It appalls me that doctors recommend, or support the consumption of any type of cereal, or grains in infancy. Babies simply cannot digest these foods until they are around 18 mos old. Early introduction of food, particularly grains, in infancy can lead to leaky gut, which then manifests itself into a slew of other problems like asthma, allergies, weakened immune system, inability to absorb nutrients, and extra weight gain. Many babies who are fed solids at an early age cannot digest the food, so it is simply stored as fat. Before trusting a doctor, it's best to do quality research before introducing solids. My children did not eat solids until they were one. They were strictly breastfed. They did not wake at night hungry. My first child woke at night b/c mommy didn't have her on a sleep routine at the time- Live and learn! If children are allowed the opportunity to truly feed themselves solid food when they are ready (not pureed, jarred baby food), they learn how to eat properly. They take time to chew their food and eat when they are hungry.
This is a great article from Sarah, The Healthy Home Economist:
http://www.thehealthyhomeeconomist.com/right-way-to-feed-babies/