A recent report claims that sugar intake during pregnancy is linked to children later having allergies and allergic asthma. Does that mean that sugar causes asthma and allergies in kids?
Researchers from the Queen Mary University of London looked about 9,000 mothers and their children to better understand if there was a link between maternal sugar intake during pregnancy and allergies and asthma. (Previous research claimed there was an association between consumption of high-sugar drinks and asthma in kids.) Their study was recently published in the European Respiratory Journal.
They evaluated maternal intake of free sugars during their third trimesters, and then conducted allergy and asthma tests on the children when they were seven years old. Free sugars are monosaccharides and disaccharides that are added to foods from the consumer, food preparer or manufacturer, as well as those naturally present in foods such as fruit or honey.
Though the overall link between free sugar intake and asthma was weak, the study found that there were strong links with allergy and allergic asthma—meaning the child was diagnosed with asthma and had positive skin allergy tests.
The researchers compared 20 percent of mothers who had the highest sugar intake with those who had the lowest sugar intake and found a 38% increased risk for allergy in the offspring (73% for allergy to two or more allergens) and 101% for allergic asthma. The team did not find a link between the mothers’ sugar intake and eczema or hay fever.
“Sugar intake in early childhood was not associated with increased risk of these outcomes,” noted Annabelle Bédard, PhD, one of the researchers.
Does Sugar Intake During Pregnancy Cause Allergies and Asthma in Kids?
The team believes that the link could be due to the high fructose levels in the sugar, which could cause a postnatal allergic immune response and lead to allergic inflammation in the childrens’ developing lungs.
Though Seif Shaheen, PhD, the lead researcher, said the study doesn’t point to high sugar intake as a cause of allergy and asthma, the team did note a link that should be further investigated. That needs to be done in a different sampling of mothers and children. This study was observational; a randomized controlled trial would be required to say sugar causes the allergies and asthma in kids.
What Women Need to Know
So should you be super-careful about sugar intake during pregnancy? Yes, but not because it causes allergies and asthma— this isn’t confirmed yet. But there are plenty of other perks to watching your sugar consumption while expecting.
“Though we don’t know for sure what this study means to allergy and asthma risk, we do know that a high sugar diet is linked to cardiometabolic risks,” said Sharon Palmer, a California-based registered dietitian nutritionist and author of Plant-Powered for Life. Eating too much sugar can mean that women aren’t eating other healthy foods; it also gives them excess energy, which can lead to detrimental weight gain.
Emerging evidence suggests that the gut microbiota influences the immune response and potential allergic responses. The gut microbiota need to feed on high-fiber plant foods, Palmer noted.
Sheena Cruickshank, PhD, a professor of biology medicine and health at the University of Manchester, agreed that research indicates the microbiome is altered in those with allergies—and that can be affected by their delivery, type of milk fed and diet as the child grows.
“Future studies should look to take these variables into account so we can understand the full relationship between maternal diet during pregnancy and allergic disease in the offspring,” she said.
Palmer broke down what sugars women should pay attention to.
“We shouldn’t worry about naturally occurring sugars in the diet—we should be limiting added sugars to no more than 10% of calories—this is a recommendation for everyone, including pregnant women,” she said.
Palmer said she thinks it’s too early to know for sure that sugar is the culprit of allergies in the developing child.
“However, other dietary factors have been seen to carry over to the fetus, so it may be that we find that the impact of high-sugar diets may carry over, too. We just don’t know enough about this right now,” she added.