The most common cancer for women of all races in the United States is breast cancer. This includes both invasive and non-invasive types. It affects more than twice as many women as the second most common form, lung cancer.

It is essential that women understand how to prevent breast cancer, how to screen for it, and how to treat it if it is diagnosed.

How to Prevent Breast Cancer

*To prevent cancer, the key is to avoid risk factors and increase protective factors.

Not everything is in your control; for instance, you can’t change your age or family history. You can, however, avoid the following risk factors—and integrate the following protective factors, in order to reduce your chances of getting this disease.

Maintain a healthy weight: Obesity is associated with an increased risk of getting breast cancer. When it is diagnosed, there is a higher chance of aggressive cancer and death if the patient is obese. This may be due to the fact that fat produces and secretes substances, including hormones and growth factors, that affect breast tissue.

Exercise regularly: Getting regular exercise is a protective factor. It reduces your chances of getting breast cancer if you’ve never been diagnosed, especially for post-menopausal women. If you have been diagnosed and treated, exercise lowers your chances of it coming back.

Get enough sleep: There is an association between lack of sleep and some of the most common cancers, including breast cancer. The reason for this association is not well-understood, but it may be due to the reparative effects that sleep has on the body. Sleep is a protective factor, so be sure to get sufficient sleep so that you feel well-rested the next day.

Minimize (or eliminate) alcohol consumption: Excess drinking (for women, more than seven drinks per week or more than one drink per day) significantly increases your chances of getting breast cancer. In fact, even drinking small amounts of alcohol causes a small increase in risk; worse, the more you drink, the higher your risk. Alcohol is a risk factor for breast cancer because it has an effect on estrogen metabolism and increases the amount of estrogen in the body. Estrogen feeds hormone-receptive breast cancers.

Avoid carcinogens: Carcinogens can lead to cancer and, therefore, are risk factors to be avoided. The number of potential carcinogens in our environment is quite large (the American Cancer Society displays a thorough list here). Some specific carcinogens to avoid for breast cancer include alcohol (see above), combination birth control pills, hormone replacement therapy, chemicals in vehicle exhaust, flame retardants, stain-resistant textiles, paint removers, and disinfection by-products in drinking water.

Avoid unnecessary radiation: Imaging studies like CT scans, PET scans, and X-rays are unavoidable in modern medicine. You can, however, minimize their unnecessary usage and only get tests that are needed. This is important because exposure to radiation is a risk factor for getting breast cancer.

Breastfeed your babies: Breastfeeding isn’t just a smart choice for babies; it has also been shown to significantly reduce the risk of breast cancer in women who breastfeed. One of the reasons for this finding is that breastfeeding delays the onset of menstruation after childbirth, thus reducing a woman’s lifetime exposure to estrogen. Breastfeeding for longer periods provides even greater protection.

How to Screen for Breast Cancer

Breast examination: Women should be regularly performing self-examination of the breasts at home. If you are in your reproductive years, do it around the same time each month so that you become familiar with how your breasts feel during that point in your menstrual cycle. Examine each breast and the armpit area with the opposite hand while raising the arm on the same side of the breast over your head. Use a combination of gentle and firm touch. Bring any lumps or hard spots to the attention of your doctor, who can also perform a physical examination in the office.

Mammograms: Regular mammograms are recommended for women beginning at age 45, or at age 40 if desired by the patient. This is a screening test that is essentially an X-ray of both breasts. Mammograms can detect suspicious lesions including tumors and clusters of calcium. They have been found to reduce the mortality from breast cancer, likely because they help catch cancer at an earlier stage. If you are a woman age 45 or older, be sure to get regular mammograms. Talk to your doctor about the risks and benefits if you are between 40 and 44.

Magnetic resonance imaging: Breast MRI is not done on patients with an average risk of breast cancer but is instead generally reserved as a screening test for patients who are at higher risk. These include women with BRCA1 or BRCA2 mutations or who have a parent, sibling or child with breast cancer. If you are at higher risk of breast cancer, you may benefit from regular screening with both mammography and MRI.

How to Treat Breast Cancer

Breast biopsy: You have gotten a biopsy, and the report comes back: you have breast cancer! There are some questions you need to ask. Is the cancer invasive or non-invasive? What is the grade? Does it express estrogen and progesterone receptors? What about HER2? These questions should all be answered on the pathology report.

Surgery: Surgical removal of the cancer is critical to your treatment. The surgeon will want to make sure that all the cancer is removed and the margins are clear. Some patients will choose to undergo mastectomy or even a double-mastectomy, with the removal of both cancerous and non-cancerous breast tissue. You will need to decide what is the best choice for you.

Radiation therapy: Radiation therapy is a localized treatment that may be recommended after surgery to eradicate any remaining tumor cells in the breast or armpit area.

Chemotherapy: One or more chemotherapy drugs may be used to eliminate any remaining cancer cells or to prevent the cancer from coming back. Especially if you have more advanced disease, such as spread to other parts of your body, you will want to consider chemotherapy.

Hormonal therapy: Hormone therapy is an important part of treatment for breast cancers that express estrogen receptor and progesterone receptor. There are several kinds of therapies; they work by reducing the amount of estrogen in the body or by blocking the effects of estrogen on cancer cells.

By following the above recommendations, women can take charge of their health by taking concrete steps to lower their chances of getting breast cancer, understand how to screen for it (especially if they are over 40 years of age), and understand how to treat it if they are diagnosed.