Q. Are all nuts healthy, or are some more nutritious than others?

A. The special nutrient contributions of each type of nut vary, but all are healthy if you keep portion sizes small so your calorie consumption stays on target for a healthy weight.

Studies with a variety of nuts show that when people substitute nuts for foods such as fatty meat and deep-fried foods high in saturated or trans fats, blood cholesterol usually declines. Almonds, walnuts, peanuts, pistachios, pine nuts and pecans all have 3 grams or less of cholesterol-raising saturated fat in a one-and-a-half ounce serving (about one-third cup). Nuts contain mostly monounsaturated fat; walnuts are high in polyunsaturated fat, some of which is an omega-3 fat that's in the same family with the heart-healthy fat found in salmon and other fatty fish.

Cashews and almonds are especially high in magnesium, pecans are loaded with manganese and pistachios are rich in vitamin B-6. Brazil nuts are an outstanding source of the antioxidant mineral selenium. Almonds are exceptional sources of vitamin E, another antioxidant; hazelnuts, peanuts and Brazil nuts are also good sources.

All nuts provide varying combinations of natural antioxidants, cholesterol-lowering phytosterols, and dietary fiber and serve as a protein source, too. Since they all contain 240 to 285 calories per one-third cup, make sure that you don't just add nuts to your diet, but substitute them for less-healthy foods.

Q. Are drinks made with matcha green tea added as super-healthy as they sound?

A. Matcha is simply ground green tea leaves. As traditionally prepared in Japan, a small amount of these ground leaves were whisked with plain hot water to produce tea. Both in Japan and the United States, it is now a common ingredient in sweets (where it adds a green color to ice cream, pudding and candy) and sweetened milk drinks such as lattes, smoothies and milkshakes.

Matcha is an expensive form of tea, although price and quality vary with where it was grown, timing and method of harvest, and the measures taken to keep the leaves from oxidizing. Research is limited on how its health benefits compare to regular green tea. One study from the University of Colorado found that matcha tea contained much, much higher antioxidants than green tea. However this comparison involved high quality matcha and relatively low quality green tea. USDA data on green tea suggests that its content may not be much different from that of matcha.

While smoothies and lattes are a popular way to get green tea antioxidants, most of these drinks contain enough added sugar that they're far from low-calorie. For example, compared to 100 calories in the same size coffee latte, a 12-ounce matcha green tea latte made with skim milk from one popular national coffee bar chain contains 210 calories and includes more than six teaspoons of added sugar.

Q. Are lentils as nutritious as dried beans (such as kidney beans, black beans and garbanzo beans)?

A. Absolutely! Like all dried beans and peas, lentils are high in fiber. Just a half-cup of cooked lentils provides nearly as much fiber as two cups of cooked oatmeal, and much of it is soluble fiber that helps lower blood cholesterol. All legumes are excellent sources of iron and the B vitamin folate that is so important to producing and maintaining healthy DNA, and lentils are highest of all.

Like other legumes, lentils provide both protein and antioxidant phytochemicals like flavonoids. Limited data suggests that whole lentils that are not split and skinned may retain the most antioxidant power.

Lentils' easy preparation requires no soaking like other dried beans, so you can go from pantry to table in about half an hour, depending on the type of lentil you choose. Red lentils take less time to cook and become puree-like, so they're great for thickening soups or in dal. Green and brown lentils hold their shape so you can use them in salads, soups or entrees.

• Provided by the American Institute for Cancer Research. Learn more at aicr.org.