Milk allergies are a complicated thing filled with a lot of gross misunderstanding. A lot of people think they have issues with lactose, then avoid cheese (which contains almost no lactose if even a mildly mature cheese).
While some people do have issues with lactose, there's really three components to dairy that one can have issues with.
- Protein: Casein
- Carbohydrate: Lactose
- Fat: Cream (not sure what else to call it)
I thought I was lactose intolerant for the longest time. I had lactaid products or would take lactase (lactose digesting enzyme) with meals and didn't notice any improvement.
Now I'm not a doctor, nutritionist, etc. I read Wikipedia's article on A2 milk and was upset finding it basically regarded as a pseudoscience. I know for a fact that is not the case.
Casein comes in two types, A1-protein and A2-protein. Your typical milk monster Holstein cows produce milk that contains A1 and A2 protein. Just about every other milk producing animal only produces A2 milk. Jersey cows usually produce only A2 protein, but I think some also produce A1.
I absolutely love dairy and it's taken me a while to figure out what I can and can't have. I hate seeing people avoiding all of it on misinformation without good testing to know they really can't have any of it.
I think some people avoid dairy because it's fashionable to avoid. Or they think some obscure issue is caused by it. I will tell you what a real dairy issue is like. It's like having the flu bit milder. It feels terrible. I've felt like I had to throw up and my only chance to improve was having a hot bath (which works well for me whenever I'm sick). If you aren't feeling like that, you could be fine or something mild is going on. But if you have a severe issue with dairy, you know it when you have it.
I can have basically unlimited cheese, butter, or goat's milk/cheese/what have you. What gets me in trouble is cow's milk, yogurt, and icecream.
Why cheese doesn't affect me, I don't know. I am thinking the protein is broken down somehow in the cheesemaking process. You would think the yogurt making process would also work, but it doesn't (or at least not reliably). So then you can say: "Ah, it's lactose!" but it's not.
I can drink tall glasses of whole A2 milk (this company produces milk which comes from A1-protein free cows) with no issues. A cup of yogurt with A1 protein has me feeling pretty bad. So this is astonishing.
Obviously, I have some kind of issue digesting A1 milk protein. And not everyone does. But for all of the people saying it's some kind of fad, etc, there is merit to it. I would be a reliable guinea pig to tell one from the other. Now maybe it doesn't matter for most people, but if you have an issue with A1 protein you should try A2 milk and such.
It doesn't matter for butter, there's so little protein there you'd have to have a really severe issue to notice it. But yogurt, icecream, and plain old milk can cause issues in my experience.
I wasn't always this way, it got worse as I went into my middle twenties. I used to eat a pint of icecream for breakfast without issue.
I know this is kind of a stupid post, devoid of philosophy or new ideas, but if you happen to have issues with dairy and haven't considerd A1 protein issues, it could well be worth doing.