It's always best to consult a doctor, and this forum can't diagnose or treat you. On the other hand, by now you might have several good clues as to what's going on.
If the lump has gotten bigger and smaller on a monthly cycle it could be a hormone-sensitive cyst. The lump you can feel under your arm could actually be a symptom of this "benign" (if uncomfortable) disease of the breast.
The good news about fibrocystic breast disease, if there is any, is that according to some of the latest
scientific evidence, from Europe, only about 1 in 20 women who gets breast cysts goes on to get breast cancer. If you go on the
studies from the US, it's 1 in 45. That's a lower risk of breast cancer than if you don't have any fibrocystic breast disease at all.
Dairy products have an ambiguous role in whether fibrocystic breast disease progresses to cancer. On the one hand, calcium from dairy products, vitamin D from dairy or daily exposure to the sun, and the proteins in milk and even the fat in butter, seem to protect against breast cancer. On the other hand, if all the milk and cream and butter is consumed along with fried foods, beer, and sugar, and if the dairy products are contaminated with pesticides, antibiotics, and hormones, the net result is a greater risk of breast cancer. Scientists have been trying to sort it all out in studies like one published last year in the
American Journal of Clinical Nutrition.
Getting your fruits and veggies has a subtle effect on your risk of breast cancer. Sometimes they help, and sometimes they don't.
If you eat a diet that's high in fat and sugar, getting alpha-carotene from foods like pumpkin and squash actually increases your risk of cancer. If you eat a diet that includes only modest amounts of meat and sugar and you get most of your fats in the form of "good fats" from nuts, seeds, and fish, then getting alpha-carotene lowers your risk of breast cancer.
(The natural vitamin E in nuts and seeds also relieves the pain and swelling of the cysts--if you use a supplement, please consider using one that contains gamma-tocopherol as well as alpha-tocopherol. I don't, by the way, sell any supplements, nor am I currently working for any manufacturer who does.)
The
finding of the scientists seems to be that if you eat healthy foods you also need to avoid the unhealthy foods.
Even if the lump doesn't get larger and smaller with monthly hormonal changes, it can still be just an infection in a pore. Over the course of a couple of months, simply drinking more water slowly helps. You drink more water, your skin is better hydrated, the more supple skin can let sebum and debris pass slowly out of the pore. That doesn't mean drinking 8 glasses of water a day will cure you, but it certainly can help.
What are the other possibilities? Lumps under the breast can be a complication of carpal tunnel syndrome, tennis elbow, or even a relatively new condition called ipod finger.
If you have recently gone swimming in the Congo, there are some parasites that could be a problem. There are also some rather nasty mosquito-borne diseases you can pick up in central America. An astonishingly large number of people in the US, in the hundreds of thousands, both men and women, have these conditions, but I won't go into detail here unless you ask.
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