Breastfeeding is indeed the best course. Breast milk provides all of an infant's nutritional needs in terms of macronutrients, vitamins and minerals; it also confers antibodies that can help protect against many infectious diseases. Breast-fed babies may also have a lower risk of allergies, asthma and obesity as they mature than babies who are fed formula.
Breastfeeding helps mothers as well. Nursing releases oxytocin, a hormone that can help the uterus return to normal size after delivery. It can also help a mother lose extra weight gained during pregnancy and facilitates the mother-baby bonding process. Later in life, women who breast-fed appear to be less likely to contract breast or ovarian cancer.
However, for many women, it is simply impossible to be with their infants 24 hours a day, seven days a week. Even the most conscientious and dedicated mother in the modern world is sometimes required by circumstances to feed her baby from a bottle (or have someone else do the bottle-feeding).
The first rule of bottle-feeding is that giving the baby expressed human milk is vastly superior to feeding with formula. Infant formulas are much improved in recent years, but none can match the perfect mix of nutrients that breast milk provides.
Aside from that, it is vital to use a bottle that is free of bisphenol A, commonly known as BPA, and estrogenic activity. This chemical, added to many plastics, can leach into food and has been linked to possible effects on the brain and prostate development in young children. I also recommend using a bottle that vents efficiently, to avoid the risk of colic and spit-up. Finally, if there is a problem, a bottle that is produced entirely in the U.S. provides complete lot-number traceability, an important aspect of quality assurance.
For these reasons, I recently worked in conjunction with the Key Baby company to develop a line of bottles, sippy cups and pacifiers, and a breast-pump will be added to the line in 2010. As with all products under the Weil brand, all my profits from royalties from sales of Weil Baby products are donated directly to the Weil Foundation, a not-for-profit organization dedicated to supporting integrative medicine through education, training and research.) This line meets or exceeds all of my criteria, and provides a next-best experience to breastfeeding. I highly recommend it.
Andrew Weil, M.D.