Just to follow-up on what Don said.

1. LI symptoms come from the inability to digest lactose. True milk protein
allergy symptoms are usually quite different, but protein hypersensitivity
can create very similar symptoms. It can be hard to distinguish between the
two without testing.

2. You can take more than 2 Ultra Lactaids. If they don't work, you might
try a different brand: Lactaid doesn't appear to work for everyone, for no
known reasons. Or it could mean that you have the protein hypersensitivity
instead. Or something else entirely.

3. I believe that commercial milk fat is water free, while butter is 20%
water and up to 1% lactose. Don is right, many margarines contain whey,
which is almost pure lactose, but even so the total lactose amount should
still be small.

4. Drinking regular amounts of milk reduces symptoms for some people by
changing the bacteria in your colon away from those that ferment lactose to
those that digest it. It doesn't always work, and if it does the first
couple of weeks can be distressing.

5. LI symptoms are unpredictable because the amount of lactose in food is
unpredictable and the way that the food buffers the timing of the lactose
entering the intestines is unpredictable. But cooking has no impact on
lactose at all.

You can find answers to these and many more questions about LI on my web
site.

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