I didn't set out to cause offense, my comments were in response...

I didn't set out to cause offense, my comments were in response to the 'nationality' in question being underscored as a mark of authority - the latter is something I'm not found of, whether it originates from Afghanistan, Italy, China or Germany: me no like it.
It has been a boring day, no posts till the arvo, BOT's trading sideways on low volumes...Bfarmer made an attempt to joke about the only posts, I chipped in....no harm intended.
I was expecting more comments on the substance of the 'German' study about the apparently causal relation between dairy intake and acne, but there was none. I guess that there'd have been a similar 'response' if one was to post on NSB 's forum about a casual relation between dairy intake and stroke, or on ACW's forum about a causal relation between dairy intake and Alzheimer's disease.
If one take reader1's advice and "reads beyond the headline and abstract" (some may be offended by what is implied in that advice), one finds some interesting facts about the 'study' and its claims (it is actually a selective review of previous studies).
I found it puzzling, among other things, to learn that "data from molecular biological and epi‐demiological studies thus support the notion that excessive consumption of milk promotes carcinogenesis".
And yet global cancer data does not show a correlate between dairy consumption per capita and cancer rates: Finland has the highest annual per capita consumption in the world at 360L but it lists 30th in for cancer rates in the world, in Israel annual per capita consumption is around 180L and it ranks 50th, Australia average annual consumption is at 105L per capita but we rank 1st...?

https://www.wcrf.org/dietandcancer/cancer-trends/data-cancer-frequency-country
https://www.dairyaustralia.com.au/industry/production-and-sales/consumption-summary
https://www.luke.fi/en/natural-resources/agriculture/milk-production/
https://www.moag.gov.il/yhidotmisrad/research_economy_strategy/publication/2018/Documents/0%20Michal%20EU%20December%20%202017%20publ.pdf

That nutrition and diet are affecting overall health was pointed out by Hippocrates some two and a half millennia ago: " Let food be thy medicine and medicine be thy food ".
Acne too is affected? Who would have thought....
What do dermatologists think of that?
The American Academy of Dermatology/American Academy of Dermatology Association. Guidelines of care for acne vulgaris management:
"(a) dietary restriction (either specific foods or food classes) has not been demonstrated to be of benefit in the treatment of acne and (b) that there are few clinical studies available in the peer-reviewed literature that directly evaluate the effectiveness of dietary restriction or the consumption of specific foods or food groups to improve acne."

https://www.ncbi.nlm.nih.gov/pubmed/17276540

There's much to say about the milk industry negative effect on the environment, and on cows too, but trying to characterize milk per se as a carcinogen agent stinks as a rat to me.