Serving size on label not always healthy choice

Q: Does the serving size listed on a food label signify the amount that is healthy for me to eat?

A: No, not always. The serving size on the label provides a reference amount for interpreting the other information on the label's Nutrition Facts panel. It's the first item you should look at to see what that food is contributing to your overall eating.

Measure the amount you usually eat and compare to what is on the label. For example, if the serving size for ice cream lists a half-cup, but you eat one cup, if the label says 140 calories, you are getting double that: 280 calories. On the other hand, if you have one slice of whole-wheat bread and the label lists a serving as two slices, or a half-cup of frozen broccoli instead of the one cup that is a standard label serving, then you are getting half as many of the listed calories, as well as fiber and vitamins.

You can also use the serving size to compare nutritional differences between similar foods. For example, if you're looking for a cereal high in fiber, when you can compare the cereal's labels to see which one has more, make sure you are comparing similar amounts.

How much you should eat for a healthy portion depends upon your nutrient needs based on your age, gender, physical activity, overall calorie needs and more. Even for two people with similar overall needs, a portion size that works well for one person may differ from the best portion for someone else if they differ in the other food choices and amounts they select.

Q: Is it true that breast cancer survivors risk developing or worsening lymphedema if they do strength-training exercises with their arms?

A: Exercise, especially of the arms, used to be considered too risky for breast cancer survivors due to fears of lymphedema, which is an accumulation of lymph in the soft tissue with swelling. This condition is not usually life-threatening, but it can seriously impact quality of life, with decreased flexibility, difficulty fitting in clothes, feelings of heaviness and increased risk of recurrent skin infections. Yet lack of exercise can begin a cycle of physical decline with serious consequences; emerging research now suggests that the best course is safe exercise rather than no exercise.

Lymphedema, which can occur within days or years after cancer or its treatment, blocks flow in the lymph system that transports lymphocytes (white blood cells) and other infection-fighting cells throughout the body, resulting in swelling where the fluid accumulates. For breast cancer survivors, this tends to involve the arms and/or hands. As many as one in three women whose breast cancer surgery includes full removal of lymph nodes in the underarm area (axillary node dissection) experience lymphedema, and radiation therapy to the area may lead to its development, too.

Once lymphedema develops, it doesn't go away, but some steps may make it easier to live with or possibly prevent it, according to the National Lymphedema Network. Avoid extreme exercise of the arm that could potentially be affected because it can promote inflammation or injury. Current studies in breast cancer survivors suggest that starting with low intensity upper-body exercise and progressing slowly does not increase onset of lymphedema and is better than no upper arm exercises as long as any symptoms that develop are monitored closely and treated.

The National Comprehensive Cancer Network guidelines recommend that patients with or at risk for lymphedema be evaluated by a certified lymphedema therapist to ensure it is safe to exercise. Cancer survivors who have lymphedema should wear a garment know as a lymphedema sleeve during all exercise that uses the affected limb, according to the National Cancer Institute. Those without lymphedema do not need to wear this while doing exercise. If you are a survivor and it's unclear whether you have lymphedema and what exercises to do, talk with your physician and health care team.

Resources to help you find a certified lymphedema include the Lymphology Association of North America and the National Lymphedema Network.

• The American Institute for Cancer Research (AICR) is the cancer charity that fosters research on the relationship of nutrition, physical activity and weight management to cancer risk, interprets the scientific literature and educates the public about the results.