Made from milk, butter is a rich dietary source of vitamin A and conjugated linoleic acid (CLA), both of which have been shown to have anticarcinogenic properties. However, butter consumption has been found to be associated with increased risks of leukemia, as well as oral, esophageal, thyroid, stomach, pancreatic, endometrial, colorectal, prostate and testicular cancer. In addition, consumption of butter (which has a high saturated fat content) has been found to be associated with increased risk of cardiovascular disease and heart attacks in women as well as in men.
Breast cancer-related effects of consuming butter
Women in the Nurses' Health Study who consumed more butter during high school were found to have a higher risk of breast cancer in adulthood. Another study found that butter consumption was associated with increased risk of recurrence of early stage breast cancer, especially among premenopausal breast cancer cases. Other U.S, Canadian and European studies have found that the use of butter in soups or sauces (i.e., boiled butter), butter at the dinner table, and butter used for frying food were associated with higher risks of breast cancer. High intake of full fat dairy products such as milk and cheese was found to be a significant factor for heightened breast cancer risk among Iranian women in one study. A 2017 study reported that high consumption of butter by rat mothers during pregnancy heightened the mammary tumor-promoting effects of gestational exposure to bisphenol A (BPA) in their offspring.
High intake of animal fats has been linked in several studies to increased breast density, a risk factor for breast cancer and its recurrence.
Ghee is a type of clarified butter used in South Asian and middle Eastern cuisine. To make ghee, the water and milk solids are removed from butter by heating to eliminate the water and straining. Consumption of ghee has been associated with cardiovascular disease in India; ghee has an even higher saturated fat content than butter. One Iranian study reported that women with the highest intake of ghee had double the risk of breast cancer as those with the lowest level of consumption.
Below are links to recent studies concerning this food. For a more complete list of studies, please click on butter.