Question: What is a "phytonutrient"?
Answer: Phyto- is derived from the Greek word phyton or phyein, meaning "to bring forth." We usually interpret this term to mean "plant." Thus, a phytonutrient can be thought of as a "plant nutrient," or a nutrient that comes from plants.
The term phytonutrient can be used interchangeably with the term phytochemical, and both words describe plant compounds that are thought to have health benefits. Examples of phytonutrients include isoflavones - found in soy products, flavonoids in blueberries, carotenoids in carrots and lycopene in tomatoes.
Phytonutrients have received a lot of media attention in the last several years as researchers continue to study the possible disease-fighting benefits of these compounds. But the evidence is still emerging and there's no consensus yet on how much of each type of phytonutrient you actually need - or what amounts seem to offer the most benefit.
The best way to ensure you get plenty of these beneficial nutrients is to eat a wide variety of colorful fruits and vegetables.
Q: I've been seeing edamame in all kinds of foods lately, and in the dining halls, too. What is it?
A: Edamame (pronounced ed-ah-MAH-may) are fresh, green soybeans harvested at about 80 percent maturity. If you enjoy Japanese food or frequent sushi restaurants, you are probably familiar with edamame as it is prepared in the pod - usually steamed and salted.
This relatively sweet, buttery bean is a good source of fiber, calcium and potassium, as well as high-quality protein and plant compounds called isoflavones. Emerging evidence suggests that isoflavones may have potential cholesterol-lowering properties and protective benefits against breast and prostate cancers.
One half-cup of steamed or boiled edamame contains about 130 calories, six grams of total fat, 11 grams of protein and four grams of fiber.
Remember, because edamame is a plant food, it contains no cholesterol, and virtually no saturated fat; the fat that is found in the bean is mostly polyunsaturated fat. Add edamame to salads, couscous or rice recipes, or just eat it plain for a healthy snack.
Q: I keep reading about celebrities who say they eat five to six small meals a day - instead of three - to stay thin or lose weight. Does this really work? Or is it just the usual celebrity hype?
A: It depends on your usual eating habits, your schedule and what works best for you. The caveat to eating five-to-six meals per day is that the meals contain fewer calories than a typical "three-squares-a-day" plan.
If, for example, your daily goal is 2,000 calories, you could eat five smaller 400-calorie meals, or three somewhat larger 600-calorie meals, with 200 calories to spare for snacks.
I use the terms "smaller" and "larger" loosely. A "small" meal of a donut and coffee isn't going to provide you with many nutrients (mostly just calories and fat), while a "large" meal does not give license to pile on the food. In fact, a "small" meal may even be bigger in portion size than a "large" meal - for example, a large salad with lots of vegetables and relatively few add-ons.
The terms "small" and "large" have to do with caloric content of the meals. The key here is to balance the calories you eat throughout the day. Many people eat five-to-six smaller meals per day because it keeps them from feeling hungry and overindulging.
For others, however, eating so frequently may actually cause them to eat too many calories over the course of the day. You have to figure out what works best for you, your schedule, and your lifestyle.
The bottom line is that eating excess calories - whether you eat five or six small meals a day or three square meals a day - will lead to weight gain. Remember, it's not about how many meals a day you eat; it's about how many calories you eat.
Sara Wilson is a registered dietitian and a graduate student in Nutrition Communication at the Friedman School of Nutrition Science and Policy. She has a BS in Nutrition from Syracuse University, and worked as a clinical dietitian prior to coming to Tufts. Wilson is also co-editor of Balance.
