What is Milk Soy Protein Intolerance?

A milk soy protein intolerance (MSPI) is an intolerance to the proteins found in milk and soy. Obvious, right?

Anywhere from 1%-10% of children will be diagnosed with MSPI, but it’s believed that about 90% of children diagnosed with MSPI will grow out of it by age three. 

While there is a lot most doctors still don’t understand about MSPI, it is a very real condition with devastating consequences to your child’s health if it is not recognized and addressed properly. Sadly, it’s common not to receive a diagnosis until your baby is about four months old.

How is MSPI Diagnosed?

One of the telltale signs of MSPI is the timing in which it appears. Breastfed and formula-fed babies alike will show symptoms at about three weeks of age. Unfortunately, there is currently no test that detects MSPI. Common symptoms include, but are not limited to:

• Inconsolable crying, which may be temporarily helped by soothing methods but will start up again shortly after. 
• Runny stool with mucus and/or blood (occult or visible). 
• Spitting up a lot and/or vomiting. 
• Refusing to eat even though they should be hungry or, in my baby’s case, hungry all the time. An intolerance to foods we consume causes inflammation of our insides. Because of this, some babies may refuse to eat or be hungry all the time due to frequent diarrhea and spitting up. 
• Some babies may not be able to gain weight or (even more worrisome) could start losing weight. 
• Skin rashes/eczema. 

So, what’s the cure? Eliminate the offending proteins from your baby’s diet. Breastfeeding moms must eliminate all milk, soy, and usually eggs from their diet. 

A gastroenterologist told me that she believed eggs to be a whole separate problem, but I wonder if the research on that is solid yet. The reason is that in my area, most chickens eat soy feed, and I firmly believe that eggs were a problem for my baby because of this. When her soy intolerance subsided, so did her problems with eggs.

Formula Options for Babies with MSPI

The majority of store-brand formula is made from cow’s milk proteins, and while you can buy special, more gentle formula called Alimentum, it still contains cow’s milk protein AND soy. It is recommended for babies with mild to moderate MSPI.

Your next best option is a formula called Nutramigen. While it does contain soy oil, it does not contain soy protein.

Both have a taste that would take some getting used to, but feeding your baby is the most important thing, and if you have to mix tolerable formula with what they’re used to for taste, then by all means, do it.

Try your best to ween your baby to a diet free of foods they can’t tolerate as quickly as possible. 

Unfortunately, because trace amounts of the intolerable proteins remain in our systems for some time, it usually takes about three weeks for symptoms to improve drastically. Still, if MSPI is your culprit, then you’ll often see a difference in your baby’s level of discomfort within 48 hours.