Breast Health Day

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Nutrition

Avoiding Obesity and Weight Gain

Hormone Replacement Therapy (HRT) and Contraceptives

Physical Activity

Nutrition

While studies have not linked specific diets to breast cancer risk, nutrition is still important.

• Eat a well-balanced diet (daily intake of fat should not exceed 30%)

• Include fresh fruit and vegetables in your daily food choices

• Eat the right amount to maintain a healthy weight

• Limit red meat consumption

Physical Activity

Growing evidence supports that there is a protective association between physical activity and breast cancer, preferably over a lifetime, but probably beneficial even if begun after menopause.

• Regular physical activity reduces the risk of breast cancer
• Inactivity is estimated to cause 10-16% of all breast cancer cases
• Inactivity coupled with excess body weight account for nearly 33% of all breast cancer cases*

Women should:

• Stay healthy and active
• Engage in moderate exercise for at least 30-60 minutes every day

*The benefit of physical activity in reducing the chance of developing breast cancer is independent of the risk factor associated with body weight.

Avoiding Obesity and Weight Gain

Women should pursue a health strategy that will reduce the known breast cancer risk factors as much as possible, including avoiding obesity and weight gain, increasing physical activity and managing lifestyle choices. IARC estimates that excess body weight and physical inactivity account for approximately 25–33% of breast cancer cases.

Recent studies indicate that women who avoid being overweight reduce their risk of postmenopausal breast cancer. This risk is independent of the effect of physical activity. It is important for women to limit their weight gain in adult life and maintain a body mass index (BMI) of 18.5-24.9. Postmenopausal overweight /obesity is associated with an increased risk of breast cancer.

• A large amount of abdominal fat may increase the risk of breast cancer.
• Obese women tend to have more abnormal mammography readings than non-obese women

Body Mass Index (BMI)

Being overweight with a BMI of 25 or higher, or obese with a BMI of 30 or greater, points to an increased risk of developing postmenopausal breast cancer. Women who have already had breast cancer may help reduce their risk of further problems by keeping their weight within the normal range.

Hormone Replacement Therapy (HRT) and Contraceptives

Based on evidence from various studies, the Women’s Health Initiative (or www.whi.org) and the Million Women Study, there is a very clear connection between HRT and the risk of developing breast cancer. The Million Women Study found that current users of HRT at recruitment were more likely than never users to develop breast cancer (adjusted relative risk 1.66) (see Lancet 2003; 362: 419-27). The above mentioned studies indicate that the breast cancer risk increases the longer HRT is taken.

An IARC evaluation of cancer risk and HRT concluded that combined oestrogen–progestogen therapy is carcinogenic. This is based on the numerous studies consistently reporting an increased risk of breast cancer in women who currently use or have recently used combined oestrogen–progestogen therapy.

For women who do not have a history of breast cancer it is advisable to discuss the risks and benefits of taking HRT with your doctor in order to make an informed decision as to whether HRT is right for you. It is further recommended that you review your current treatments with your doctor on a regular basis to know if they are still your best option. If you opt for HRT, ask to take the lowest effective dose for the

shortest amount of time needed to treat your symptoms.

HRT is generally not recommended if you have a history of breast cancer as HRT may increase your risk of a recurrence of breast cancer (see HABITS trial). Any decision to take HRT should, therefore, be discussed in detail with your physician.

Oral Contraceptives and Breast Cancer

An IARC evaluation of the cancer risk with oral contraceptive use concluded: “There is sufficient evidence in humans for the carcinogenicity of combined oral oestrogen–progestogen contraceptives. This evaluation was made on the basis of increased risks for cancer of the breast among current and recent users only.”