Updated: Sep 27, 2019
If there's one thing scientists agree on, its that acne is a complex thing. The reasons why a particular person has acne at any one particular time in any one particular place on their skin can be caused by many things or, just to make it even more complex, often a combination of those things. It has nothing to do with face mapping (sorry for those that follow face mapping, acne is just way to complex to be as simple as spots on your chin means your hormones are out of wack and forehead spots mean you have a poor diet) and is often a combination of what is going on inside you and what is going on around you.
Scientists like to simplify things and we're no exception. We explain how acne forms through our "acne forming chain" and, although this is a simplification of what's going on, by understanding the chain we get an insight why some products help some people and why some products don't. We also get to understand why treating acne holistically (as in the whole body) is the best route to reducing its severity and hopefully overcoming it altogether.
So what is the acne forming chain. Simply - its this:
An easy way to think about this chain is to think of each part as a domino. The causes of acne are at the start and the mechanism of acne is towards the end and, critically, knocking over any one domino anywhere on the chain results in acne.
Acne is a chain of events principally driven by hormones & inflammation (although what your skin is exposed to can also play a part, especially if you have a weak skin barrier, but more on that later). The hormones chiefly at work are androgens - these cause the skins sebaceous glands to enlarge and produce sebum (skin oil) and control how our skin shreds. Often, these hormones are at there strongest during preteen years but also can peak from hormonal fluctuation during the menstrual cycle and pregnancy. Our hormones are regulated by who we are (our genetics) and to a lesser extent what we do (our lifestyle). A study of 458 pairs of identical twins and 1099 pairs of fraternal twins found that genes explained 81% of the difference in acne prevalence, while only 19% was explained by lifestyle factors such as diet and stress. While science hasn't yet identified an "acne gene", specific gene mutations can result in excess androgen production and also enlarged sebaceous glands that can cause this domino effect on the rest of the acne forming chain. Our genes also affect later parts of the chain too - genetics also can control how our skin shreds (acne prone skin sheds in sheets rather than pieces and so is more prone to forming a pore clogging plug), how our sebum is made up (acne prone people can have a different 'quality' of sebum) and how our immune system responds (why some people get just a black head to a blocked pore, while others to get angry inflamed nodules). In fact, there is an increasing body of evidence that people with acne may suffer from a continuous low level chronic inflammation as a base line.
Acne is likely hereditary, one study demonstrated that having a first degree relative with acne increased the risk of having acne by four times. However having a predisposition to acne doesn't mean you will have acne - genetics is only one of the domino's in the acne forming chain - but it is more likely. Unfortunately you can't choose the cards life deals you, but you can choose how they are played and by understanding how the chain works it is possible to reduce acne severity or even prevent it altogether. However, for some the genetic domino will always be toppling and so constant attention to the rest of the chain is required to prevent their skin cascading into full blown break outs.
Even for those who don't have a genetic disposition to acne, certain lifestyles and/or the environment they are in can also trigger acne flare ups. In particular diet, stress, the climate (sun, heat and humidity), pollution and what we put on our skin, can all lead to the dominos crashing down and our skin exploding with acne. We will look at each of these triggers and what you can do to stop the dominoes topplin in our next blog.