Hilda Nic Chárthaigh writes:

>Whey is OK for my son, but I take it is NOT for LI?

Commercial whey is only partly whey protein but is predominantly lactose -- 
almost always 50% or more in its dry form which is about the only way it's 
ever used. So whey is the worst ingredient for someone with LI to encounter, 
except for lactose itself.

>What's the story on casein? Is there lactose in casein too?

Yes and no, but mostly no. You will often find casein in one of its many 
forms (usually sodium caseinate) on ingredient lists of foods that claim to 
be lactose-free. Whether this is true is a matter of how good the processing 
is. It appears that, in recent years, processing has improved considerably so 
that if casein is the only milk-based ingredient virtually everyone with LI 
can have it.

> What do LI sufferers do when they want a cup of coffee out and they only 
thing on offer is half and half?

If having it black isn't an option, then why not try a lactase pill? These 
work almost always for almost everybody, although you may need to experiment 
with brands and dosages to find what works best for you. You might want to 
look at my Lactase page in the LI Basics section of my web site.

Steve Carper
Steve Carper's Lactose Intolerance Clearinghouse
http://ourworld.compuserve.com/homepages/stevecarper