Milk separates into curds and whey (Little Miss Muffet!) The curds are cottage cheese; whey is the watery fluid you often see in it. Curds are made into yogurt and cheese. Most of the lactose stays in the whey; so yogurt, cheese and cottage cheese are very low in lactose while staying high in calcium and protein (and fat!). I'll give my little guys yogurt at least twice a week, sometimes three or occasionally four times. (They love strawberry, blackberry-pomegranate, and key lime pie.) I'll give them a few shreds of cheddar or colby cheese maybe once a month at most. They won't eat cottage cheese whatever kind I get, or however I fix it.