Lactose question

[Bru]

There are various people who claim to be "lactose intolerant" - they avoid milk / dairy and find that the lactose gives them a bad reaction.
Is the lactose in dairy the same lactose added when brewing ?
Does it give those who are lactose intolerant a bad reaction ?

 

[Poindexter]

Only one way to be sure about the diarrhea thing, but yes, lactose is lactose.

 

[david_42]

Lactose is a simple sugar, so anything that says lactose is the same chemical. Lactose tolerance in adults is relatively recent mutation, probably less than 7000 years old.

 

[Bru]

Ive heard a theory that the "intolerance" is actually related to the type of protein found in milk and not the lactose. Ive never heard of anyone "reacting" (swine flue type reaction ) after drinking a stout containing lactose.

 

[Bru]

On a more serious note - my understanding is that lactose is unfermentable by the yeast and therefore adds sweetness to the finished product without increasing ABV (please correct me if Im wrong) - some recipes add sugar, especially the darker beers (brown sugar) -
When does one add sugar and when does one add lactose ?

 

[SumnerH]

Ive heard a theory that the "intolerance" is actually related to the type of protein found in milk and not the lactose.

Lactose intolerance is medically well-understood, and it's related to the lactose itself. The digestive tract of lactose intolerant people has low (or no) levels of lactase, the enzyme that breaks down lactose into galactose and glucose (both of which are fermentable).

It's usually not all-or-nothing, so small amounts of lactose are often okay even in people who consider themselves lactose intolerance.