Functionality of Supplements and Anti-aging: Functionality of Supplements—Fertility

In recent years, due to societal factors such as the advancement of women in society, the trend of women marrying later, and the aging of the desired child-rearing age, age-related infertility has been increasing [1]. In fact, the Centers for Disease Control and Prevention (CDC) in the United States reported that the average age of first childbirth was 21.4 years in 1970, but it was 25.1 years in 2008 [2]. Furthermore, the same agency points out that the number of women giving birth to their first child after the age of 35 has increased from 1 in 100 in 1970 to 1 in 12 in 2006, indicating the aging of women at the time of childbirth [3, 4]. On the other hand, the number of infertility patients due to the aging of women’s desire to have children is rapidly increasing in our country, and the number of babies born in 2018 due to assisted reproductive technology (ART) treatments such as in vitro fertilization and embryo transfer is 56,979, with 1 in 16 being an in vitro fertilization baby [5]. Infertility can indeed be called a national disease related to aging, and the use of supplements as part of integrated medicine is frequently performed in addition to ART. However, among the pregnancy activity (hereinafter, fertility) supplements, there are those on the market that lack evidence, such as “improving the quality of eggs,” “improving sperm motility,” and “increasing implantation power.” One of the reasons for this is the reality that supplements whose safety and effectiveness have not been proven are circulating without public regulation by the Food and Drug Administration (FDA) and others [6]. On the other hand, evidence of nutritional interventions centered on supplements for fertility is accumulating due to recent literature and statistical methods and cohort studies. In this section, we will introduce and overview the latest evidence, focusing on folic acid and vitamin D, which are particularly becoming established as evidence for contributing to fertility.