Breast Cancer: The Food and Fitness Connection

October 3, 2011

by Karen Sabbath, MS, RD, CSO

"What can I eat to prevent my breast cancer from coming back?" This is a question asked by many breast cancer patients. Unfortunately, the answer is unclear. Clinical trials have fallen short in demonstrating a direct connection between what you eat and your chances of developing breast cancer, or a recurrence (having your cancer come back). However, we do know that in populations who eat a plant-based Asian or Mediterranean diet, there appears to be a lower incidence of breast cancer. Does this mean that you can toss out the brown rice and start shoveling in chips and dip? Absolutely not. There ARE many things you can do to lower your risk of getting breast cancer or a recurrence, and nutrition plays a big part.

Here's what we do know: 85% of women diagnosed and treated for breast cancer will survive. As survivors, they will be at risk for long term chronic diseases including heart disease, osteoporosis, diabetes and hypertension. We know that nutrition plays a significant role in the management of these diseases. This means that following a plant-based diet should be an integral part of a healthy lifestyle. For women who want to be proactive, there are many lifestyle recommendations that can play a role in breast cancer prevention.

The 2 most important things that women can do to reduce their risk of breast cancer or a recurrence is to try and reach an ideal weight and exercise on a regular basis.

Getting your weight into the normal range can be a challenge, especially for newly menopausal and postmenopausal women. As women age, their metabolic rates slow down, so the weight comes on faster than it comes off. At the rate of 5 -10 pounds a year, a weight gain of 20-30 lbs in a few years is not uncommon. In a study sponsored by the American Cancer Society, women who gained 21-30 pounds after the age of 18 were 40% more likely to get breast cancer than their normal weight counterparts. The higher the weight gain, the higher the risk.

There are many reasons that being overweight or obese increases the risk of a recurrence.

The estrogen connection: Fatty tissue (also called adipose tissue) produces estrogen. In women with estrogen-receptor positive (ER+) breast cancer, the goal is to minimize exposure to estrogen in order to prevent the breast cancer cells from growing. Women who are significantly overweight may be fueling their breast tissue with estrogen on a daily basis, potentially increasing their risk of recurrence. This is true even if they take medications to block estrogen production (Femara, Aromasin, Arimidex) or protect breast cancer cells from estrogen (Tamoxifen)

Haywire Hormones: Too much body fat interferes with the internal regulation of certain hormones that can lead to chronic diseases like heart disease, diabetes and even certain cancers (including breast cancer).

Insulin Resistance: Insulin is a hormone that regulates blood sugar levels. In most people, eating a meal containing carbohydrates results in an increase in blood glucose/sugar. Typically, the pancreas produces insulin in response, which transports the glucose to the cells and tissues that need it for fuel or storage. In insulin resistance, the cells in the body ignore the insulin, and the pancreas keeps making more and more. Too much insulin can result in excessive weight gain and increased inflammation. It is felt that inflammation is how many diseases, including cancer, begin. Obesity causes increased insulin production.

How do you know if you are overweight? You can calculate your Body Mass Index, or BMI, which is a ratio of weight and height. If your BMI is greater than 25, your weight is too high. If it is over 30, it falls into the obese range.

For more information about calculating your BMI, go to http://www.nhlbisupport.com/bmi/

Reaching a healthy weight is one piece of the puzzle. How do you do that? Eating a healthy plant-based diet plays an enormous role in losing weight. But in order to take off the pounds, you need to burn more calories. And that is where the exercise piece fits in.

Exercise has been shown to be an independent factor in reducing the risk of cancer and/or cancer recurrence.

Research has established that regular physical activity helps to maintain healthy bones, muscles and joints, reduce the risk of high blood pressure and diabetes and promote psychological well being. In addition, exercise lowers insulin and other inflammatory hormones, lowers the amount of body fat, and therefore estrogen, and helps people lose weight, all of which contribute to a lower risk of developing breast cancer. In fact, the latest research has provided convincing evidence that moderate physical activity, just 150 minutes a week, or 30 minutes 5 days a week can reduce the risk of breast cancer by 30-50%, and reduce the risk of a recurrence or death from breast cancer.

Other nutrition related suggestions that may lower your risk include:

Limit your alcohol intake to no more than 1 drink a day. Remember that 1 drink=1 ½ oz. hard alcohol, 6 oz. wine or 12 oz. beer.
Lower your intake of animal fat, which is high in saturated fat and potential cancer causing substances. Even though a diet very low in saturated fat only showed a slight decrease in the risk of invasive breast cancer, it decreases the risk of many other chronic diseases
Lower your intake of refined sugars, which can add empty calories AND increase insulin production

We all know that there are no guarantees in life. All we can do is try our best to lead a healthy life by doing the things that are felt to make a difference. If you try to modify your lifestyle by eating a diet that is rich in fruits, vegetables, whole grains, healthy fats and lean proteins, mostly from plants, and getting your weight into a healthy range, with regular exercise, you will be maximizing your odds for a long and healthy future.

Delicious recipe:

WATERMELON GAZPACHO
Serves 6-8

Ingredients:

3 c. chopped seedless watermelon
3 c. pureed seedless watermelon
3/4 c. chopped red onion
1 c. diced red tomato
1 c. finely diced cucumber, seeded and peeled
6 TBSP chopped fresh chives (you can substitute finely chopped scallions)
1/4 cup rice vinegar
1 c. OJ
3 TBSP vegetable oil (canola)
1 tsp Kosher salt or more to taste (I usually start with 1/2 tsp and add as needed)
1 TBSP or less sugar

Directions:
Combine all ingredients! Chill well before serving.