PTH and vitamin D deficiency: We found that allocation to the 25-hydroxy vitamin D deficiency group was not correlated with allocation to the low 1,25-dihydroxy vitamin D group, a finding that is consistent with previous reports, thereby suggesting that the potential influences of individual dietary calcium consumption, PTH levels, or individual 1-α hydroxylase capacity may play a role in determining an individual’s 25-hydroxy and 1,25-dihydroxy vitamin D levels [1,32].