If you have (or have had) breast cancer, you probably want to know if there are things you can do (aside from your treatment) that might lower your risk of the cancer growing or coming back, such as getting or staying active, eating a certain type of diet, or taking nutritional supplements. Fortunately, breast cancer is one of the best studied types of cancer in this regard, and research has shown there are some things you can do that might be helpful.
Staying as healthy as possible is more important than ever after breast cancer treatment. Controlling your weight, being physically active, and eating well may help you lower your risk of breast cancer coming back, as well as help protect you from other health problems.
If you have had breast cancer, getting to and staying at a healthy weight might help lower your risk. A lot of research suggests that being overweight or obese (very overweight) raises the risk of breast cancer coming back. It has also been linked with a higher risk of getting lymphedema, as well as a higher risk of dying from breast cancer.
However, there is less research to show whether losing weight during or after treatment can actually lower the risk of breast cancer coming back. Large studies are now looking at this issue. This is complicated by the fact that many women gain weight (without trying) during breast cancer treatment, which itself might increase risk.
Of course, for women who are overweight, getting to a healthy weight can also have other health benefits. For example, weight loss has been shown to improve quality of life and physical functioning among overweight breast cancer survivors. Getting to a healthy weight might also lower your risk of getting some other cancers (including a new breast cancer), as well as some types of chronic diseases.
Because of the possible health benefits of losing weight, many health care providers now encourage women who are overweight to get to and stay at a healthy weight. Even losing a few pounds may be helpful. Still, it’s important to discuss this with your doctor before trying to lose weight, especially if you are still getting treatment or have just finished it. Your health care team can help you create a plan to lose weight safely.
Among breast cancer survivors, studies have found a consistent link between physical activity and a lower risk of breast cancer coming back and of dying from breast cancer, as well as dying of any cause. Physical activity has also been linked to improvements in quality of life, physical functioning, and fewer fatigue symptoms.
It’s not clear exactly how much activity might be needed, but more seems to be better. More vigorous activity may also be more helpful than less vigorous activity. But further studies are needed to help clarify this.
In the past, breast cancer survivors with lymphedema were often advised to avoid certain arm exercises and vigorous activities. But studies have found that such physical activity is safe when done the right way. In fact, it might actually lower the risk of lymphedema, or improve lymphedema for women who already have it.
As with other types of lifestyle changes, it’s important to talk with your treatment team before starting a new physical activity program. This will likely include meeting with a physical therapist as well. Your team can help you plan a safe and effective program.
Most research on possible links between diet and the risk of breast cancer coming back has looked at broad dietary patterns, rather than specific foods. In general, it’s not clear if eating any specific type of diet can help lower your risk of breast cancer coming back.
Studies have found that breast cancer survivors whose eating patterns include more vegetables, fruits, whole grains, chicken, and fish tend to live longer than those who eat more refined sugars, fats, red meats (such as beef, pork, and lamb), and processed meats (such as bacon, sausage, luncheon meats, and hot dogs). But it’s not clear if this is due to effects on breast cancer or possibly to other health benefits of eating a healthy diet.
Two large studies (known as WINS and WHEL) have looked at the effects of lowering fat intake after being diagnosed with early-stage breast cancer. One study found that women on a low-fat diet had a small reduction in the risk of cancer coming back, but these women also lost weight as a result of their diet, which might have affected the results. The other study did not find a link between a diet low in fat and the risk of cancer coming back.
Many women have questions about whether soy products are safe to eat after a diagnosis of breast cancer. Soy foods are rich sources of compounds called isoflavones that can have estrogen-like properties in the body. Some studies have suggested that soy food intake might lower the risk of breast cancer coming back, although more research is needed to confirm this. While eating soy foods doesn’t seem to pose a risk, the evidence regarding the effects of taking soy or isoflavone supplements, which often contain much higher levels of these compounds, is not as clear.
The links between specific types of diets and breast cancer coming back are not certain, but there are clearly health benefits to eating well. For example, diets that are rich in plant sources are often an important part of getting to and staying at a healthy weight. Eating a healthy diet can also help lower your risk for some other common health problems, such as heart disease and diabetes.
Women often want to know if there are any dietary or nutritional supplements they can take to help lower their risk. So far, no dietary supplements (including vitamins, minerals, and herbal products) have been shown to clearly help lower the risk of breast cancer progressing or coming back. This doesn’t mean that there aren't any that will help, but it’s important to know that none have been proven to do so.
Dietary supplements are not regulated like medicines in the United States – they do not have to be proven effective (or even safe) before being sold, although there are limits on what their makers are allowed to claim they can do. If you're thinking about taking any nutritional supplement, talk to your health care team. They can help you decide which ones you can use safely while avoiding those that might be harmful.
It’s clear that alcohol – even as little as a few drinks a week – increases a woman’s risk of developing breast cancer. But whether alcohol affects the risk of breast cancer coming back is not as clear. Drinking alcohol can raise the levels of estrogen in the body, which in theory could increase the risk of breast cancer coming back. But there is no strong evidence from studies to support this.
It is best not to drink alcohol. Women who do drink should limit it to no more than 1 drink a day to help lower their risk of getting certain types of cancer (including breast cancer). For women who have completed cancer treatment, the effects of alcohol on cancer recurrence risk are largely unknown.
Because this issue is complex, it’s important to discuss it with your health care team, taking into account your risk of breast cancer coming back (or you getting other cancers) and your risk of other health issues linked to alcohol use.
If breast cancer does return, your treatment options will depend on where it comes back, what treatments you've had before, and your current health and preferences. For more information, see Treatment of Recurrent Breast Cancer.
The American Cancer Society medical and editorial content team
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.
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Last Revised: March 16, 2022
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