I mentioned this already, but it's buried in that big mass of typing. Some, us, people have overactive sebaceous glands which enable the liver to purge toxins through the skin. But once puberty is over many peoples' glands dry up and they are unable to get acne, or use that as a form of toxin purging anymore.
"unable to get acne" so in some cases, a case of acne is not necessarily the sign of a person who is worse off health wise. His clear skinned friend could be just as bad, but the damage is staying on his inside.
but then why dont they have acne in non western countries? their livers would still be burdened by numerous things, like less than clean water, vitamin defencies, etc and some of those people must have overactive sebaceous glands. so why don't they get acne?
Because acne is inflammatory. A big reason why we (probably.. hehe

) get acne is because of the well-documented omega 3: omega 6 ratios westerners have in comparison to non western countries. Many Americans get to the point of having a 1:60 omega 3:omega 6 ratio, usually because of high vegetable oil content in their foods. Non-western countries usually have simpler diets that are highly carb-focused with little fat. This little amount of fat will both keep their insulin sensitivity high (good thing) and the ratio of omega 3:6s that they get will be more around the optimal range of 1:3, 1:2, or 1:1.
All of this coincides with what Zmffy has said, but he places a large emphasis on liver health as well. Like he said in his post, his friend told him that while eating properly (and with a good omega 3:6 ratio) will stop further damage to the liver, but wouldn't heal the damage he's already done. This is why he then suggests adding liver cleansers and fasts, which help give the liver time to repair.
Personally I don't agree with Zmffy's theory that the most fundamental cause of acne begins with liver damage, it probably just has a fair bit to do with the entire process. Whether or not acne is completely inflammatory based or whether it is the liver's backup system is irrelevant, we CAN'T know so we must only study probabilities --
We've tested and found that a higher amount of omega 3 EFAs in your body has an anti-inflammatory effect, and a high amount of omega 6 EFAs in your body correlates with a higher degree of inflammation. We've also found that when we eat a large amount of fatty foods, our blood fat levels increase and promote a lower degree of insulin sensitivity. This means that when we go and eat sugary foods, our body needs to pump out more insulin than usual to deliver the same amount of sugar to the same cells. It also means that our blood sugar stays higher for longer periods of time, which is dangerous, and promotes candida growth (which is a fungal backup system that saves your life, but also has various hormonal effects on your body which promote acne)... and diabetes. Point is: eating too many omega 6 EFAs is disastrous and highly inflammatory. Non-western countries don't eat a lot of Omega 6s (OR 3s, obviously, since they don't eat much fat in general, but their food sources like fish, flax, fruits, whole grain rice, whatever, they have better omega 3:6 ratios).
Liver damage, I assume, would promote a higher degree of inflammation in your body via D6D inhibition (delta 6 desaturase, which catalyzes alpha-linolenic acid(ALA) into eicosapentaenoic acid (EPA), which then goes through various conversions into the 1st prostaglandin... aaah I suggest you go look it up, there's a lot to learn

) and D5D promotion, which would be disastrous for acne-prone individuals. In my opinion, acne is definitely not caused by one specific thing -- your body works together and some people have more damage in acne-causing areas than others, so some fixes and medications will work on Billy, who has a shot liver, but not on Sally, who has Leaky Gut Syndrome.
... Yep.