Are Childhood Antibiotics Making America Fat?
A new study indicates a link may exist between antibiotic use in children and health problems later in life—including obesity.
Doctors who prescribe antibiotics to children indiscriminately aren’t doing their patients any favors.
There are many good reasons to avoid doling out these medications carelessly to patients of all ages. However, a new paper in the journal Cell Host & Microbe offers insight into why pediatric patients may be particularly vulnerable to ill effects from overuse of antibiotics—such use may increase their risk of several diseases later in life, including obesity.
From the first moments of an infant’s life, its gut is already being populated by bacteria from the mother’s body. These bacteria will go on the play an important role in regulating the long-term health of the infant, not just in the newborn period, but potentially for years to come. As the paper describes in detail, this process can be significantly affected by numerous factors, including whether the baby was born vaginally or by Cesarean section, or whether it is breastfed or given formula. Even the mother’s weight can affect the diversity of bacteria that populate the child’s gastrointestinal tract.
At various points in the child’s development, different healthful bacteria proliferate. These bacteria are necessary for proper regulation of the immature immune system in the gut, and to keep potentially harmful bacteria from overgrowing. When antibiotics are used during these early stages of growth, they can disrupt these processes, leading to a state called dysbiosis.
The study’s authors looked at both dysbiosis itself, and at the potential diseases that can result from this state. While this paper primarily sets out a framework for areas of future study, it does suggest many ways in which antibiotic use in children can lead to various lifelong health problems.
For example, by changing the population of a child’s gut, antibiotics may predispose him or her to obesity. Citing studies in mice, the authors note those given low doses of antibiotics had large differences in the kinds of bacteria in their bodies, and were more prone to being obese. Studying their droppings, those on antibiotics produced feces with fewer calories in them, indicating that the altered bacterial population caused more calories to be absorbed during digestion. (The next time you hear about research that looks stupid on its face, remember that “mouse poop calorie counts” seems pretty idiotic until the implications for people are pointed out.) While further study is needed, there is some evidence that antibiotics can have a similar effect on human infants.
In addition to obesity, antibiotic-induced dysbiosis may also play a role in the development of allergic, autoimmune and infectious diseases. The mechanisms by which this can occur are complex, and involve many different parts of the intestines, immune system, and bacterial population. Among those mechanisms are alteration in how immature immune systems recognize harmful vs. beneficial bacteria, changes in the permeability of the intestinal wall, and overgrowth of bacteria that can cause disease when unchecked by other species.
While large-scale human studies are still needed, the findings in this new paper add to the already well-established harms of overusing antibiotics. The World Health Organization warns that an era in which these potentially life-saving medications no longer work because of widespread resistance is all too imminent if steps are not taken to curb improper use. On an individual level, every medication has the potential for adverse effects, and antibiotics are no different. Patients can have allergic reactions, develop side effects like diarrhea, and increase their risk of infection with other potentially life-threatening bacteria.
As a pediatrician, I don’t think a day goes by when I don’t prescribe antibiotics several times to various patients. They play an indispensable role in the treatment of countless ailments. I’d be at a loss to cure pneumonia, urinary tract infections, or cellulitis without them. Obviously there are times when antibiotic use is absolutely warranted to treat a condition that will not resolve with it.
However, even under the clearest of clinical circumstances, their use is not without risks. Entertaining a “What’s the harm?” attitude grossly underestimates the serious downsides of careless prescribing, and medical providers who do not put the thought and time necessary into determining if they are truly indicated are doing their patients and the population at large a disservice. As this new study reminds us, there are ramifications for antibiotic use beyond the mistaken hope they will make someone’s cold go away a little faster.