Hi J.,
Congratulations to you and your family!! As far as introducing cow's milk - yes, it should be whole milk. I would suggest an organic whole milk (WILD OATS) has reasonable prices. When introducing milk, I would recommend using a sipper cup. The serving size for milk is 4-6 oz. Children between 1-3 years of age need 3 servings from the milk group. This could be whole milk, yogurt or cheese. If the boys do not really like milk (some kids are not milk drinkers) - don't worry, they can get calcium from cheese, fortified cereal and vegetables.
As far as transitioning, just substitute one of the formula feedings with whole milk. It does not have to be heated milk - it can be cold. Remember, milk should be given in a sipper cup. Formula can be in the bottle. Also, the boys should be off the bottle by one year - 14 months at the latest.
Hope this helps.
L. Kandell, MS, RD, IBCLC
Registered Dietitian/Pediatric Specialist
International Board Certified Lactation Consultant
AFFILIATED NUTRITION CONSULTANTS, LLC
Scottsdale, AZ 85258
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