- Babies gain weight at very different rates. Some babies will double their birth weight by the time they're three or four months of age, other babies gain much more slowly, some gain much more quickly. If a baby is doing well, if mom's milk is in and the baby is urinating a lot and pooping a lot and smiling at seven weeks of age and moving very nicely, I don't really think that you need to worry about weight gain. One of the things that we discuss in my office is that we really can't ever remember seeing a baby who had slow weight gain as the only marker of a serious problem. In other words, a baby gaining weight slowly and not meeting milestones, or a baby who is gaining weight slowly and who isn't eager to breastfeed, or who isn't urinating, or whose respiratory pattern is off, that baby deserves a lot of extra scrutiny. But a baby who's growing and thriving is allowed to gain weight slowly, and very, very rarely should that baby get supplemental formula.

- The human infant doesn't grow quite as fast as they do in the first 12 months ever again in their lifetime. From birth to about three months, the average weight gain is between one half to one ounce a day. From three months to six months, it drops to just a half ounce a day, and from six months to the end of the first year, it drops to between four to five tenths of an ounce per day. Correspondingly, the human infant is also growing in height during that period, and they average in the first six months approximately one inch per month, and in the second six months, a half inch per month.

- I'm always amazed at the number of parents who worry that their children are too lean. Healthy children, children offered really good food, sometimes children with both parents tall and lean, and the parents and the grandparents and the aunts and uncles are worried that the child is too lean. And what I tell them is that it's a rare American who makes a New Year's resolution to gain 10 pounds. I know I said it last year, boy, this year I'm gonna try to gain 10 pounds. Everybody is trying to get leaner and fitter. Children are really good animals. They get all the calories they need, offer them good food, they will eat good food. There are children with illnesses. They are much more obviously unwell than just a lean, healthy child. The kids who I see, virtually every child, and I feel like saying every child, who I see in my office who is quite lean is also just bouncing off the walls, running in circles in the exam room, playing with every single toy, and they're lean. And what I point out to the parents is that if they turn on the television and they watch the Olympics or the NBA, they'll see that the best athletes do not have a lot of extra fat, and kids are natural athletes until we get in their way. If your child is lean and healthy and active, leave him alone.