This dairy option comes in a variety of densities. They all contain the same nutrients and vitamins. All cow’s milk is rich in calcium, vitamin D, potassium, and protein. The main differences are calorie and fat content and flavor. Skim milk is only 90 calories per cup, making it a great option for those watching their weight. Gradually increasing in caloric content, 1-2% milks get slightly richer in flavor. And whole milk can contain anywhere from 125-156 calories per cup, but it’s rich and creamy and great for babies and toddlers, who require more fat for their developing brains.