Norgestrel / ethinyl estradiol can affect this through 2 different nutrient pathways: Vitamin C, Zinc. This medication is commonly used for Contraception.
Each nutrient below contributes to this impact through a different mechanism.
Even a modest shortfall in vitamin C can leave the immune system less resilient, showing up as more frequent colds, flus, or lingering infections that are slow to clear. Vitamin C concentrates to very high levels inside neutrophils, where it helps fuel their oxidative burst, regulate antioxidant enzymes, and support normal cell survival, so low vitamin C can mean these “first‑responder” white blood cells do not work at full strength. Clinical trials are mixed but intriguing: in a substantial subset of studies, vitamin C supplementation improved neutrophil functions such as oxidative burst, antioxidant enzyme activity, and even reduced premature neutrophil cell death in very sick patients, suggesting that correcting low vitamin C may help the body respond more effectively when infections strike.
Van Straten M, Josling P. Preventing the common cold with a vitamin C supplement: a double-blind, placebo-controlled survey. Adv Ther. 2002 May-Jun;19(3):151-9. Carr AC, Maggini S. Vitamin C and Immune Function. Nutrients. 2017 Nov 3;9(11):1211. Moore A, Khanna D. The Role of Vitamin C in Human Immunity and Its Treatment Potential Against COVID-19: A Review Article. Cureus. 2023 Jan 13;15(1):e33740. Bhoot HR, Zamwar UM, Chakole S, Anjankar A. Dietary Sources, Bioavailability, and Functions of Ascorbic Acid (Vitamin C) and Its Role in the Common Cold, Tissue Healing, and Iron Metabolism. Cureus. 2023 Nov 23;15(11):e49308. Liugan M, Carr AC. Vitamin C and Neutrophil Function: Findings from Randomized Controlled Trials. Nutrients. 2019 Sep 4;11(9):2102.
Zinc deficiency impairs immune defenses by reducing T‑cell activity and weakening resistance to infection. Low zinc levels increase susceptibility to recurrent infections, especially respiratory illnesses such as the common cold, bronchitis, and pneumonia. Clinical studies show that zinc supplementation can strengthen immune response and lower mortality when used alongside standard treatment for severe pneumonia. In a placebo‑controlled trial in elderly participants, zinc supplementation decreased the incidence of infections by 66% and improved cell‑mediated immunity.
Shah UH, Abu-Shaheen AK, Malik MA, Alam S, Riaz M, Al-Tannir MA. The efficacy of zinc supplementation in young children with acute lower respiratory infections: a randomized double-blind controlled trial. Clin Nutr. 2013 Apr;32(2):193-9. Prasad AS. Zinc: role in immunity, oxidative stress and chronic inflammation. Curr Opin Clin Nutr Metab Care. 2009 Nov;12(6):646-52. Wang L, Song Y. Efficacy of zinc given as an adjunct to the treatment of severe pneumonia: A meta-analysis of randomized, double-blind and placebo-controlled trials. Clin Respir J. 2018 Mar;12(3):857-864. Marianna K. Baum, Shenghan Lai, Sabrina Sales, J. Bryan Page, Adriana Campa, Randomized, Controlled Clinical Trial of Zinc Supplementation to Prevent Immunological Failure in HIV-Infected Adults, Clinical Infectious Diseases, Volume 50, Issue 12, 15 June 2010, Pages 1653–1660.
Some side effects may be linked to nutrient depletion caused by this medication.
Studies suggest that women using oral contraceptives might have lower levels of vitamin C within their white blood cells (leukocytes) and platelets. This depletion could be linked to reduced activity of antioxidant enzymes like glutathione peroxidase (GPx) and glutathione reductase (GR) in the blood. These enzymes play a role in protecting cells from damage. Research also shows that supplementing with vitamin C, alongside vitamin E, can significantly increase the activity of these antioxidant enzymes in women taking OCs. This suggests that vitamin C supplementation might be beneficial for women on birth control pills.
Research suggests that oral contraceptives (OCs) may play a role in vitamin B6 deficiency. A deficiency is concerning because vitamin B6 plays a crucial role in mood regulation and blood sugar control. Some women using OCs experience symptoms like depression and impaired glucose tolerance, which could potentially be linked to this vitamin B6 deficiency. Low vitamin B6 levels are independently associated with an increased risk of blood clots in both arteries and veins (venous and arterial thromboembolism, or TE). This association suggests that the B6 deficiency caused by OCs might partly explain the higher risk of TE observed in women using birth control pills. This highlights the importance of ensuring adequate vitamin B6 intake for women on OCs and therefore supplementation should be considered.
Research suggests a potential decrease in magnesium levels in women using Oral Contraceptives (OCs). Studies have shown that women taking OCs have significantly lower serum magnesium compared to those not using them. Interestingly, the type of pill or duration of use doesn't seem to influence the degree of magnesium depletion. The observed decrease in magnesium with OC use might be associated with an increased risk of blood clots. Supplementation with magnesium should be considered during oral contraceptives use.
Studies suggest that oral contraceptives (OCs) may contribute to zinc deficiency. Research has shown a significant decrease in serum zinc levels, the zinc circulating in the blood, in women taking OCs. This decrease is thought to be due to potential changes in how the body absorbs, excretes, or utilizes zinc within tissues. Due to its vital role in many bodily functions, ensuring sufficient zinc intake through supplementation should be considered for women on birth control pills.
Oral contraceptives (OCs) have been linked to a decrease in Vitamin B12 levels. Studies have shown a significant reduction in serum B12, the vitamin circulating in the blood, in women taking OCs for extended periods. One US study found a 40% decrease in B12 levels after five years of OC use. This decrease is concerning because vitamin B12 plays a crucial role in converting a form of folate (N-methyltetrahydrofolic acid) into its active form (tetrahydrofolic acid). This active folate is essential for healthy red blood cell production and other bodily functions. Due to the vital role of vitamin B12, supplementation when using OCs long-term should be considered.
Women using oral contraceptives (OCs) for extended periods may experience a decrease in their folate levels. Studies suggest that OC use might lower blood folate levels by up to 40%. This depletion can be a concern because folate plays a crucial role in red blood cell production. One research finding highlights a case where a patient developed anemia and nerve problems (polyneuropathy) after stopping vitamin B12 therapy, suggesting that folate deficiency might have been the main underlying issue. Supplementation of folate should be considered during oral contraceptive use.
Studies suggest a potential for mild thiamine (vitamin B1) deficiency with long-term use of Oral Contraceptives (OCs). One finding showed that red blood cell activity of an enzyme dependent on thiamine (transketolase) decreased during OC treatment. This decrease indicates that the cells might not have enough thiamine to function optimally, suggesting a mild thiamine deficiency induced by the contraceptives. Supplementation with thiamine (vitamin B1) should be considered for women using OCs.