Wine, beer, spirits—alcohol is an incredibly common substance indulged in by many people, from the occasional “celebratory” drinker to those who enjoy a drink with dinner or at the end of the day. There are binge-drinking partiers and those who abuse alcohol. We also each have our own unique alcohol tolerance which comes down to our genetics and liver function. Alcohol is technically a toxin, but one that in reasonable amounts can be metabolized and detoxified by the human liver. But that doesn’t mean that alcohol can pass through our body without other effects, including those on our hormone systems. So, how does alcohol affect our hormones and fertility, and how much do you have to drink for this to happen?
Alcohol and Hormones
Both acute and chronic alcohol drinking can interfere with hormone functioning.1 Our hormone control centers are located in two glands situated just under the brain and they are the hypothalamus and the pituitary gland. Hormone signals from these glands are put into circulation where they have effects in different areas of the body such as the ovaries. Signals sent to the ovaries in premenopausal women prompt the production of estrogen, which then sends a feedback signal to these special hormone glands—a well-regulated system! However, animal and human studies suggest that chronic alcohol intake significantly increases estrogen levels in both males and females, while also decreasing testosterone in males.1 One study reported that having five or more glasses of wine per week led to 22% higher estradiol levels compared to non-drinkers.2
How Does Alcohol Increase Estrogen?
First, alcohol consumption can increase activity of the enzyme aromatase which converts testosterone into estrogen, meaning greater levels of estrogen. The one exception may be red wine, as described by one group of researchers who suggest that another compound in grapes and red wine (not alcohol) may oppose alcohol’s effect on aromatase.3 In this study, participants drank one 8-oz glass of wine (either red or white) daily for 21 days. Those who drank red wine had significantly higher testosterone levels, compared to those who were given white wine.
Secondly, estrogens have to be metabolized by the liver and they do so in a multistep process (similar to alcohol and other toxins). In Phase I, estrogens get broken down into either 2-hydroxyestrogen (2-OHE), 4-OHE or 16-OHE. The 2-OHE form is the most protective and least likely to cause cellular and DNA damage. But relatively higher amounts of 4-OHE and 16-OHE can be toxic and increase the risk of cervical dysplasia, cervical cancer4 and breast cancer.5
In Phase II detoxification, methylation of 2-OHE and 4-OHE via the enzyme COMT is important for decreasing the toxicity of these metabolites. Methylation can be supported with methyl donors such as methionine, vitamin B6, vitamin B12, folate, betaine, choline and magnesium. These methyl donors are also used for alcohol metabolism and can help protect against alcohol-induced liver damage.6 Therefore you can run through these nutrients much faster if your body needs them for multiple purposes. As well, increased estrogen means these phase I and II pathways can get backed up since there’s an increased need for these metabolic and detoxification enzymes. Some individuals may have abnormal function of these particular enzymes which could slow down these pathways, leaving them even more backed up and increasing the body’s concentration of estrogens and estrogen metabolites.
Health Risks of Alcohol-Induced Hyperestrogenism
We know there is an association between estrogen levels and breast cancer development, meanwhile, excessive alcohol consumption is also linked to breast cancer development.7 The effects described above may help explain how these overlap. In one study, those who drank seven or more alcoholic beverages per week over a year had a 47% higher breast tissue density compared to those who had less than one drink per week.7
Increasing estrogen levels can also negatively impact estrogen-dominant disorders such as endometriosis and fibroids. Higher aromatase activity and increased estrogen can lead to heavier menstrual bleeding and menstrual pain in these disorders in addition to worsening the condition by feeding the abnormal lesion growth.
Due to the effects on estrogen and other sex hormones such as testosterone and progesterone, alcohol consumption can also affect embryo quality and overall fertility. One study found that having three or more drinks per week during the luteal phase of the menstrual cycle decreased the chance of a pregnancy that cycle and for each day of binge drinking, the likelihood of pregnancy that cycle decreased by 19 to 41%.8
Overall, the amount of alcohol a person consumes will affect the magnitude of hormonal changes. A person’s unique genetic profile, including how well certain enzymes function, and the state of hormone receptors, can also influence outcomes. What we can say is that alcohol intake does have an effect on estrogen and typically increases it.
Supporting healthy liver detoxification of estrogens, as well as reducing the effect of aromatase, may help reduce health risks. This includes phase I supporters such as the compound DIM (3’3-Diindolylmethane) found in cruciferous vegetables like broccoli, which favours the safer 2-OHE pathway, as well as compounds that support phase II and downstream detoxification pathways that allow us to eliminate excess estrogen metabolites…and maybe avoid regular alcohol intake, especially if you have an excess-estrogen disorder or are trying to conceive.
References
- Finn DA. (2020). The Endocrine System and Alcohol Drinking in Females. Alcohol Res. 40(2):02
- Hartman TJ, Sisti JS, Hankinson SE, et al. (2016). Alcohol Consumption and Urinary Estrogens and Estrogen Metabolites in Premenopausal Women. Horm Canc. 7:65-74
- Shufelt C, Merz CN, Yang Y, et al. (2012). Red versus white wine as a nutritional aromatase inhibitor in premenopausal women: a pilot study. J Womens Health (Larchmt). 21(3):281-4
- Sepkovic DW, Stein J, Carlisle AD, et al. (2009). Diindolylmethane inhibits cervical dysplasia, alters estrogen metabolism, and enhances immune response in the K14-HPV16 transgenic mouse model. Cancer Epidemiol Biomarkers Prev. 18(11): 2957-64
- Im A, Vogel VG, Ahrendt G, et al. (2009) Urinary estrogen metabolites in women at high risk for breast cancer. Carcinogenesis. 30(9):1532-5
- Powell CL, Bradford BU, Craig CP, et al. (2010). Mechanism for prevention of alcohol-induced liver injury by dietary methyl donors. Toxicol Sci. 115(1):131-9.
- Frydenberg H, Flote VG, Larsson IM, et al. (2015). Alcohol consumption, endogenous estrogen and mammographic density among premenopausal women. Breast Cancer Res. 17(1):103
- Anwar MY, Marcus M, Taylor KC. (2021). The association between alcohol intake and fecundability during menstrual cycle phases. Hum Reprod. 36(9):2538-2548