Low vitamin D-contained HF diet significantly aggravated HF-decreased muscle gene expression involved in vitamin D responsive genes including CYP24 and CYP27, fatty acid β-oxidation such as CPT1, PPARα, UCP2, UCP3, VLCAD, and LCAD and mitochondrial biogenesis including PGC1, NRF1, and Tfam without changing mtDNA copy number. This evidence concerns the gene UCP2 and hydrops fetalis.