The results of the UK’s Million Women Study is questioning what many women thought they knew about alcohol consumption (AC).
This major study links even low-to-moderate AC to increased risk of breast cancer and several other cancers. Most women in the United Kingdom and the United States who drink, drink amounts classified as low-to-moderate.
The study concludes that AC accounts for approximately 11 percent of breast cancer in the United Kingdom. This is strikingly similar to the conclusions of a Policy Report released this year by the American Institute for Cancer Research linking 11 percent of breast cancer in the U.S. to AC.
The Million Women Study followed 1.3 million middle-aged women for seven years. The large number of women in the study gives its conclusions strength and allowed researchers to compare cancer risk among a range of intake levels, from occasional to frequent consumption.
Compared to women who drink no more than 2 standard drinks per week, 7 to 14 drinks per week increased breast cancer risk by 13 percent. Above seven to 14 drinks per week is beyond the one drink per day definition of moderate drinking for women. But even 3 to 6 drinks per week , classified as low to moderate, increased risk 8 percent. This rise in breast cancer risk may seem small, but because it is the most common cancer among American women, except for skin cancers, even a small percentage change can affect many women.
In the U.S., one standard drink (5 ounces of wine, 12 ounces of beer, or one-and-a-half ounces of 80-proof spirits) contains 12 to 15 grams of alcohol. This new study found that each additional ten grams daily increased women’s risk of cancers of the mouth and throat by 29 to 44 percent. Risk of liver cancer increased 24 percent, esophageal cancer 22 percent and that of breast cancer 12 percent.
The large study size also allowed researchers to look separately at smokers and nonsmokers. Previous research showing an interaction between tobacco and alcohol was clearly demonstrated. The dramatic increase in cancers of the mouth and throat linked to AC was strongly tied to smoking, perhaps because alcohol seems to increase the ability of tobacco’s carcinogens to enter and damage cells. Among nonsmokers, alcohol showed little effect on mouth and throat cancers.
Red wine drinkers may have hoped that laboratory studies of an antioxidant compound called resveratrol found in red wine might make it protective. However, this study shows wine is no different in increasing cancer risk.
Although the conclusions from this Million Women Study may prompt some women to give up completely, the study also found that women consuming up to two drinks per week showed no significant difference in cancer risk compared to those who identified themselves as nondrinkers.
For each woman, impact on risk varies with personal and family history, diet and overall lifestyle. Some evidence suggests that up to one drink per day may be heart-healthy for women. Yet other steps to promote heart health, weight control, daily physical activity and a mostly plant-based diet low in saturated fat, also reduce the risk of cancer.
While avoidance could prevent about 11 percent of breast cancer in U.S. women, regular physical activity and weight control could each prevent 17 percent of cases. In fact, reaching and maintaining a healthy weight could prevent about 20 percent of seven types of weight-related cancers, including breast cancer, pancreatic cancer, and colorectum cancer.
References:
1. American Institute for Cancer Research.
2. Image by baltazarart.
