5 Essential Nutrients Commonly Depleted by the Pill
Oral contraceptives are among the most commonly used and highly effective drugs in the developed world. Research has highlighted however that the widespread use of oral contraceptives may be significantly affecting bodily levels of many essential vitamins and minerals.1-5
Read on to find out more about 5 essential nutrients commonly depleted by the pill (what’s worrying is there are many more):
• Folic acid
• Vitamin B12
• Vitamin E
Oestrogen therapy, including the use of oral contraceptives, lowers serum magnesium levels and can cause deficiency of this vital mineral.6,7 And this is of particular concern for the majority of people who already have low dietary magnesium intake coupled with 21st century lifestyle factors that can quickly use up magnesium stores. These include poor sleep, high intensity exercise, chronic stress and high intake of caffeine, sugar and processed foods.7-12
Magnesium has become a hot topic in recent years, with research linking this versatile mineral to energy, sleep, mood, hormone balance, muscle relaxation and much more. Given the body’s widespread needs for magnesium, the typically low dietary intakes and the constant drain on the body’s stores, it is particularly concerning that one of the most commonly prescribed medications in the developed world may be depleting levels even further.
And what’s even more alarming is that when magnesium depletion occurs, it alters the calcium: magnesium ratio which can affect blood coagulation.13 It is likely then that magnesium deficiency may contribute to the thromboembolic complications associated with oestrogens.6,7 On the basis of current research, it seems reasonable to recommend therefore that women taking oral contraceptives should supplement their diets with additional magnesium.
The zinc status of women using oral contraceptives has been of concern since 1968, when it was observed that they had lower plasma zinc levels than those not using this form of contraception.14,15 And several studies done during the following decades have confirmed this finding.16-20
Zinc is an essential trace element, used as a cofactor for more than 300 different enzymes, and as such it is used in every cell, organ, bone, tissue, and fluid in our bodies. Zinc is involved in immune and skin health, reproduction, energy, eyesight and much more. According to the World Health Organisation (WHO), the global prevalence of zinc deficiency is around 31%.
The changes that happen as a result of increased oestrogen via oral contraceptive use may reduce the amount of zinc carried in the blood and also increase the amount of zinc used by bodily tissues.21,22 When these changes occur, dietary zinc needs would be greater in women using oral contraceptives.20
Whilst not all studies report decreased zinc levels, the majority indicate that oral contraceptives - even low dose versions - do negatively affect the nutritional status of this mineral.16,20,23-31 In addition, a recent systematic review found a decrease in zinc, selenium, phosphorus and magnesium in women taking oral contraceptives.32 These reductions were also linked to the duration of contraceptive use. Supplementation with zinc, may therefore be a useful support for women taking oral contraceptives. Zinc is best supplemented with copper as these two minerals are antagonists which mean they compete for binding sites in the body. Excess zinc can lead to a copper deficiency and vice versa.
Shortly after the introduction of oral contraceptives, studies appeared to suggest their consumption might reduce blood folate levels.33-37 The hormonal content of oral contraceptives was however much higher in the 1960s and 1970s when these initial studies were carried out, which has raised the question of how relevant these results still are today? A more recent systematic review and meta-analysis answered this question and concluded, “Because of the reduction in blood folate concentrations associated with the use of oral contraceptives, it is critical for women of childbearing age to continue folate supplementation during oral contraceptive use”.38
Folic acid is particularly important during the first 4 weeks of pregnancy for the prevention of neural tube defects (NTDs). In recognition of the importance of folic acid for women during reproductive years and the potential folate-depleting effects of oral contraceptives, an oral contraceptive fortified with folate was made available in 2012 in some markets to help reduce the risk of NTDs in a pregnancy conceived during use or shortly after the discontinuation of oral contraceptive products.39,40
There is also some evidence that oral contraceptives can increase the rate of progression of cervical dysplasia to cervical cancer, and that folic acid can slow or reverse this dysplasia.41,42
Current research supports the recommendation that all women of child bearing age taking oral contraceptives should also take daily folic acid supplements. Folic acid is best supplemented in the body-ready form of 5-methyltetrahydrofolate (5-MTHF). This is because some people are genetically less able to convert folic acid into this active form, making supplementation less effective. Providing the body-ready, active 5-MTHF form of folic acid bypasses the need for conversion and provides reassurance that your folate stores are being topped up.
