Even a small amount of alcohol increases breast cancer risk


We hear constantly that moderate consumption of alcohol, especially red wine, is beneficial for cardiovascular health. However, when it comes to cancer risk, any amount of alcohol is risky. A 2014 report by the International Agency for Research on Cancer concluded that there is no safe amount of alcohol when it comes to cancer risk.1, 2 Alcohol is now considered a cause of cancers of the mouth, pharynx, larynx, esophagus, colorectum, breast, and liver, and is linked to other cancers too.1, 3, 4  

Isn’t red wine good for heart health?

Some of red wine’s benefit is thought to be due to resveratrol, a phytochemical in grape skins that has anti-inflammatory and antioxidant effects that may help protect against cardiovascular disease (CVD).5  However, the majority of the reduction in CVD risk is actually from the inhibition of blood clotting by the alcohol. At this point in time it is unknown whether resveratrol provides additional benefits over the anti-coagulation effects.6 Plus grapes, raisins, blueberries, cranberries, and peanuts also contain resveratrol – red wine is not the exclusive source of this phytochemical. You will get much more health benefit from a cardio-protective diet of phytochemical-rich plant foods than you will from an occasional glass of red wine.

Plus, the blood thinning effects from daily alcohol use are only an advantage if you are eating very unhealthfully and at high risk of a clot because of your poor diet.  When you eat a Nutritarian diet, you are already protected against heart disease, and the blood thinning effects of aspirin and alcohol are not a useful benefit anymore.  In other words the risks (cancer and hemorrhagic stroke) become higher than the cardiovascular benefits, which disappear with healthy eating.  

Regardless of whether resveratrol provides cardiovascular benefit, it is incorrect to think you are doing something good for your health when you drink red wine. Even light drinking increases the risk of several different types of cancer. After alcohol is ingested, the body metabolizes it into a carcinogenic compound called acetaldehyde. The evidence suggests that even light drinking (less than 1 drink/day) or using alcohol-containing mouthwashes may be risky.7-9 Additional carcinogenic substances are present in alcoholic beverages, such as arsenic, benzene, cadmium, formaldehyde, lead, ethyl carbamate, acrylamide, and aflatoxins.1

Alcohol’s effects are greater in women than men

This is especially important for women to know, because there are gender differences in alcohol metabolism. The same amount of alcohol causes a greater blood alcohol level to be reached in females compared to males of the same weight.10, 11  Alcohol consumption may also increase estrogen levels, which could further increase the breast cancer risk associated with alcohol consumption.12  

Less than one drink a day increases breast cancer, and more drinking amplifies the risk

Women in the range of 3-6 alcoholic drinks weekly were found to have a 15% increase in breast cancer risk compared to non-drinkers, and 3-4 drinks per week is also associated with higher rates of breast cancer recurrence after diagnosis.13-15 Increased cancer risk due to light alcohol intake is not limited to breast cancer.

A meta-analysis of studies on the relationship between light drinking and cancer risk estimated that light alcohol drinking is responsible for 5,000 deaths from oral and pharynx cancers, 24,000 deaths from esophageal squamous cell carcinoma, and 5,000 deaths from breast cancer worldwide each year. Importantly, the researchers found that this risk was dose-dependent: meaning the more you drink, the greater the risk.16  For health and longevity, the safest choice is to not drink any alcohol.

 

 
References
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  2. Rehm J, Sield K: Alcohol consumption. In World Cancer Report 2014. pp. 96-104; 2014:96-104.
  3. Baan R, Straif K, Grosse Y, Secretan B, El Ghissassi F, et al. (2007) Carcinogenicity of alcoholic beverages. Lancet Oncol, 8:292-293.
  4. Connor J (2016) Alcohol consumption as a cause of cancer. Addiction.
  5. Higdon J: Resveratrol. In An Evidence-Based Approach to Dietary Phytochemicals. 2006
  6. Saremi A, Arora R (2008) The cardiovascular implications of alcohol and red wine. Am J Ther, 15:265-277.
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  8. Lachenmeier DW, Gumbel-Mako S, Sohnius EM, Keck-Wilhelm A, Kratz E, et al. (2009) Salivary acetaldehyde increase due to alcohol-containing mouthwash use: a risk factor for oral cancer. Int J Cancer, 125:730-735.
  9. Lachenmeier DW, Kanteres F, Rehm J (2009) Carcinogenicity of acetaldehyde in alcoholic beverages: risk assessment outside ethanol metabolism. Addiction, 104:533-550.
  10. Schardt D: Why alcohol affects women more than men. In Nutrition Action; 2017.
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  12. Hartman TJ, Sisti JS, Hankinson SE, Xu X, Eliassen AH, et al. (2016) Alcohol Consumption and Urinary Estrogens and Estrogen Metabolites in Premenopausal Women. Horm Cancer, 7:65-74.
  13. Boyle P, Boffetta P (2009) Alcohol consumption and breast cancer risk. Breast Cancer Res, 11 Suppl 3:S3.
  14. Kwan ML, Kushi LH, Weltzien E, Tam EK, Castillo A, et al. (2010) Alcohol consumption and breast cancer recurrence and survival among women with early-stage breast cancer: the life after cancer epidemiology study. J Clin Oncol, 28:4410-4416.
  15. Chen WY, Rosner B, Hankinson SE, Colditz GA, Willett WC (2011) Moderate alcohol consumption during adult life, drinking patterns, and breast cancer risk. JAMA, 306:1884-1890.
  16. Bagnardi V, Rota M, Botteri E, Tramacere I, Islami F, et al. (2013) Light alcohol drinking and cancer: a meta-analysis. Ann Oncol, 24:301-308.