Vitamin D Deficiency Linked to Early Puberty in Girls
Adequate levels of vitamin D have been linked to a variety of health benefits like better cognition, immunity and heart health. Now a new study reveals that vitamin D supplementation may also help delay early onset of puberty in girls.
Puberty generally begins between the ages of 10 and 14 for girls and between 12 and 16 years of age for boys. However, precocious puberty is diagnosed in girls when sexual development begins before the age of 8 and changes occur before the age of 9. Past studies have found that unusually early puberty can negatively affect social behavior, psychological development and can reduce adult height potential and may shift some lifelong health risks.
Vitamin D deficiency has been linked to a number of diseases like cancer, obesity and autoimmune disease. Recent studies have also found low vitamin D levels in girls with precocious puberty.
However, scientists still do not know the exact relationship between vitamin D deficiency and early sexual development. To understand this relationship, researchers compared blood levels of the vitamin between girls with early and normal development.
The study involved 110 girls between the ages of seven to 10 years. Researchers said 75 girls exhibited normal patterns of development and 35 girls were classified as having precocious puberty.
Researchers found that girls with precocious puberty were twice more likely than girls with age-appropriate development to have a severe vitamin D deficiency. The study found that 44 percent of girls in the precocious puberty group had severe vitamin D deficiency compared to only 21 percent of the group with age-appropriate physical development.
For the study, researchers also looked at the activity of neurons responsible for stimulating the release of a hormone that triggers the ovulation process. Using the neuron-stimulating compound called N-methyl-D-aspartate, or NMDA, to activate the neurons responsible for releasing gondadotropin-releasing hormone, or GnRH, researchers found that vitamin D was associated with a suppression of the NMDA-mediated neuronal activities on GnRH neurons.
"If we understand more about the action mechanism of vitamin D on GnRH neuronal activities, we can find a clue to control of precocious puberty using vitamin D or related molecules," study lead author Min Sun Kim, MD, PhD, assistant professor at Chonbuk National University Medical School in Jeonju, South Korea, said in a news release.
"Our results suggest that vitamin D may inhibit early pubertal onset and/or the rapid progression of puberty, at least in part, through the suppression of NMDA-mediated GnRH neuronal excitation in humans," she explained.
The findings were presented Monday at The Endocrine Society's 95th Annual Meeting in San Francisco.