. For example, high-dose coffee consumption is sometimes used to cope with stress or depression, both of which present risks to conception and pregnancy. One study found that women who drank 300 mg or more caffeine per day during pregnancy were also far more likely to smoke and drink as well.
Even after birth, many new moms worry that coffee will pass through into their breast milk. During breastfeeding a very small dose of caffeine does transmit from the mother to the child. The American Academy of Pediatrics deems this small enough to be safe and not of concern except, again, in the case of women drinking many cups of coffee a day.
Some pregnant and breastfeeding women will still choose to abstain, however, it's worth noting that those who do drink coffee aren’t necessarily negligent or ill-informed. Dozens of studies on many thousands of women have found no statistically significant effect of moderate coffee consumption (less than 200 mg caffeine/2 small cups a day) on expecting mothers or their babies.
This is actually a conservative estimate - no study reviewed here found a detriment to drinking 300 mg or less per day. So put that judgy side-eye away the next time your pregnant or breastfeeding friend orders a cappuccino.
Children & Teens
The conclusions surrounding childhood coffee consumption are far less clear. Some risks are nonexistent or overblown, where others might be genuine. Much of the research surrounds energy drinks, soda, or caffeine as a whole. That means much of the data also inadvertently grapples with the effect of added sugar and doesn’t have the benefit of antioxidants seen in coffee.
The idea that coffee stunts growth in children is probably one of the most common and enduring of coffee myths. The belief is that coffee causes osteoporosis, but this is an old idea based on an outdated study and unsupported by current scientific research. Caffeine consumption does increase the elimination of calcium from the body. Theoretically the decrease in calcium could result in osteoporosis, however, this is not proven and it is also not the same as stunted growth.
Other studies have shown that caffeine, even at low doses, exhibits a cardiovascular effect on children. A single cup of coffee can result in increased blood pressure and reduced heart rate. This is probably not concerning in the short term, but the effects of a persistent caffeine habit on children’s cardiovascular health are unknown.
“Health Canada recommends a 45 mg caffeine limit for kids 4-6, a 62.5mg limit for kids 7 to 9, and an 85 mg limit for kids 10-12. For adolescents, the limit is 2.5mg caffeine for every kilogram body weight.”
Probably of greatest concern is the mental effect of caffeine on children. Disrupted sleep, obvious as it is, is a genuine struggle for parents trying to maintain healthy patterns for themselves and their children. Caffeine, as a stimulant, has the potential to disturb sleep for children even at levels found in half a cup of coffee.
In childhood and adolescence high caffeine consumption is associated with some troubling mental and behavioral issues. For example, one study found that children who exhibit symptoms of depression drink about 4 more servings of caffeine a day than their non-depressed counterparts. Is the coffee causing depression? Or is the coffee an attempt at self-medication? Without randomized controlled trials, we can’t know for sure.
Very early consumption of caffeine is also linked with other substance abuse in later years. That could be because these children get accustomed to using substances for an artificial boost. Again, however, that may be because a 13-year-old with little supervision might buy energy drinks from the corner store and also smoke with her friends outside.
Coffee may actually aid children’s health in the same way that it seems to for adults - primarily diabetes prevention. There’s no clear reason to think that at eighteen years old the benefits of coffee would magically kick in, but once again the studies that look so promising for adults cannot be done on children.
Caffeine has a dose to weight response like any other drug. A smaller child needs a proportionally smaller serving of coffee as compared to an adult. Health Canada recommends a 45 mg caffeine limit for kids 4-6, a 62.5mg limit for kids 7 to 9, and an 85 mg limit for kids 10-12. For adolescents, the limit is 2.5 mg caffeine for every kilogram body weight.
While coffee has many potential health benefits for adults, the effect during pregnancy and childhood is less clear. The research that does exist suggests that low to moderate consumption of caffeine is probably okay. Women who are lactating, pregnant, or trying to conceive should limit caffeine to less than three cups of coffee per day. Children should probably not get more than a half cup of coffee before adolescence. Finally, extreme coffee consumption during teen years may be a warning sign of mental health or behavioral concerns.
In the end, there’s always decaf. And some roasters *wink wink* know how to do that really well.
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