INSULIN RESISTANCE + GLYCEMIC CONTROL IMPACT
Ironically, many women are put on hormonal contraceptives for the management of undesirable symptoms associated with PCOS when in actuality, hormonal contraceptives may only mask symptoms but further worsen the root cause of PCOS: insulin resistance. There are a few ways hormonal contraceptives impact insulin resistance: 1. the previously mentioned impact on thyroid function 2. the role and regulation of insulin production and 3. mineral depletion, more specifically related to magnesium depletion [5,7,9]. Estrogen (and remember, this is not real estrogen but a synthetic form so it’s not acting as your real estrogen would) has receptors on the pancreas, the organ in the body where insulin is produced, having the ability to alter the cells which produce insulin [9]. When glucose is present, estrogen enhances insulin secretion more prominently than normal which further interferes with carbohydrate metabolism and blood sugar regulation [9]. Repeated exposure to exaggerated, high levels of insulin on the cells can lead to worsening of insulin resistance (in those genetically predisposed) and irregular control of glucose metabolism. Furthermore, the mechanism of how is not clearly understood, but the research repeatedly shows women on hormonal contraceptives have decreased levels of magnesium [5,9]. The imperative role of magnesium in the body can be further explained here, but in summation, magnesium is required for energy production and is responsible for binding insulin to the cell to allow for glucose absorption. Additionally, low magnesium leads to high calcium in relation to magnesium ratio which increases the risk of clotting disorders and thrombosis (or a blood clot) [5].
MICRONUTRIENT DEPLETION + OXIDATIVE STRESS IMPACT
Magnesium is not the only micronutrient depleted by birth control. Hormonal contraceptives have been shown to deplete folate, vitamin B2, vitamin B6, vitamin B12, vitamin C, selenium and zinc [5]. The mechanisms by which this can occur are not clearly understood but again, the research is solid in proving non-hormonal contraceptive users versus those using are significantly depleted in these nutrients. Vitamin C and zinc are two important micronutrients which function as antioxidants to reduce oxidative stress (more on oxidative stress here and its impact on women’s health). Hormonal contraceptives increase the rate that vitamin C is used up and alters how the tissues can absorb and utilize it [5]. Similar mechanisms impair the absorption of zinc and selenium. Oxidative stress on the body already increases from the effects of hormonal contraceptives but with the depletion of nutrients to combat this stress, the exposure to free radicals only increases leading to further risks of cancer and cardiovascular disease [5]. Selenium, another powerful antioxidant, is also required for thyroid function. In every thyroid cell, selenium is a required cofactor that activates the thyroid gland. Without selenium, in combination with all of the aforementioned impacts of birth control on thyroid functioning, the risks of thyroid complications rise substantially both while taking birth control and long after discontinuation [5,10].
References
Taylor CM, Pritschet L, Jacobs EG. The scientific body of knowledge – whose body does it serve? A spotlight on oral contraceptives and women’s health factors in neuroimaging. Frontiers in Neuroendocrinology. 2021;60:100874. doi:10.1016/j.yfrne.2020.100874
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3. Brighten J. Beyond the Pill. HarperOne; 2020.
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7. Torre F, Calogero AE, Condorelli RA, Cannarella R, Aversa A, La Vignera S. Effects of oral contraceptives on thyroid function and vice versa. Journal of Endocrinological Investigation. 2020;43(9):1181-1188. doi:10.1007/s40618-020-01230-8
8. Medau HJ, Rauskolb R. Das Verhalten des thyroxinbindenden Globulins (TBG) unter oraler hormonaler Kontrazeption [Serum level of thyroxin-binding globulin under oral contraception (author's transl)]. Klin Wochenschr. 1975 Aug 1;53(15):727-9. German. doi: 10.1007/BF01468705. PMID: 1219185.
9. Cortés ME, Alfaro AA. The effects of hormonal contraceptives on glycemic regulation. The Linacre Quarterly. 2014;81(3):209-218. doi:10.1179/2050854914y.0000000023
10. Ventura M, Melo M, Carrilho F. Selenium and thyroid disease: From pathophysiology to treatment. International Journal of Endocrinology. 2017;2017:1-9. doi:10.1155/2017/1297658
11. Mihajlovic J, Leutner M, Hausmann B, et al. Combined hormonal contraceptives are associated with minor changes in composition and diversity in gut microbiota of Healthy Women. Environmental Microbiology. 2021;23(6):3037-3047. doi:10.1111/1462-2920.15517
12. Khalili H. Risk of inflammatory bowel disease with oral contraceptives and menopausal hormone therapy: Current evidence and future directions. Drug Safety. 2015;39(3):193-197. doi:10.1007/s40264-015-0372-y
13. Pletzer B, Harris TA, Hidalgo-Lopez E. Previous contraceptive treatment relates to grey matter volumes in the hippocampus and basal ganglia. Scientific Reports. 2019;9(1). doi:10.1038/s41598-019-47446-4