Several studies have found low levels of vitamin B12 in women using oral contraceptives, compared to non-users.20,43-52 There is a close relationship between folate and vitamin B12 metabolism in the body, however it is still not well understood how oral contraceptives may cause low vitamin B12. As with low folate levels, low maternal B12 status is also considered to be an independent risk factor for neural tube defects (NTDs).53
In addition to its protective role in pregnancy, vitamin B12 is involved in over 100 daily functions; it helps the blood to carry oxygen and is essential for healthy nerves, DNA synthesis and to help eliminate toxins. It is found in rich supply in animal products and is the only vitamin that can’t be reliably supplied by a varied wholefood plant-based diet and regular exposure to the sun.
A recent systematic review found that oral contraceptives deplete vitamin B1254 and supports the view that vitamin supplements may be helpful in women taking oral contraceptives.55
Vitamin E is well known for its diverse effects on health – as an antioxidant, for skin health, immune function and to protect your heart too.
Research has shown that oral contraceptives increase markers of oxidative stress and decrease blood levels of vitamin E. Additional research found a significant increase in the clotting activity of blood platelets in women taking oral contraceptives, and this is naturally associated with a decrease in blood levels of vitamin E.56-58 The researchers found that vitamin E supplementation increased blood levels of vitamin E and decreased the clotting activity of platelets. They concluded that the negative effects of oral contraceptives on clotting may be dependent on low vitamin E which can be corrected with vitamin E supplements.59
Many people are unaware that vitamin E isn’t just a single nutrient but rather appears in nature as a collection of different forms (alpha, beta, gamma and delta tocopherol). Vitamin E is therefore best supplemented in the form of mixed tocopherols to best reflect this natural balance and optimally support your body’s needs.
Daily supplementation may help to support improved levels of key nutrients
Research has shown that oral contraceptives can deplete blood levels of many essential vitamins & minerals and here we have highlighted just a few; there are many, many more. It seems reasonable to recommend therefore, on the back of this collective evidence, that women taking oral contraceptives may benefit from supplementing their diets with a daily multivitamin & mineral to help to counter these possible negative effects. Selecting a high quality daily multivitamin & mineral supplement that provides nutrients in body ready, active forms therefore seems a worthwhile investment in both immediate and long term health.
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2. Berg G, Kohlmeier L, Brenner H. Effect of Oral Contraceptive Progestins on Serum Copper Concentration. Eur J Clin Nutr. 1998; 52:711-5.
3. Ghayour-Mobarhan M, Taylor A, New SA, Lamb DJ, Ferns GA. Determinants of Serum Copper, Zinc and Selenium in Healthy Subjects. Ann Clin Biochem. 2005; 42:364-75.
4. Tamura T, Picciano MF. Folate and Human Reproduction. Am J Clin Nutr 2006;83: 993-1016.
5. Prevention of Neural Tube Defects: Results of the Medical Research Council Vitamin Study. Mrc Vitamin Study Research Group. Lancet. 1991; 338:131-7.
6. Seelig MS. Increased need for magnesium with the use of combined oestrogen and calcium for osteoporosis treatment. Magnes Res 1990; 3:197-215
7. Seelig MS. Interrelationship of magnesium and estrogen in cardiovascular and bone disorders, eclampsia, migraine, and premenstrual syndrome. J Am Coll Nutr 1993; 12:442-58
8. Stanton MF, Lowenstein FW. Serum magnesium in women during pregnancy, while taking contraceptives, and after menopause. J Am Coll Nutr 1987; 6:313-9
9. Akinloye O, Adebayo T, Oguntibeju O, Oparinde D, Ogunyemi E. Effects of contraceptives on serum trace elements, calcium and phosphorus levels.West Indian Med J 2011; 60: 308-315.
10. Hameed A, Majeed T, Rauf S, Ashraf M, Jalil M, Nasrullah M, Hussan A, Noreen R. Effect of oral and injectable contraceptives on serum calcium, magnesium and phosphorus in women. J Ayub Med Coll Abbottabad 2001; 13: 24-25.
11. Olatunbosun D, Adeniyi F, Adadevoh BK. Effect of oral contraceptives on Serum magnesium levels. Int J Fertil 1974; 19: 224-226.
12. Blum M, Kitai E, Ariel Y, Schnierer M, Bograd H. Oral contraceptive lowers serum magnesium. Harefuah 1991; 121: 363-364.
