Healthy Lifestyle for People Who’ve Had Breast Cancer

We don’t fully understand how diet is related to survival after breast cancer.

Women who are overweight or obese (and those who gain weight) after a breast cancer diagnosis have worse survival than those who are lean [160-167]. However, there’s no specific type of diet, dietary pattern or nutrient proven to be linked to breast cancer survival.

Some dietary factors have been studied more than others. These include carotenoids, dietary fat and soy (see below).

A healthy diet is important for everyone, including people who’ve had breast cancer.

Learn more about diet and breast cancer.

Healthy diet

People who’ve had breast cancer can benefit from the same healthy diet recommended for everyone.

This diet (outlined below) promotes overall health and may be linked to a lower risk of some cancers and other conditions such as heart disease, diabetes and osteoporosis.

• Reach and maintain a healthy weight. People who’ve had breast cancer and are overweight or obese should limit high-calorie foods and beverages and increase physical activity to help with weight loss.
• Eat at least 2½-3 cups of vegetables and 1½-2 cups of fruit every day. Eat a variety of vegetables and fruits. Include dark green, red and orange vegetables as well as legumes, such as beans, lentils, peas and soy foods.
• Choose 100% whole grain foods such as 100% whole grain breads and cereals, brown rice, millet and quinoa.
• Eat “good” fats (polyunsaturated and monounsaturated fats). These are found in foods such as olive and avocado oil, nuts and natural nut butters, olives and avocados.
• Limit or avoid red meat and processed meat, such as beef, bacon and sausage. Choose chicken, fish or beans more often for good sources of protein.
• Limit or avoid sugar-sweetened beverages. Choose water or unsweetened beverages more often.
• Limit or avoid highly processed foods and refined grain products, such as fast food, ready-to-heat foods, packaged snack foods and candy.
• Avoid alcohol. For those who choose to drink alcohol, limit to less than 1 drink a day for women and fewer than 2 drinks a day for men.

Adapted from the American Cancer Society and the American Society of Clinical Oncology’s Breast Cancer Survivorship Care Guidelines [1].

A registered dietitian may use the term “nutrient density” when discussing diet. This is the balance of nutrients and calories in the foods and beverages you eat and drink. Nutrient dense foods have vitamins, minerals and other nutrients, with limited saturated fat, added sugars and salt.

Fred Hutchinson Cancer Center’s Cook for Your Life website offers recipes, cooking videos and nutrition and health information in English and Spanish.

Carotenoids (found in fruits and vegetables)

Carotenoids are natural orange-red food pigments found in fruits and vegetables such as melons, carrots and sweet potatoes. Many carotenoids, such as beta-carotene, are antioxidants and can be converted into vitamin A in the body.

Researchers can study carotenoids by measuring levels of carotenoids in the blood or by estimating carotenoids in a person’s diet.

Data on carotenoids and breast cancer survival are limited.

Studies of blood levels of carotenoids

One study of more than 3,000 breast cancer survivors found those with higher blood levels of carotenoids had better disease-free survival (survival without a breast cancer recurrence) than those with lower levels [171].

Studies of dietary intake of carotenoids

One study of more than 4,000 breast cancer survivors found breast cancer mortality (death from breast cancer) and overall mortality (death from any cause) were the same for survivors with a high dietary intake of carotenoids as for those with a low dietary intake [172].

Note of caution on carotenoid supplements

Carotenoid supplements, such as beta-carotene supplements, may have some health risks.

A few studies have found taking a daily beta-carotene supplement may be linked to an increased risk of lung cancer and early death in smokers [173-174].

Fruits and vegetables are the best sources of carotenoids (rather than supplements) and are part of a healthy diet.

Dietary fat

Researchers are studying whether eating a low-fat diet after a breast cancer diagnosis is linked to improved survival. Findings are mixed.

Most studies (including 2 randomized controlled trials) show no difference in survival between women who ate a diet low in fat after a breast cancer diagnosis and women who ate a diet high in fat after diagnosis [172,175-177]

However, findings the Women’s Health Initiative Dietary Modification Trial (a randomized controlled trial) showed women who reduced dietary fat after a breast cancer diagnosis had better survival than women who did not reduce dietary fat [178]. Researchers are studying whether the improved survival in the low-fat diet group may have been due to weight loss.

For a summary of research studies on dietary fat and breast cancer survival, visit the Breast Cancer Research Studies section.

Soy

Soy foods

Studies suggest eating moderate amounts of soy foods is safe for breast cancer survivors [179-182].

Some studies have found eating a diet high in soy may be linked to a decreased risk of breast cancer recurrence and breast cancer mortality (death from breast cancer) [179-181]. Most of these findings are from studies of Asian women, who tend to eat more soy throughout their lives (starting early in life) compared to other women [180,183-184].

One analysis combined data from 3 large studies of breast cancer survivors from Asian and Western countries. It found women who ate at least 10 mg of soy per day after a breast cancer diagnosis had a 25% lower risk of breast cancer recurrence compared to those who ate little or no soy [180].

Eating soy isn’t recommended as a way to try and lower the risk of breast cancer recurrence.

Questions remain about study findings on soy and breast cancer survival. For example, women who regularly eat soy tend to be healthier than those who don’t, which may account for the survival benefit shown in some studies [180].

Soy supplements

Most studies looking at soy and breast cancer have focused on soy foods rather than soy supplements [179-184].

In the lab, researchers can separate soy proteins into individual compounds, called isolates. Individual isolates don’t occur in nature.

This is similar to other supplements, such as vitamin A. While many natural things contain vitamin A, pure vitamin A (alone) is not found in nature. Isolates, such as pure vitamin A, can only be created in a lab. Because soy supplements are created in a lab, they may contain individual soy protein isolates.

Some lab studies of cells have shown soy protein isolates may increase cancer growth [185-186]. So, soy supplements are not recommended for people who’ve had breast cancer.

Soy and hot flashes

Soy foods and soy supplements have been suggested as ways to relieve hot flashes.

Findings from randomized controlled trials are mixed. Some show soy can reduce hot flashes, while others do not [87-90].

Learn about ways for women who’ve had breast cancer to treat hot flashes and other menopausal symptoms.

Organic foods

According to the American Cancer Society’s Diet and Physical Activity Guidelines for Cancer Prevention, research shows organic foods are no more nutritious or better for you than foods farmed by conventional methods [159].

Learn more about organic foods.

*Please note, the information provided within Komen Perspectives articles is only current as of the date of posting. Therefore, some information may be out of date.