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Updated April 22, 2014.

One of the biggest questions parents of younger babies have regards when to start baby food. Some parents will hotly debate when is the "best" time to start solids. Maybe you have lent an ear to some strong opinions on the matter (start whenever you like, wait until 4 months, wait until 6 months, etc), and perhaps those discussion have left you confused, frustrated, or simply annoyed. Let's take a look at what the research really says about the start of baby food.

The American Academy of Pediatrics Position on When to Start Solids

The fact is that the American Academy of Pediatrics (AAP) advocates waiting until at least 4 to 6 months to start solids, and with good reason. Many medical studies confirm this timeline, including a February 2011 publication in Pediatrics which specifically investigated the timing of solids and the risk of childhood obesity.

Starting Solids Early May Increase Obesity Risk in Formula Fed Infants

The most recent study took a close look at how the timing of solids may affect the rates of obesity in pre-school aged children. What this study found was that, "Among infants who were never breastfed or those who stopped breastfeeding before the age of 4 months, the introduction of solids before the age of 4 months was associated with a sixfold increase in the odds of obesity at the age of 3 years." (Pediatrics 2011).

In the past, some have argued that formula-fed infants experience "rapid early growth", meaning that formula fed infants tend to gain weight more quickly in the beginning than breastfed babies.

This study found that rapid early growth did not explain the increased risk of obesity in preschool age children.

Timing of Solids, Obesity, and Breastfed Infants

Interestingly, the researchers did not make the same conclusions when it came to babies who were breastfed. Instead, they found that there was little difference in the rates of obesity in infants who started solids before 4 months of age, those who started between 4-5 months of age, and those at or after 6 months. It seems the rates of obesity in these breastfed babies were quite similar.

So does that mean that breastfeeding moms should feel confident that they can start solids as soon as they want? Not exactly. You have to keep in mind that this study was considering only one health risk - obesity. However, past studies have considered that starting solids before age 4 months may have other health risks. Additionally, because young babies lack adequate head control and still may show evidence of a reflex known as "tongue reflex", babies younger than 4 months are more apt to choke, even on thin baby food purées and runny infant cereal. Regardless of the fact that there was no substantial difference in timing of solids in breastfed infants and the risk of preschool obesity, the study still urged parents to keep with the AAP's suggested timing of the start of solids between 4 to 6 months of age.

Use These Practical Tips When You Start Baby Food

So after all that medical talk, perhaps you are wondering what are the practical take-aways about starting solids. Recently, we've learned quite a bit about the how/when/what of starting solids which actually de-bunks a lot of popular opinion through medical research. Here are some helpful insights on starting solids.

• Should I Delay Certain Foods to Prevent Allergies?
• Should I Time Certain Foods at a Specific Age?
• How Do I Begin Infant Cereal?
• Can I Start With Fruits and Veggies?
• When Can My Baby Have Juice?
• What are Some Tips for the Start of Baby Food?

More info: Should I Worry about Nitrates and Homemade Baby Food

<sub>Sources:

Susanna Y. Huh, MD, MPH, Sheryl L. Rifas-Shiman, MPH, Elsie M. Taveras, MD, MPH, Emily Oken, MD, MPH, and Matthew W. Gillman, MD, SM. Timing of Solid Food Introduction and Risk of Obesity in Preschool-Aged ChildrenPediatrics February 2011.

Andrea C Wilson, J Stewart Forsyth, Stephen A Greene, Linda Irvine, Catherine Hau, Peter W Howie. Relation of infant diet to childhood health: seven year follow up of cohort of children in Dundee infant feeding study. BMJ 1998; 316 : 21</sub>