The Impact of the Contraceptive Pill on Gut Health By Chiza Westcarr

The combined oral contraceptive pill (to be called the pill hereafter), is one of the most prescribed medications in the world. Over 100 million women use the pill globally as their preferred form of contraception, with its highest use being in the Western world.

The pill usually contains a combination of ethinyl estradiol and one of several progestins, synthetic forms of the naturally occurring steroid hormones oestrogen and progesterone produced by the ovaries. They have been altered to mimic natural oestrogen and progesterone.

There is no doubt that the pill has been revolutionary for women. In Australia the release of the first pill in 1961 heralded a shift in women’s reproductive rights. It started out only being available to married women, giving them the freedom to plan parenthood, and enter the workforce. It was considered not only easy to use, but also extremely effective at preventing ovulation, and therefore pregnancy.

Today nearly 60 percent of women take the pill for non-contraceptive reasons, which include lighter periods and reduced period pain (dysmenorrhoea). The pill may improve acne and the symptoms associated with polycystic ovarian syndrome (PCOS), premenstrual syndrome (PMS) and endometriosis. It may also reduce the risk of certain cancers such as ovarian and uterine (womb) cancer.

Like all medications however, the pill may cause side effects, which vary from woman to woman. Some of these side effects are listed on the leaflet found in the box, while others are not.

In this article, I will look at the impact of the pill on gut health.

The gut is home to trillions of microbes, made up of bacteria predominantly, as well as fungi, viruses, yeasts and archaea. Collectively, they are referred to as the microbiota, and are found scattered along the entire length of the gastrointestinal tract. These microbes are mainly bacteria located in the large colon. Among its functions that include aiding digestion, the absorption of nutrients, and educating the immune system, 70% of which resides in the gut lining, a healthy gut microbiota also regulates hormones which includes the metabolism of oestrogen. Excess oestrogen and its metabolites are conjugated in the liver in readiness for elimination via urine and bile in faeces via the gut. Some studies demonstrate adverse effects associated with the pill on the gut and its microbiota. It has been associated with Crohn’s disease and Ulcerative Colitis, although the mechanism of action remains to be elucidated.

The pill has been linked to gut dysbiosis, or an imbalance in the microbiota. Gut dysbiosis is associated with the overgrowth of opportunistic microbes including bacteria and yeasts. Gut dysbiosis impacts hormone function. Oestrogen metabolism which occurs in the gut is disrupted when there is a loss in microbial diversity due to a reduced number of oestrogen-metabolising bacteria called the oestrobolome.

The oestrobolome regulates oestrogen by secreting an enzyme called betaglucuronidase. This prepares excess hormones including conjugated oestrogen for excretion. Diet determines how efficiently this occurs.

A World Health Organisation (WHO) report identified that women on the pill showed key nutrient depletions such as folic acid, vitamins B2, B6, B12, Vitamin C and Vitamin E, along with minerals magnesium, selenium and zinc. A highly refined processed diet, high in sugar and devoid of fibre, has very little nutritional value. This type of diet has been demonstrated to not only drive inflammation, and cause gut permeability, but also results in the production of excess betaglucuronidase which leads to oestrogen dominance. This occurs because instead of excess conjugated oestrogen being excreted in faeces, it is deconjugated by betaglucuronidase and exits the gut via the permeable gut lining, where it is then recirculated back around the body via the circulatory system. This unbound active oestrogen binds to oestrogen receptors leading to various physiological responses. Symptoms linked to leaky gut and oestrogen dominance include joint pain, headaches, depression, anxiety, bowel changes, difficulty losing or gaining weight experienced by some women. The oestrobolome is also affected by other factors such as the use of antibiotics and alcohol consumption.

To mitigate any potential adverse effects of the pill, as well as to optimise the oestrobolome and microbiota in general, a fibre rich, nutrient dense diet is key.

Fresh fruit and vegetables are fermented by the microbiota producing metabolites called short chain fatty acids (SCFAs). Apart from providing energy to enterocytes, which are the cells lining the gut, SCFAs have a systemic anti-inflammatory effect. They also indirectly assist with gut motility. Regular bowel movements ensure that excess conjugated oestrogen is eliminated and not recirculated. Increasing fibre intake will reduce the amount of betaglucuronidase production. Fruits, vegetables, legumes, nuts, and meat are all rich sources of those nutrients that may be deficient. Zinc and l-glutamine will also serve to restore the gut lining.

Find out more about Chiza’s work at

www. nutritionalskincareacademy.com

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