Ways to cut calories from that piece of cake

Q. If I skip the frosting on cake, will I remove most of the calories?

A. Calorie content of cake and frosting vary substantially depending how they're made, but you may avoid about a third of the calories by skipping the frosting.

Some frostings are primarily powdered sugar, while others contain substantial amounts of butter or shortening, which increase calories significantly. Frosting alone can add anywhere from 150 to 400 calories on one slice of cake.

When you make cake, leaving it unfrosted and simply sprinkling it with a dusting of powdered sugar will reduce calories and still be delicious. Or top the cake with fruit, and pass extra fruit for people to top their own slice, for sweetness with lots of nutrients.

For a typical 9-inch cake cut in 12 slices, even without frosting each slice still has more than 250 calories. So don't think of it as "diet food" just because it's unfrosted or use that to justify having an extra slice.

With or without frosting, another major influence on calorie content is portion size. For a typical cake, cutting portion size in half will reduce calories even more than omitting the frosting. If all you want is a sweet taste, you may be surprised how satisfied you feel with just two or three bites eaten slowly and savored; then put your plate away.

If you only have cake occasionally, it may not be a big influence on your weight. But if your workplace, family or social group serves cake frequently, shifting how much or what part you eat, and even how often you eat any, could be an important part of your weight control strategy.

Q. Do sweet potatoes reduce breast cancer risk? I've heard they do, but other reports say they increase risk. What's up?

A. Sweet potatoes can be a delicious part of an overall diet linked with lower risk of breast cancer. They are good sources of beta-carotene and vitamin C, nutrients that seem to reduce overall cancer risk.

Although a few studies have linked greater beta-carotene consumption or highest blood levels of beta-carotene with reduced risk of breast cancer, these and other studies also link higher dietary and blood levels of other carotenoids with reduced risk in some women. This shifts the message to encouraging an overall healthy diet with at least five servings a day of a wide variety of vegetables and fruits, rather than simply beta-carotene itself.

Beta-carotene supplements are not associated with any reduction in risk of breast cancer or other cancers. So enjoy sweet potatoes, as well as other top sources of beta-carotene (carrots, pumpkin, winter squash, spinach, kale and cantaloupe) knowing you're getting a variety of health-promoting nutrients.

And remember to make them part of a diet that helps you reach and maintain a healthy weight, which is one of the most strongly supported steps to protect against breast cancer. That means watching your portions and avoiding toppings for the sweet potatoes that add a lot of excess sugar or fat.

Your question about risk probably stems from Internet postings that sweet potatoes pose a breast cancer risk because they contain phytoestrogens (plant estrogens), but research does not support such a worry.

• American Institute for Cancer Research