The term birth control can mean something different to everyone. While birth control is how you prevent pregnancy, it is also a way to let people take their reproductive health and future into their own hands. It is not always about avoiding pregnancy – people use birth control to help regulate hormones, family plan, and, in certain cases, protect themselves against sexually transmitted diseases.

According to the CDC, 65% of U.S. women aged 15-49 were using some form of birth control as of 2019,1 a number that goes up to 70% if the female is an athlete.2 Over a lifetime, 99% of women will have used one type of birth control or another.3

Birth control comes in many forms, including implants, IUDs, shots, vaginal rings, patches, pills, condoms, cervical caps, sponges, spermicide and gel, tubal ligation, and vasectomy. People may combine a few forms depending on the reason for using it. The pill, which is one option that provides hormones, remains one of the most common options, as almost 13% of women3 and 29% of female athletes2 use it as their primary method of contraception.

From altered hormone levels to changes in metabolism, hormonal contraceptives can influence how your body absorbs and processes nutrients. To keep your body functioning at its best, it’s important to be mindful of these changes and adjust your diet accordingly. In this blog post, we’ll explore the key nutritional considerations for people using hormonal birth control and offer tips for supporting your body through diet and supplements.

How birth control affects your body’s nutritional needs

Hormonal contraceptives, such as the birth control pill, have been around since the 1960s. They work by altering the levels of estrogen and progesterone in your body. These hormones prevent ovulation, thicken cervical mucus, and create changes in the uterine lining to prevent pregnancy. However, even the low-dose formulation can affect your body’s metabolism and change the user's nutritional needs.

There are several ways that birth control affects nutrition needs:

1. Reduced levels of B vitamins 

Hormonal birth control, particularly birth control pills, can decrease the levels of important B vitamins, including folate (B9), B6, and B12. Some of the earliest research on oral contraceptives showed users had a lower average blood level of folate compared to a control group. Over time with use, levels continued to decline. When the group stopped taking birth control, folate levels returned to normal within three months. The researchers suggested birth control users had poor folate absorption, higher excretion in urine, and accelerated metabolism of it while on the pill.4 

Folate is essential for cell division, the production of red blood cells, proper methylation, and amino acid metabolism. Focus on folate-rich foods such as leafy greens, beans, lentils, avocado, and fortified cereals.

Population-based research in the United States found that blood levels of vitamin B6, essential for the function of the nervous and immune systems, were significantly reduced in women taking oral contraceptives who did not take dietary supplements.5 

More recent research suggests that dietary intake and supplements can help negate decreased B vitamin blood levels with long-term contraceptive use.6 Some of Thorne’s best supplements for women on birth control looking to manage B vitamins include:

  • Thorne’s B-Complex #12: A B-vitamin blend formulated with extra B12 and folate (both in their active, tissue-ready forms), this health solution supports energy production and healthy neurological function.*
  • Thorne’s B-Complex #6: A B-vitamin blend with extra B6 (including active, tissue-ready pyridoxal-5’ phosphate), this formula supports hormone balance and is also NSF for Sport Certified®.*

2. Lowered magnesium and zinc

As shown above, birth control can interfere with vitamin and mineral absorption, excretion, or tissue turnover rates, reflecting lower blood levels. Magnesium and zinc are two minerals of concern. 

Magnesium is an essential element in as many as 600 enzymatic reactions, including energy production, muscle relaxation, cardiovascular health, blood sugar metabolism, brain function, bone health, and more. Zinc is involved in the metabolism of RNA and DNA, signal transduction, gene expression, and numerous functions in the brain including learning processes. 

Research from almost 60 years ago was the first to observe that women on oral contraceptives had lower zinc blood levels compared to women not on the pill.7 Several studies since then have confirmed this observation and some have demonstrated slight decreases in selenium levels, too.8 Selenium is most notably involved in antioxidant pathways and the functioning of the thyroid.

Research has repeatedly shown that serum magnesium levels along with several trace elements are impacted by the use of oral contraceptives.9,10 

In addition to loading up on nuts, lentils, and green vegetables for magnesium, or meat, shellfish, and nuts for zinc, Thorne has a few different supplement options for those at risk for low magnesium or zinc levels:

3. Potential impact on vitamin D 

Since vitamin D plays a crucial role in bone health, immune function, and mood regulation, it’s important to ensure you’re getting enough, especially since vitamin D deficiency is an extremely common problem worldwide. 

Research suggests that hormonal birth control can positively impact vitamin D metabolism, although not enough to ignore this fundamental vitamin. One study examining the effects of oral estrogens combined with progestins found that women on hormonal oral contraceptives had, on average, vitamin D levels that were about 8 ng/mL higher than those not on oral contraceptives. 11  

On the other hand, studies of women with PCOS taking oral contraceptives – which is a common therapy for this condition – show that oral contraceptives may lower vitamin D levels.12  

Most of us don’t get the vitamin D we need from foods, like egg yolks, oily fish, beef liver, mushrooms, or fortified foods, nor receive much from the sun thanks to protective clothing and sunblock. 

Test your levels with Thorne’s Vitamin D Test and look to maintain normal vitamin D levels, available in various amounts to fit your specific needs – in capsule or liquid forms. Thorne’s Vitamin D-5,000 is NSF Certified for Sport.

4. Increased need for antioxidants 

Hormonal contraceptives can increase oxidative stress and rates of vitamin metabolism in the body, which may contribute to inflammation and accelerate the aging process. To counteract this, focus on antioxidant-rich foods in the diet, like fruits, vegetables, nuts, and seeds.

