Will antibiotics used during caesarean section make the child obese?

Is childhood obesity definitely caused by eating too much junk food and not exercising? There are several other possibilities. A study by Columbia University in the United States showed that children born by caesarean section and their mothers taking antibiotics during pregnancy may cause children to become obese.

A study by the University of Southern California said that air pollution and secondhand smoke are also factors in childhood obesity. Another study in Israel said that artificial sweeteners can make you fat. Even scholars say this is something they have never thought of. How did it happen?

Caesarean section and antibiotics make children fat

The somewhat surprising Columbia University study looked at data from pregnant women who didn't smoke between 1998 and 2006 and followed their children until age seven; 16 percent of the 436 cases had antibiotics used by the mothers in the second or third trimester.

The study found that children of these mothers were 84% more likely to be obese at age seven than those of other mothers. The research team said this is the first study to look in depth at the impact of antibiotics during this period.

They believe that antibiotics can affect the microorganisms in the body and also affect the fetus through the placenta. The bacteria that naturally grow in the intestines can help maintain the health of the body. When antibiotics affect the intestinal flora, the imbalance may cause some diseases, such as obesity.

Noel Mueller, a postdoctoral researcher at the Columbia School of Public Health, said that the results of this study are not to stop people from using antibiotics, but to understand that antibiotics have an impact in the early stages of growth, and it is also a new warning about the problem of antibiotic abuse.

The study also found that, without considering the effects of the aforementioned antibiotics, children born by elective or non-elective caesarean section have a 46% higher risk of obesity. Andrew Rundle, assistant professor at the institute, said they did not find any difference between elective and non-elective caesarean sections.

This is different from previous studies. Through experiments, it can be confirmed that caesarean section is also a factor that causes childhood obesity. The reason is similar to the use of antibiotics: caesarean section does not go through the vagina, which reduces the baby's chance of being exposed to some healthy bacteria.

Air pollution and secondhand smoke make children fat

In addition to cesarean sections and antibiotics, air pollution and secondhand smoke can also make children fat. A study by the University of Southern California tracked the data of 3,318 children with an average age of ten in 12 communities in Southern California until they were 18 years old, including exposure to smoking environments and community air quality, transportation data, etc. The variables they controlled included gender, initial BMI index, asthma, amount of exercise, parents' education and income, the ratio of rich to poor in the community, and the distance of parks and open spaces from home.

The results showed that compared with children who were not exposed to secondhand smoke and lived a little further away from the main road, the BMI of children exposed to air pollution was 0.8 higher on average, those exposed to secondhand smoke were 0.85 higher, and those exposed to both were 2.15 higher. Rob McConnel, professor of preventive medicine at USC, said that the study broke the long-held belief that "obesity is caused by too many calories and too little exercise." In fact, that is only part of the reason, but the reasons why air pollution and secondhand smoke cause obesity need to be further understood.

Sugar Substitutes Make You Fat

For obese or diabetic patients, sugar substitutes are often an indispensable dessert. However, studies now point out that sugar substitutes can also make you fat. This does not mean that sugar substitutes are deceptive, but that sugar substitutes affect intestinal bacteria and thus affect the body's metabolism.

The research team of the Weizmann Institute of Science in Israel added three sugar substitutes, namely saccharin, sucralose and aspartame, to the diet of mice and compared them with the control group. After eleven weeks, they found that the mice showed symptoms of glucose intolerance, that is, the body's cells' response to glucose decreased, and too much glucose caused blood sugar to rise, which is a sign of metabolic disorders turning into diabetes.

The research team then fed these glucose-intolerant mice antibiotics to eliminate intestinal bacteria, and found that the symptoms of glucose intolerance disappeared. They then transferred the feces of other glucose-intolerant mice into these sterilized mice, and found that they became glucose intolerant again, indicating that intestinal bacteria are the key factor.

They also recruited seven healthy subjects and asked them to eat the maximum acceptable amount of sugar substitutes for a week. After a week, four of them showed glucose intolerance, and their intestinal bacterial species distribution also changed, which was related to the bacterial species distribution of patients with previously known metabolic diseases. The research team believes that this phenomenon seems to have personalized characteristics, and some people will be affected by sugar substitutes, while others will not.

This finding has disturbed many people: the food industry thought it had found a safe and effective substitute, but now it has found that the opposite is true; government agencies in charge of food additives did not think there would be any problems with sugar substitutes in the past, but now they must face this problem. Stephen Pagani, a spokesman for the European Food Safety Authority (EFSA), said that the authority will decide at an appropriate time whether to submit the latest research results to an expert meeting for discussion.

Scholars have different views on this. Some say that this study has the potential to develop new metabolic disease treatments, while others emphasize that the causal relationship is not yet clear. Yolanda Sanz, a nutritionist and member of the EFSA expert meeting, believes that the study is too small and it is too early to draw a conclusion.