Zinc intake linked to lower asthma risk for overweight, obese kids

Zinc is an essential part of nearly 3,000 different proteins, and it impacts how these proteins regulate every cell in our body. The micronutrient is required for many biological processes, including growth and development, neurological function and immunity. It is naturally found in protein-rich foods such as meat and shellfish, with oysters among the highest in zinc content.

The mineral has been linked to a protective effect against asthma in children and adults, but the results are inconsistent.

The current prevalence of asthma among children in the United States is 6.5% (2021 CDC numbers), a decrease from 9.5% in 2011. However, overweight and obese children have a significantly higher risk of asthma than children with a healthy weight.

New results published in the World Allergy Organization Journal​ indicated that overweight and obese children with the highest average intakes of zinc (at least 11.96 mg per day) had a 40% lower risk of asthma than those with the lowest average intake (less than 5.7 mg per day).

“Our findings align with existing research, even if the precise mechanisms by which zinc influences asthma in overweight or obese individuals remain incompletely known,” wrote researchers from Fujian Medical University.

Study details​

The new study used data from the U.S. National Health and Nutrition Examination Survey (NHANES, 2011–2020) and analyzed 4,597 children and adolescents of which 963 had asthma.

Results—which show correlation and not causation—indicated that increasing intakes of zinc were associated with decreasing risk of asthma. Specifically, intakes between 5.7 mg and 8.4 mg per day were associated with a 13% reduction in risk, compared to the lowest intake group, while intakes between 8.4 mg and 11.95 mg per day were associated with a 32% reduction in risk.

Commenting on the potential mechanisms of action, the researchers noted that zinc may exert an effect on the release of pro-inflammatory cytokines, which are produced in high levels in asthmatics. Additionally, obesity and overweight conditions are associated with chronic low-grade inflammation. Data from in vitro​ and in vivo​ studies also suggests zinc may play a role in protecting the epithelium in lungs from damage.

“In conclusion, this multifaceted role of zinc in mitigating oxidative stress, modulating immune response, and anti-inflammatory effects highlight its potential as a therapeutic target for alleviating symptoms in overweight or obese asthmatics,” the researchers wrote.

Source: World Allergy Organization Journal​
2024, Volume 17, Issue 5, 100900, doi: 10.1016/j.waojou.2024.100900​   
“Association between dietary zinc intake and asthma in overweight or obese children and adolescents: A cross-sectional analysis of NHANES”
Authors: C. Cheng, et al.