(CNN) -- Yes, go ahead and add yogurt to your healthy foods list if you haven't already. Whether you choose plain, Greek, flavored or low-fat, yogurt is a nutrient-packed snack that nourishes you with a generous amount of calcium and protein, along with B vitamins and minerals, including potassium, phosphorus and magnesium.
A single 8-ounce cup of plain low-fat yogurt delivers more than 400 milligrams of calcium -- that's close to half of your daily needs.
Yogurt is made from milk fermented with the bacteria Lactobacillus bulgaricus and Streptococcus thermophilus. These beneficial bacteria, also known as "probiotics," help preserve yogurt and improve its taste. (Other probiotics are often part of the microbial culture used to make yogurt and are usually listed on the ingredient statement, but L. bulgaricus and S. thermophilus are required).
Probiotics help digest the milk sugar lactose, making yogurt often tolerable by those who can't eat dairy foods. In addition to supporting digestion, research suggests that probiotics in yogurt may boost the functioning of the immune system.
If you want to give your yogurt a nutritional upgrade, go for Greek yogurt, which can pack about double the protein of regular yogurt thanks to its straining process, which removes the liquid whey along with some sugars. For example, a 6-ounce cup of nonfat plain Stonyfield yogurt has 8 grams of protein and 12 grams of sugar. But a slightly smaller size (5.3 ounces) cup of nonfat plain Greek yogurt has 15 grams of protein and 6 grams of sugar. The Greek version also has about half the sodium (60 milligrams vs. 115 milligrams).
Yogurts made from whole milk are higher in saturated fat, though emerging research on dairy fat indicates that it may not negatively affect health. In one study, a higher intake of saturated fat from dairy was associated with a lower risk of cardiovascular disease, but a higher intake of saturated fat from meat was associated with greater risk.
Still, fat contributes calories: A container of fat-free Greek yogurt has 100 calories and zero grams of fat; the whole milk version has 7 grams of saturated fat and 190 calories.
Whatever type of yogurt you choose, steer clear of those with "fruit on the bottom" or other sweeteners, which can double or triple the sugar content, turning your healthful cup of yogurt into a higher-calorie dairy dessert. A 6-ounce cup of plain fat-free Stonyfield has 12 grams of sugar; the same amount of fat-free French vanilla has 25 grams, and a chocolate-flavored cup has 35 grams of sugar -- or almost triple the amount. Add your own fresh berries to yogurt to boost natural sweetness and fiber.
