ICMR-NIN Study Finds Vitamin D3 More Effective for Muscle and Heart Health

Researchers at the ICMR-National Institute of Nutrition (ICMR-NIN) in Hyderabad have found that Vitamin D3 is more effective than Vitamin D2 in maintaining and restoring skeletal muscle and heart function during and after vitamin D deficiency in an animal study.

The study, titled “Dietary Vitamin D2 Is Less Potent Than Vitamin D3 at Maintaining or Restoring Structure and Metabolism of Skeletal Muscle and Heart in Male Rats,” was published in the journal Molecular Nutrition & Food Research. It evaluated the comparative effects of Vitamin D2, Vitamin D3, and a combination of both on skeletal muscle structure, metabolism, muscle strength, and cardiac function.

While vitamin D is widely recognized for regulating calcium and supporting bone health, it also plays a significant role in skeletal muscle and heart function. According to the researchers, prior evidence comparing the specific effects of D2 and D3 on these systems has been limited.

To conduct the study, scientists used weanling male Sprague-Dawley rats, placing them on diets containing Vitamin D2, Vitamin D3, a combination of both, or no vitamin D. They assessed body composition, muscle strength, muscle fibre structure, and metabolic markers alongside indicators of cardiac function.

Rats that received Vitamin D3 showed greater improvements in muscle mass, muscle fibre size, and grip strength. Vitamin D3 also demonstrated superior performance in boosting markers tied to muscle development and energy metabolism.

Similar outcomes were observed regarding heart health. Vitamin D3 produced stronger improvements in markers of cardiac contractility and metabolism, especially during recovery following periods of vitamin D deficiency.

Dr Ayesha Ismail, scientist F at ICMR-NIN and the corresponding author of the study, noted that while both forms improved calcium-related parameters, D2 proved less effective across multiple measures related to muscle and heart structure and energy metabolism.

ICMR-NIN director Dr Bharati Kulkarni stated that the findings highlight the potential advantages of Vitamin D3 in supporting skeletal and cardiac functions, while noting that further research is required.