Given its location and ubiquitous distribution, sialic acid can mediate or modulate a wide variety of physiological and pathological processes; however, there is scarce data regarding the associations between sialic acid serum levels and sex, age and menopause. The present study evaluated the age-related changes in serum sialic acid (SA) levels in 97 elderly subjects, including men and postmenopausal women. A significant increase in serum levels of sialic acid in postmenopausal women and a significant decrease in men were observed in an age-dependent manner. Furthermore, in postmenopausal women, positive correlations were observed between the total serum sialic acid level and age in all decades and subgroups. The total serum concentration of sialic acid in the postmenopausal women group exhibited a particular pattern; significantly lower levels were observed in subjects in the intermediate postmenopausal period compared with those in the first decade of post menopause and then higher levels again as the women get older (late climax), thus the concentration increased according to the age of the individual.Copyright © 2020, Spandidos Publications.