Why does lactase enzyme give me diarrhea?

[Entre411]

Does anyone know why lactase enzyme gives me diarrhea and some cramping even though everywhere on the internet says there is no side effects? Or has this happened to you? Back story: About a year ago I started drinking A2 milk to help regulate my period. I never have problems with it and it has helped me so I love drinking it even though it’s more expensive. But in general I’ve always had stomach problems (to the point where once a year, these last 3 years, I’ve had an episode so bad that I’d pass out from the pain and then sweating profusely while going number 2) So a couple weeks ago I decided to try the FODMAP diet. I was avoiding all dairy except the a2 milk already. So I followed everything to a T(I think beans, broccoli and onion were the main culprits for me), except I still drank the A2 to just finish the carton. During that time I felt so great like a different person! No stomach problems at all, perfect movements and a lot of energy. So thinking that lactose free milk will make me feel even better(according to FODMAP diet), I got some lactose free milk to drink. Well went to bed a little gassy and then woke up in the morning with cramps and diarrhea right away. Next day same thing. At first I thought maybe I’m increasing my fiber too fast but by the third try I knew it was the milk. So I ordered the lactase enzyme to put into my a2 milk. Diarrhea went away while waiting a few days for the mail. So I put the enzyme in my A2 milk and I got the same exact symptoms as before! This makes no sense- A2 milk gives me no problems and I feel great drinking it, but lactose free A2 milk tears my stomach up? So I’m obviously having a reaction to just the enzyme. Could anyone shine a light on this or have a similar experience?

[Kentaro]

Does it really matter?

You are not lactose intolerant so you can live without it.

[Stuart24]

The lactase enzyme splits lactose into glucose and galactose. You can easily absorb the glucose, but I'm not sure about the galactose, particularly as "galactans" - things which lead to galactose are FODMAP's. So, the galactose is feeding your bad gut bacteria before you can absorb it. I am equally bad on lactose free milk, and I believe it is for this reason. I find the best milk substitute to be Almond milk. Soya will make you bad, as it is made from the whole bean.

[Entre411 in reply to Stuart24]

Thank you so much for that explanation! Makes a lot of sense to me. Seems like we are meant to break down lactose in our small intestine. I’ve always been sensitive to substances - I can barely take modern medicine. Thanks, I’ll try almond milk and compare to the A2.

[BabsyWabsy in reply to Entre411]

The A2 milk is missing the A1 protein which upsets some people. It comes from cows bred to not secrete the A1 protein. It is very likely the lactose free milk that gave you an issue is made using standard milk containing the A1 protein. On the outside looking in, I would suggest it is the A1 protein rather than lactase enzyme that is giving you a problem.