Are you as confused about all the advertisements about infant formula as most of my patients? If so, here’s some evidence-based, trustworthy information that will help keep you from getting ripped off by unfounded formula claims and help you provide your child with great nutrition, while saving money.
More Information:
Although the American Academy of Pediatrics (AAP) and the American Academy of Family Physicians (AAFP) recommend breast milk for optimal infant nutrition, many parents still choose formula as an acceptable alternative. The wide variety of available formulas is not only confusing to parents, but also to physicians. So what’s a parent to do?
According to the AAFP, formulas can be classified according to three basic criteria: 
 

• caloric density, 
• carbohydrate source, and 
• protein composition. 

 
You can find a table with all the formulas classified this way here.
When it coms to iron-containing formula, the AAFP and AAP say that all infants should receive iron-fortified formula to prevent iron deficiency anemia. Low-iron formulas are commercially available, and some parents choose these formulas with the belief that iron causes stomach upset – even though there is no proof of this. Therefore, most physicians strongly counsel parents to NOT use low-iron products.
And, to save money, it’s important to know that there is NO compelling evidence upon which to recommend formula that supplements with docosahexaenoic acid (DHA) or arachidonic acid (AA) for term babies.
About AA and DHA supplemented formula, the AAFP says:

Recently, formulas with long-chain polyunsaturated fatty acids have been heavily marketed to promote eye and brain development. Arachidonic acid (AA) and docosahexaenoic acid (DHA) are the most common additives. 

These fatty acids are found in breast milk, but not conventional formula, and are thought to be important in the development of membrane constituents in the central nervous system. 

Clinical trials of the effects of AA and DHA on cognitive, social, and motor development have been (performed). Although no harm has been demonstrated, most well-conducted randomized trials show no benefit. 

Thus, recent Cochrane reviews conclude that supplementation of formula with DHA and AA cannot be recommended based on current evidence. Additionally, these formulas cost more than formulas without the above additives.

Soy formulas are indicated for congenital lactase deficiency and galactosemia, but are not recommended for colic because of insufficient evidence of benefit. 
Hypoallergenic formulas with extensively hydrolyzed protein are effective for the treatment of milk protein allergy and the prevention of atopic disease in high-risk infants — but seem to offer no benefit over the less expensive infant formulas. 
Antireflux formulas decrease spitting and regurgitation, but have not been shown to affect growth or development. The good news is that most infants with reflux require no treatment and do just as well with the routine and less expensive formulas.
Concerning toddler or “next step” formulas that are being heavily marketed for children nine to 24 months of age, the AAFP says this:

These milk-based formulas contain added iron, vitamin C, vitamin E, and zinc. They also contain DHA and AA and more calcium than standard infant formulas (but not significantly more than whole milk).

Manufacturers’ information describes toddler formula as “insurance” or “extra nutrition” for picky toddlers who may not eat a well-balanced diet of solids. 

There is no evidence of advantage over whole milk in terms of growth or development.

Because toddler formulas are significantly more expensive than whole milk, family physicians can counsel parents against routine use. Parents who remain concerned about picky eaters could be directed toward a multivitamin instead of these more expensive formulas.
For more detailed information on these and other recommendations about infant formula, there’s a great article, written for family physicians who are counseling parents about infant formula. This article will help you, as a parent, counter consumer advertising that is not evidence-based. You can find the article here.