Research has seen lower levels of ascorbate acid (vitamin C) in the white blood cells of women who use oral contraceptives with estrogen.13 In other research, lower levels of antioxidant activity and higher oxidative stress were noted in women taking oral contraceptives.14  

Researchers stated that supplementary vitamin C and vitamin E can help maintain normal antioxidant activity in those who take oral birth control.* Some Thorne health solutions to consider include:

5. Increased fluid retention 

Reproductive hormones are known to play a role in the renin-angiotensin-aldosterone system, which is the system that regulates how much your body holds onto and releases water, regulating blood pressure, (water) weight, blood volume, and electrolyte balance.

The best way to help maintain normal blood pressure, blood volume, and electrolyte balance is to maintain daily hydration and exercise. Movement will help the body maintain regulation of the renin-angiotensin-aldosterone system, minimize swelling, and keep the kidneys healthy. And if you exercise heavily be sure to support any electrolyte loss.

Although hydration needs should be personalized, women generally need at least 73 ounces of water (or about 9 cups) a day. If exercising, consider 17-20 ounces before and 1.5 times the amount lost during exercise afterward. Consider electrolytes if exercising for 60 minutes or more, in hot or humid conditions, or at high intensity. 

Support your electrolyte balance with Thorne’s Catalyte, an electrolyte restoration powder. This formula is NSF Certified for Sport and promotes performance, endurance, and recovery, making it a great option for athletes.*

Additional tips for optimizing nutrition on birth control

  • Eat a balanced diet: The foundation of any healthy diet is variety. Aim for a well-rounded diet that includes a mix of whole grains, lean proteins, healthy fats, and plenty of fruits and vegetables to support overall health.
  • Watch your gut health: Birth control can sometimes affect the gut flora, leading to digestive issues like bloating or constipation. Eating a diet high in fiber, prebiotics, and probiotics (found in foods like yogurt, kefir, sauerkraut, and kombucha) can support a healthy digestive system.
  • Monitor your weight and metabolism: Some people experience changes in weight or metabolism while using hormonal birth control. A balanced diet and regular physical activity are key to managing weight and maintaining overall health.

The takeaway

Hormonal birth control is a safe and effective option for preventing pregnancy, but it can have an impact on your body’s nutritional needs. By being proactive about your diet and ensuring you're getting the right balance of vitamins and minerals, you can help your body stay healthy and supported during birth control use.

Always consult with a healthcare professional before making significant dietary changes or starting supplements, especially if you have concerns about nutrient deficiencies or interactions with your birth control. With the right approach to nutrition, you can ensure that your body remains balanced and nourished, no matter which contraceptive method you choose.

Testing and tracking your hormones and blood levels of B vitamins, magnesium, zinc, and vitamin D while on birth control is easier than ever with these test options that come with Thorne’s personalized plans:

References

  1. Daniels K, Abma JC. Current Contraceptive Status Among Women Aged 15–49: United States, 2015–2017. https://www.cdc.gov/nchs/data/databriefs/db327-h.pdf [Accessed 12.30.24]
  2. Ryall S, Ohrling H, Stellingwerff T, et al. Contraception choice for female endurance athletes: what’s sport got to do with it? a cross-sectional survey. Sports Med. 2024 Dec;54(12):3181-3197.
  3. Daniels K, Mosher WD, Jones J. Contraceptive Methods Women Have Ever Used: United States, 1982–2010. https://www.cdc.gov/nchs/data/nhsr/nhsr062.pdf [Accessed 12.30.24
  4. Shojania AM, Hornady G, Barnes PH. Oral contraceptives and serum-folate level. Lancet. 1968;1(7556):1376-1377.
  5. Morris MS, Picciano MF, Jacques PF, Selhub J. Plasma pyridoxal 5’-phosphate in the US population: the National Health and Nutrition Examination Survey, 2003-2004. Am J Clin Nutr. 2008;87(5):1446-1454.
  6. Wilson SM, Bivins BN, Russell KA, Bailey LB. Oral contraceptive use: Impact on folate, vitamin B6, and vitamin B12 status. Nutr Rev. 2011;69(10):572-583. 
  7. Halsted JA, Hackley BM, Smith JC Jr. Plasma-zinc and copper in pregnancy and after oral contraceptives. Lancet. 1968;2(7562):278-279.
  8. Fallah S, Sani FV, Firoozrai M. Effect of contraceptive pill on the selenium and zinc status of healthy subjects. Contraception. 2009;80(1):40-43.
  9. Akinloye O, Adebayo TO, Oguntibeju OO, et al. Effects of contraceptives on serum trace elements, calcium and phosphorus levels. West Indian Med J. 2011;60(3):308-315.
  10. Palm Er YM, Sara Ceno A, Vva Iar Elli A, Ca Rlomagn OG. Oral contraceptives and changes in nutritional requirements. Eur Rev Med Pharmacol Sci. 2013;17(13):1804-1813.
  11. Ciebiera M, Włodarczyk M, Słabuszewska-Jóźwiak A, et al. Vitamin D serum levels in women using contraception containing drospirenone – a preliminary study. Arch Med Sci. 2019;15(2):554-557.
  12. Namli Kalem M, Hizli D, Kamalak Z, et al. Effect of combined oral contraceptive use on serum 25-hydroxy vitamin D levels and ultrasound parameters in patients with polycystic ovary syndrome. Gynecol Endocrinol. 2016;32(4):281-284.
  13. Veninga KS. Effects of oral contraceptives on vitamins B6, B12, C, and folacin. J Nurse Midwifery. 1984;29(6):386-390.
  14. Zal F, Mostafavi-Pour Z, Amini F, Heidari A. Effect of vitamin E and C supplements on lipid peroxidation and GSH-dependent antioxidant enzyme status in the blood of women consuming oral contraceptives. Contraception. 2012;86(1):62-66.