Pam: cut to fit

Nutrition Wise

By Karen Collins, MS, RD, CDN

 

Q: Is it true that the sweetener sucralose does not affect blood sugar, although it comes from sugar?

A: Yes. Even though sucralose retains sugar’s sweet flavor, the changes in chemical structure make sucralose unavailable to body enzymes that would break it down to provide calories. In extensive testing, sucralose does not affect blood sugar or insulin levels. Sucralose offers two more advantages: First, it can be used in cooking and baking, unlike aspartame. Second, it does not have the bitter aftertaste associated with some other sweeteners. But before you fill your sugar bowl with sucralose, or any other nonnutritive sweetener, consider the facts. Only a small amount of the more than 20 teaspoons of added sugar that American eat each day comes from table sugar. Sweetened soft drinks are by far the major source of sugar in our diets. Sweetened cereals, bakery goods, and candy are also major sources. The biggest drop in sugar consumption will come if you do without these sugary foods more often or if the sugar levels of these products decrease.

Q: I read that your heart benefits from eating 25 grams of soy protein a day. How much soy is that? Is that enough for cancer protection, too?

A: You can get 25 grams of soy protein with any four of the following: ¼ cup (2 ounces) of tofu, 2 tablespoons of soy nuts, 6 ounces of soy milk, ¼ cup of edamame, or 2 tablespoons of soy butter. Soy bars, cereals and veggie burgers made with soy are also acceptable alternatives, but check the label to see how many grams of soy protein they contain. Not all the protein listed on the Nutrition Facts panel is necessarily soy protein. Although 25 grams of soy protein a day is often mentioned as the goal for heart protection, lesser amounts might convey smaller, but still real benefits. Researchers are still investigating how much soy consumption can lower cancer risk. Some scientists have reported benefits with as little as 11 grams of soy protein a day.

Q: I know nuts are nutritious, but how can I keep from gaining weight if I eat them regularly?

A: You’re right. Nuts are packed with nutrients. Just one ounce supplies two or three grams of fiber and four to seven grams of protein, similar to one-half to one slice of cheese, but with about two-thirds less saturated fat. Some nuts, like almonds, hazelnuts and peanuts, are a good source of vitamin E, while walnuts are a good source of health-promoting omega-3 fat. Unfortunately, all these benefits come along with 160 to 190 calories in a single ounce. Be smart with nuts: keep portions small and choose nuts as a substitute for some other food. A one-ounce portion is about a quarter-cup. That’s a scant handful for the average adult – the size of a golf ball. If you eat this portion of nuts instead of three or four cookies or a candy bar, you’ll actually save calories.

Q: Is BMI still considered an accurate assessment of a healthy weight?

A: Yes. But there are a few exceptions that may apply. Because muscle weighs more than fat, researchers have always warned that the Body Mass Index (BMI) overestimates body fatness in athletes with low body fat and a lot of muscle. Likewise, BMI underestimates body fat in the elderly or people who have lost a lot of muscle. Body fat can be accurately assessed by underwater weighing. Trained fitness professionals using calipers or other special equipment can also closely calculate how much body fat a person has. But in the absence of these specialized techniques, BMI has been shown to more closely represent body fatness than a simple weight measurement. Furthermore, studies show that people whose BMI classifies them as overweight experience a greater risk of cancer, high blood pressure, and high cholesterol. Because most Americans lead a lifestyle that is too sedentary, a high BMI usually comes from fat, not muscle. Thus, a BMI reading is a good place to start when determining health risks due to excess weight. By taking a waistline measurement — another easy test — you can better assess health risks from body fat. For women, a waist measurement of 35 inches or more indicates high risk. For men, the significant figure is 40 inches or more.

Q: I heard that albacore tuna is high in mercury and should be avoided. Isn’t this fish good for us?