13. Cowan JA. Introduction to the biological chemistry of magnesium. ed. J.A. Cowan. New York. VCH;1995.
14. Halsted JA, Hackley BM, Smith JC, Jr. Plasma-zinc and copper in pregnancy and after oral contraceptives. Lancet 1968; 2: 278-279
15. King JC. Do women using oral contraceptive agents require extra zinc? J Nutr 1987; 117: 217- 219
16. Prasad AS, Oberleas D, Moghissi KS, Stryker JC, Lei KY. Effect of Oral Contraceptive Agents on Nutrients: Ii. Vitamins. Am J Clin Nutr. 1975; 28:385-91.
17. Akinloye O, Adebayo T, Oguntibeju O, Oparinde D, Ogunyemi E. Effects of contraceptives on serum trace elements, calcium and phosphorus levels.West Indian Med J 2011; 60: 308-315.18. Briggs Mh, Briggs M, Austin J. Effects of steroid pharmaceuticals on plasma zinc. Nature 1971; 232: 480-481
19. Prema K, Ramalakshmi Ba, Babu S. Serum copper and zinc in hormonal contraceptive users. Fertil Steril 1980; 33: 267-271.
20. Fallah S, Sani Fv, Firoozrai M. Effect of contraceptive pill on the selenium and zinc status of healthy subjects. Contraception 2009; 80: 40-43.
21. King JC. Do women using oral contraceptive agents require extra zinc? J Nutr 1987; 117: 217- 219
22. Chilvers DC, Jones MM, Selby PL, et al. Effects of oral ethinyl oestradiol and norethisterone on plasma copper and zinc complexes in post-menopausal women. Hormone Metab Res 1985; 17:532-5.
23. Tyrer LB. Nutrition and the pill. J Reprod Med 1984; 29:547-50.
24. Webb JL. Nutritional effects of oral contraceptive use: a review. J Reprod Med 1980; 25: 150-156.
25. Prema K, Ramalakshmi Ba, Babu S. Serum copper and zinc in hormonal contraceptive users. Fertil Steril 1980; 33: 267-271.
26. Smith JC, Brown ED. Effects of oral contraceptive agents on trace element metabolism - a review. In: Prasad AS (ed). Trace Elements in Human Health and Disease. Vol.II, Essential and Toxic Elements. New York: Academic Press, 1976. 315-45.
27. Vir SC, Love AH. Zinc and copper nutriture of women taking oral contraceptive agents. Am J Clin Nutr 1981; 34:1479-83
28. Hinks LJ, Clayton BE, Lloyd RS. Zinc and copper concentrations in leukocytes and erythrocytes in healthy adults and the effect of oral contraceptives. J Clin Pathol 1983; 36:1016-21.
29. Powell-Beard L, Lei KY, Shenker L. Effect of long-term oral contraceptive therapy before pregnancy on maternal and fetal zinc and copper status. Obstet Gynecol 1987; 69:26-32.
30. Liukko P, Erkkola R, Pakarinen P, et al. Trace elements during 2 years' oral contraception with low-estrogen preparations. Gynecol Obstet Invest 1988; 25:113-7.
31. Thane, C W et al : Oral contraceptives and nutritional status in adolescent British girls. Nutrition Research, 2002, 22, 449-462
32. Dante G et al. Vitamin and mineral needs during the oral contraceptive therapy: a systematic review. Int J Reprod Contracept Obstet Gynecol. 2014 Mar;3(1):1-10
33. Trowbridge M, Jr., Wadsworth R, Moffitt E. Malabsorption associated with gluten enteropathy, do oral contraceptives interfere with folate metabolism? J Maine Med Assoc 1968; 59: 240-242.
34. Paton A. Oral contraceptives and folate deficiency. Lancet 1969; 1: 418.
35. Ryser J, Farquet J, Petite J. Megaloblastic anemia due to folic acid deficiency in a young woman on oral contraceptives. Acta Haematol 1971; 45: 319-324.
36. Whitehead N, Reyner F, Lindenbaum J. Megaloblastic changes in the cervical epithelium. Association with oral contraceptive therapy and reversal with folic acid. JAMA 1973; 226: 1421-1424
37. Shojania AM. Oral contraceptives: effect of folate and vitamin B12 metabolism. Can Med Assoc J 1982; 126: 244-247
38. Shere, Mahvash, et al. "Association between use of oral contraceptives and folate status: a systematic review and meta-analysis." Journal of Obstetrics and Gynaecology Canada 37: 430-438.
