Colloidal Oatmeal -- What's the Deal?

I am a big fan of oatmeal baths. Actually, it may be just an extension of my general philosophy of sickness -- just about anything can be treated with tea and a warm bath. Sore throat? Tea, bath. Tummy ache? Tea (peppermint or ginger) and bath. Cramps? Tea, bath. Feeling terrible, depressed, whatever? Tea with plenty of sugar. Bath. Maybe turn off the lights and have bath by candlelight. Ahhhh....

Eczema? Hives? Bath. Tea would be soothing -- it always is -- but not necessary in this case. Although I guess it could help to be more hydrated in the case of eczema.

Anyway, the point is.... little E (my 4 yo) has terrible eczema. Last night she cried. It was awful. Her legs were covered in raised red blotches and she had scratched her belly and legs to the point of drawing blood. So, I went to the store and bought the whole anti-itch spectrum of products.

One of the products that I always rely on is colloidal oatmeal -- E really enjoys an oatmeal bath and it does seem to be very soothing. Just make sure to use lukewarm, NOT HOT, water because hot water just exacerbates skin problems. Normally I buy Aveeno oatmeal, but my supermarket also offered (for 2 dollars less) a large bag of colloidal oatmeal -- considering the number of baths it would work for, it was at least half the price of Aveeno. I looked at the ingredients -- both were 100% colloidal oatmeal, so I opted for the less expensive option.

When I got home, I started to wonder.... what the heck is colloidal oatmeal? Is it just finely ground oatmeal? What's the deal?

The package says not to eat the oatmeal. Colloidaloatmeal.com (no kidding) says the same thing. But the same website gives instructions on making colloidal oatmeal -- basically, you just grind up oats (not an package of instant oatmeal!) to a very fine consistency. A coffee grinder would probably work fine. That would be a HUGE savings.

So why does the package say not to eat it? Is finely ground oatmeal a danger? Or are they using some sub-human grade of oat? Maybe it's just gross? Who knows....

Another advantage of the oatmeal bath is that it's naturally cleansing because of saponins in the oats that attract dirt and oils (source). Little eczema sufferers should not be using soap because it is very harsh and drying, so any cleansing that comes through oatmeal is a nice bonus :)

So.... note for future:
Aveeno oatmeal baths (8 packets) -- 6.99 on Drugstore.com
Giant bag of colloidal oatmeal -- <4.99 at HEB
grind oats -- <1.00/pound

It's awesome when it's less expensive to be green. No trip to the store. No extra packaging. Just grind the oats you already have. Beautiful