A: Albacore (white) tuna is low in saturated fat and a good source of omega-3 fat that seems to help protect against cancer and heart disease. Albacore tuna is not as high in mercury as shark and swordfish, but tests rank it as “medium” in content, along with haddock, halibut, grouper, and several other fish. Too much mercury in food does pose health risks, especially to the nervous system of babies. Therefore, to control exposure to mercury, Food and Drug Administration (FDA) officials recommend that women who are pregnant, breastfeeding, or who might become pregnant limit albacore tuna to one serving a week. These women should restrict their total consumption of all fish and shellfish each week to 12 ounces. Other adults may prefer to do the same because a few studies suggest a link between excess mercury in the diet and heart risks. But for everyone except these women, current official recommendations consider slightly more white tuna and more total seafood each week safe. It should be noted that canned light tuna is lower in mercury than regular tuna, but it is an unreliable source of omega-3 fat. In sum, although foods clearly labeled good or bad may comfort us all, albacore tuna is an example of how a food can be healthful, even though it’s not advisable to eat it daily.

Q: If I do yoga every day, is that enough exercise to keep me healthy?

A: Yoga increases flexibility, improves muscle tone, relieves stress, and helps with certain types of pain management. Depending on the type of yoga, however, it may not offer enough strength-building exercise to maintain your body muscle. Furthermore, fitness experts say that only power yoga, or astanga yoga, provides a good aerobic (“cardio”) workout, which is important for your heart and overall well-being. If your work and daily life activities don’t increase your heart rate a little for an extended period most days, you should add in some regular walking, swimming, biking, or other type of aerobic activities.

How much seafood should I eat to get enough omega-3 fats?

A: Omega-3 fat is a type of polyunsaturated fat that seems to help prevent both heart disease and cancer. You can get the healthy levels most experts recommend with two three-ounce servings of fish per week. If you want to reach the upper levels of the recommended amounts, choose fatty fish that are highest in omega-3 fat, like salmon, herring, sardines, whitefish, rainbow trout, bluefish, sea bass, fresh bluefin tuna, or albacore (white) tuna, either fresh or canned. In addition to fish, or in place of it, you could eat some plant foods that provide a different, but still healthy, form of omega-3 fat. These foods include canola oil, walnuts, walnut oil, flaxseeds, and flaxseed oil.

Q: If someone has tried to lose weight and failed, does it make sense to try again?

A: It’s common for people trying to lose weight to feel haunted by past attempts. But you need to distinguish between what you did in the past to lose weight and what you will do now. If you repeat what you did last time, you’ll probably get the same result. On the other hand, if your weight loss efforts were too restrictive or demanding in the past, and you now try a balanced, flexible approach, you may succeed. Your new mantra and mindset should be: That was then, this is now. However, don’t be afraid to learn from the past. Look at where your efforts were sidetracked before. Use your creativity to come up with new solutions to face previous problem situations. If you suffered through eating tasteless but healthy foods, learn how to make healthier foods taste so good you enjoy them. Instead of totally restricting foods, set reasonable limits and learn portion control. For suggestions on food choices and appropriate amounts of food, check out the American Institute for Cancer Research’s approach to eating called the New American Plate. You can find this information online at www.aicr.org/publications/nap/nap2.lasso. Lastly, to help those excess pounds wither away, make exercise a habit. Regular exercise will also help increase your energy and relieve stress.

 

Q: How nutritious is eggplant?

A: Eggplant’s reputation has changed a lot. Formerly, nutritionists could only say that eggplant is a good source of fiber, since its vitamin and mineral content is small. But now scientists are discovering health-promoting phytochemicals in fruits, vegetables and whole grains, and it’s a whole different story. Eggplant is rich in antioxidant phytochemicals. In fact, the phenols, a class of phytochemicals eggplant contains, are among the most potent scavengers of highly reactive “free radicals” — molecules that can promote cancer development or heart disease. Unfortunately, higher levels of these protective phytochemicals tend to cause a more bitter taste. Researchers are at work creating varieties of eggplant that balance protective phenols with good taste. Meanwhile, choose only fresh eggplant with dark, shiny skin, and use them within a day or two. As eggplants age, they lose their mild flavor and become more bitter. When you cook eggplant, grill, roast, or broil it, rather than fry it. Otherwise, a high fat and high calorie content may outweigh the antioxidant benefits.