I've put a lot of research into baby food lately, and so I wanted to post about it here. Hopefully, it will be of use to someone who has an infant or will have one at some point.
The main issue is what "complementary foods" to give an infant. My initial gut feeling was that proper baby food should be much like proper adult food: fruits, vegetables, and meat. In comparison, you have pediatricians recommending rice cereal as a starter food. This seemed a little strange to me, and so I wanted to really research it to find out what's best.
There has actually been a good amount of research done on this subject. Researchers have found that when manufactured baby foods are used in comparison to just that of traditional foods alone, the only benefits are in terms of Vitamin A and iron. In other words, the combination of fruits, vegetables, and meats can sometimes come up short on these two key nutrients.
But infants ate only traditional foods throughout millions of years of evolution, and apparently got enough of these nutrients then. This seemed puzzling to me, but then I dug a little deeper and found that many traditional societies gave children not just meat, but organ meats as well. And it seems likely that these other types of meat provided these key nutrients. Liver is a prime example. It is very high in iron and also Vitamin A.
In fact, researchers are now starting to believe that meat in general is an ideal first food. The old logic of introducing vegetables, then fruits, then meat doesn't appear to have any scientific basis. Meat is a healthy first food that provides an infant with both iron and zinc, which are essential nutrients for growth.
Once an infant hits six months or so, their internal iron stores run low and they become much more dependent on food sources of iron. To make sure a baby is getting this iron, a parent should come up with a strategy to do this. The iron content in commercially prepared baby meat is fairly low, so a parent would have to feed a child lots of meat to make sure they are getting enough iron. Alternatively, a parent could use a traditional high-iron food like liver, or if they choose, iron-fortified rice cereal.
In terms of Vitamin A, an infant's need can be met by a food like liver, or by choosing the right vegetables. Sweet potatoes are high in Vitamin A (actually a precursor to Vitamin A) and have been shown in studies to improve Vitamin A status.