Zinc Supplements Fall Short for Boys With Duchenne Muscular Dystrophy

A clinical trial investigating oral zinc supplementation in boys with Duchenne muscular dystrophy (DMD) found the treatment did not significantly improve key health measures.¹

Published in Nutrients, the study focused on zinc’s role in muscle health and cellular function and aimed to assess changes in bioelectrical impedance parameters, which are indicators of muscle integrity, body composition, and hydration. Despite its potential, zinc supplementation showed limited benefits, raising concerns about the adequacy of current nutritional recommendations for patients with DMD.

The researchers found that nearly 30% of the 33 boys in the study, aged 5 to 24, had zinc levels below the healthy range at the start, indicating a risk of zinc deficiency. After 4 months of supplementation, while zinc supplementation slightly reduced the percentage of boys with low zinc levels to 20%, the change was not statistically significant. There were also no statistically significant changes in muscle function or hydration measures such as phase angle (PA) and bioelectrical impedance vector analysis (BIVA), which monitor cellular health and body composition.

“DMD is a progressive neurodegenerative disease that induces permanent changes in muscle cell membranes,” the study authors said, pointing to the unique challenges of treating children with DMD. “Therefore, zinc supplementation may not be enough to alter or improve the measured parameters.”

Muscle damage caused by DMD may limit zinc’s effectiveness. | Image credit: Celt Studio – stock.adobe.com

Zinc plays a crucial role in maintaining cell membranes and supporting muscle function. However, researchers found that the muscle damage caused by DMD may limit zinc’s effectiveness. PA and BIVA results showed a decline in muscle health with age, and the study confirmed that these measures were not improved by zinc supplementation. The absence of changes in these parameters suggests that DMD’s progressive muscle deterioration requires more targeted interventions.

Zinc is an essential trace mineral required in small amounts but vital for nearly 100 enzymes that support critical bodily functions, including cell growth, DNA creation, tissue repair, and immune function.² It plays a key role during periods of rapid growth, such as childhood, adolescence, and pregnancy when adequate zinc intake is essential for healthy development. The current recommended daily amount of zinc in adults is generally 11 mg a day for men and 8 mg for women, with an upper limit of 40 mg per day.³ The recommended dose ranges from 3 to 8 mg for children depending on age, and 9 to 11 mg for teens.

“Given inflammation and lean mass loss in DMD, doses higher than those recommended for zinc are likely necessary to achieve an effect on the measured parameters,” the study authors said.¹

Beyond the limited effectiveness of zinc supplements, the study also pointed to the usefulness of bioelectrical impedance measures like PA and BIVA in monitoring the health of patients with DMD. These tools can help track changes in body composition and detect worsening muscle loss, offering insights into disease progression and potential interventions.

The authors noted that future studies should include a more representative sample with a longer study period to determine the generalizability of these findings.

“Considering the functions of zinc and the pathophysiology of DMD, it is essential to implement strategies to prevent or treat zinc deficiency in this population,” the authors added. “Further studies investigating larger and safer doses of oral zinc supplementation are warranted.”

References

1. Vermeulen-Serpa KM, Lopes MMGD, Alves CX, et al. Effect of oral zinc supplementation on phase angle and bioelectrical impedance vector analysis in Duchenne muscular dystrophy: a non-randomized clinical trial. Nutrients. 2024;16(19):3299. doi:10.3390/nu16193299
2. Zinc. The Nutrition Source. Updated March 2023. Accessed October 25, 2024. https://nutritionsource.hsph.harvard.edu/zinc/
3. Zinc. HHS. October 4, 2022. Accessed October 25, 2024. https://ods.od.nih.gov/factsheets/Zinc-Consumer/