39. Castano PM, Aydemir A, Sampson-Landers C, Lynen R. The folate status of reproductive-aged women in a randomised trial of a folate-fortified oral contraceptive: dietary and blood assessments. Public health nutrition. 2014 Jun;17(6):1375-83.
40. Fruzzetti, F. Beyaz P An oral contraceptive fortified with folate Women's Health1 (Jan 2012): 13-9.
41. Butterworth CE, Hatch KD, Gore H, et al. Improvement in cervical dysplasia associated with folic acid therapy in users of oral contraceptives. Am J Clin Nutr 1982; 35:73-82.
42. Check WA. Folate for oral contraceptive users may reduce cervical cancer risk. J Am Med Assoc 1980; 244:633-4.
43. Wilson SM, Bivins BN, Russell KA, Bailey LB. Oral Contraceptive Use: Impact on Folate, Vitamin B(6), and Vitamin B(1)(2) Status. Nutr Rev. 2011; 69:572-83.
44. Mooij PN, Thomas CM, Doesburg WH, Eskes TK. Multivitamin supplementation in oral contraceptive users. Contraception 1991; 44:277-88.
45. Lussana F, Zighetti Ml, Bucciarelli P, Cugno M, Cattane M. Blood levels of homocysteine, folate, vitamin B6 and B12 in women using oral contraceptives compared to non-users. Thromb Res 2003; 112: 37-41.
46. Shojania AM. Oral contraceptives: effect of folate and vitamin B12 metabolism. Can Med Assoc J 1982; 126: 244-247
47. Wertalik L, Metz E, Lobuglio A, Balcerzak S. Decreased Serum B 12 Levels With Oral Contraceptive Jama 1972; 221: 1371-1374.
48. Sutterlin M, Bussen S, Rieger L, Dietl J, Steck T. Serum Folate And Vitamin B12 Levels In Women Using Modern Oral Contraceptives (Oc) Containing 20 Microg Ethinyl Estradiol. Eur J Obstet Gynecol Reprod Biol 2003; 107: 57-61.
49. Riedel B, Bjorke Monsen A, Ueland P, Schneede J. Effects Of Oral Contraceptives And Hormone Replacement Therapy On Markers Of Cobalamin Status. Clin Chem 2005; 51: 778-781.
50. Shojania Am, Wylie B. The Effect Of Oral Contraceptives On Vitamin B12 Metabolism. Am J Obstet Gynecol 1979; 135: 129-134.
51. Veninga K S. Effects Of Oral Contraceptives On Vitamins B6, B12, C, And Folacin. J Nurse Midwifery 1984; 29: 386-390.
52. Hielt K, Brynskov J, Hippe E, et al. Oral contraceptives and the cobalamin (vitamin B12) metabolism. Acta Obstet Gynecol Scand 1985; 64:59-63.
53. Adams MJ Jr, Khoury MJ, Scanlon KS, Stevenson RE, Knight GJ, Haddow JE et al. Elevated Midtrimester Serum Methylmalonic Acid Levels as a Risk Factor for Neural Tube Defects. Teratology. 1995; 51:311-7.
54. Dante G et al. Vitamin and mineral needs during the oral contraceptive therapy: a systematic review. Int J Reprod Contracept Obstet Gynecol. 2014 Mar;3(1):1-10
55. Basnayake S, de Silva SV, Miller PC, Rogers S. A Trial of Daily Vitamin Supplementation as a Means of Reducing Oral Contraceptive Side Effects and Discontinuation in Sri Lanka. Contraception. 1983; 27:465-72
56. Aftergood L, Alfin-Slater R B. Oral contraceptivealpha- tocopherol interrelationships. Lipids 1974; 9: 91-96.
57. Akinsanya M, Adeniyi T, Ajayi G, Oyedele M. Effects of vitamin E and folic acid on some antioxidant enzymes activities of female Wistar rats administered combined oral contraceptives. African J Biochem Res 2010; 4: 238-242.
58. Brigg M. Letter: vitamin E status and oral contraceptives. Am J Clin Nutr 1975; 28: 436.
59. Renaud S, Ciavatti M, Perrot L, Berthezene F, Dargent D, Condamin P. Influence of vitamin E administration on platelet functions in hormonal contraceptive users. Contraception 1987; 36: 347-358.
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