Childhood allergies may be linked to pregnant mum’s sweet tooth

Research exists correlating high intake of sugary drinks in children and increased incidence of asthma.¹

Now, in an interesting new study, a possible connection has been made between a mother’s high added sugar intake while pregnant and the incidence of allergy and allergic asthma in offspring.

An added sugar and allergy connection

The Avon Longitudinal Study of Parents and Children is a large cohort study in the U.K., and since the early 1990s researchers have recruited and tracked the health of nearly 9,000 mother-children pairs.²

Using this data, researchers from Queen Mary University of London (QMUL) analysed mum’s added sugar intake while pregnant via a food frequency questionnaire, taken in the third trimester, along with respiratory and allergic outcomes in their children at 7 years of age through skin testing for common allergens including dust mite, cat and grass.

Added, or free, sugars are defined by the World Health Organisation as “all monosaccharides and disaccharides added to foods by the manufacturer, cook, or consumer, plus sugars naturally present in honey, syrups, and fruit juices”.³ They are not to be confused with naturally occurring sugars found in whole food like fruit, vegetable or dairy.

After controlling for potential confounding factors, a strong association was found between maternal added sugar intake and incidence of allergies or allergic asthma, independent of the child’s early life sugar exposure.

Comparing the 20% of women with the highest added sugar intake (between 82g and 345g a day) with the 20% who consumed the least (less than 34g a day), a 38% increased risk for allergy and 101% for allergic asthma was found.

Research is in early days

The research team “speculate that the associations may be explained by a high maternal intake of fructose causing a persistent postnatal allergic immune response leading to allergic inflammation in the developing lung.”⁴

However, it is too early to assume a direct cause and effect relationship. Though this association, along with known high sugar consumption in Western culture, should spur further investigation.

There are other factors that are thought to influence the incidence of allergy in offspring to consider, including the health of the intestinal microbiome of both mother and child. Considering 70% of the immune system lies in the gastrointestinal tract, it isn’t surprising there is influence over immune function.

So, what’s next?

“The first step is to see whether we can replicate these findings in a different cohort of mothers and children,” says lead researcher Professor Seif Shaheen.

“If we can, then we will design a trial to test whether we can prevent childhood allergy and allergic asthma by reducing the consumption of sugar by mothers during pregnancy. In the meantime, we would recommend that pregnant women follow current guidelines and avoid excessive sugar consumption.”

Children under the age of 2 should not consume added sugars at all, and everyone else should work toward limiting intake of added sugars to 6 teaspoons/25g a day.

Here are our top tips for reducing added sugar intake.

A good thing to remember is diets high in added sugar are often high in processed and packaged foods.

Focusing on consuming mostly real, whole foods will naturally lower added sugar intake, as well as provide beneficial nutrients that assist the body in operating optimally.

For pregnant mum’s, this will also benefit the health of the unborn child. What mums eat while pregnant may also begin to shape flavor preferences of her child later in life, so get that good, real whole food in as early as you can.

By Angela Johnson (BHSc Nut. Med.)

References:

1. Berentzen, NE, van Stokkom, VL, Gehring, U, Koppelman, GH, Schaap, LA, Smit, HA, & Wijga, AH 2015, ‘Associations of sugar-containing beverages with asthma prevalence in 11-year-old children: the PIAMA birth cohort’, European Journal Of Clinical Nutrition, vol. 69, no. 3, pp. 303-308.
2. Bédard, A Northstone, K Henderson, AJ & Shaheen, SO 2017, “Maternal intake of sugar during pregnancy and childhood respiratory and atopic outcomes”, European Respiratory Journal, vol. 50, no. 1.
3. World Health Organization 2014, The science behind the sweetness in our diets, viewed 11 July 2017, <http://www.who.int/bulletin/volumes/92/11/14-031114/en/>
4. University of Bristol 2017, Sugar intake during pregnancy is associated with allergy and allergic asthma in children, Press release, viewed 11 july 2017, available at: http://www.bris.ac.uk/news/2017/july/sugar-pregnancy.html