The study found—drumroll, please—that women with the C-allele version of the gene 131 women total who also drank three cups or more of coffee a day and were not on hormonal birth control tended to have smaller breasts by volume.
Another article I found said that cyclic breast pain or pain related to the menstrual cycle can be made worse by certain foods and beverages and medications.
Then I got to thinking—what, besides the pregnancy itself, was different during those two times I was expecting? I was counting the days for my period to end so that I could be free of this horrible pain.
While the researchers did observe an association between smaller breast size and coffee drinkers who carry a specific genotype, they also saw an association between bigger breast size and coffee drinkers who carried the other genotype albeit less statistically significant.
So unless your boobs are perfect pyramids you should not be afraid of coffee.
You cannot establish whether breast size was affected by the coffee with a cross-sectional study at one point in time.
There are many genes in the body that will be involved in the estrogen metabolism and inflammation resulting from caffeine consumption.
Caffeine can cause breast pain If your breasts are sore or sensitive after drinking coffee it may be because of the caffeine.