If you are looking for information on whether sugar causes acne, click this link.
This page finally wipes out the ridiculous notion that diet has nothing to do with acne.
It isn’t just me rambling. This is actually backed by credible science. Most of the material here is from Dr. Loren Cordain’s paper ‘Implications for the Role of Diet in Acne‘ (available here).
I’m summarizing the study here and translating it from medical jargon to plain English so that you don’t have to get a PhD just to understand it.
Basically Dr. Cordain is saying that fluctuations in blood sugar level cause acne by:
- Increasing sebum production
- Causing skin cells regenerate faster
- Causing dead skin cells to stick together
Faster regeneration of skin cells means that more dead skin cells have to be pushed through skin pores. By the way, it also means faster aging of skin. When dead skin cells stick together they have to be pushed through skin pores in big lumps instead of single skin cells. It’s like diverting heavy truck traffic through a narrow village road. That can only mean traffic jams.
Throw in a good measure of sticky sebum and I’m sure you understand that it can only mean one thing: clogged skin pores and acne.
This picture summarizes the whole thing.
Click the picture to enlarge (opens in a new window)
The red line shows what happens to your blood sugar levels when you eat foods with high glycemic load (GL). The green line shows the same for low GL foods. Glycemic load is a measure of how much a particular food increases your blood sugar levels (BL).
Eating high GL foods spikes your BL levels. The pancreas responds by releasing large quantities of insulin to bring down the bloodsugar levels. It has to do this because high BL are dangerous.
Large quantities of insulin cause BL to plummet. Too low blood sugar levels trigger another emergency response. The adrenalin glands release androgens. Androgens are hormones that signal the liver to release some of its glycogen storages to raise the BL. Too low BL levels can lead to unconsciousness.
Incidentally low BL levels also trigger serious sugar cravings. With these cravings hammering the back of your head it’s likely that you’ll grab something sweet (=high GL) and repeat the process.
If this would happen only once in a while it wouldn’t be a problem. Unfortunately our modern diets are full of processed foods filled with refined carbs and sugar. So this becomes a daily cycle.
The more the pancreas releases insulin the less effective it becomes. Cells don’t respond to it anymore so well. This is called insulin resistivity or reduced insulin sensitivity. To counter this effect the pancreas has to release larger quantities of insulin.
Fats further add to the insult. Diet high in fats (like our modern diets are) leads to high levels of fat in the blood stream. Fats literally coats the sugar and insulin molecules and makes it harder for them to connect – further reducing insulin sensitivity.
So now you have this escalating cycle where more and more insulin is circulating your blood stream. If (and when) the blood sugar levels swing you also get a steady supply of androgens.
Insulin never works alone. It’s a precursor to practically all the hormones in your body and always affects other hormones also. In this case we are interested of insulin-like growth factor 1 (IGF-1) and insulin-like growth factor binding protein 3 (IGFBP-3). When insulin levels go up IGF-1 follows the lead but IGFBP-3 levels drop.
So how does this cause acne.
Well insulin, IGF-1 and androgens all increase sebum production. IGF-1 is actually a growth hormone and it increases the rate at which skin cells regenerate. IGFBP-3 facilitates separation of skin cells when they die. So now you have a steady supply of three hormones that all increase sebum production. More of one hormone that makes skin cells grow regenerate and die faster. And less of one hormone that actually causes the skin cells to separate when they die.
As we discussed above, all that means more traffic jams, clogged pores and acne.
As I mentioned in the what causes acne page this is just a part of the equation. Take a look at the following quote:
Despite there being a correlation of acne with elevated IGF-1 and DHEAS (type of androgen), it would be difficult to use these hormones as laboratory markers of adult acne in the clinical setting because levels are usually within the normal range. Undoubtedly, these hormones have important effects in other organ systems in the adult in addition to effects in the skin, and therefore nonspecific inhibition of hormone synthesis could have undesirable effects.Correlation Between Serum Levels of Insulin-like Growth Factor 1, Dehydroepiandrosterone Sulfate, and Dihydrotestosterone and Acne Lesion Counts in Adult Women – Mark Cappel, MD; David Mauger, PhD; Diane Thiboutot, MD ARCH DERMATOL/VOL 141, MAR 2005
In plain English that means that IGF-1 and androgen levels cause acne in acne prone individuals, but the levels are roughly the same both for people with and without acne. Some, yet unknown, factorworks behind the scenes to cause acne.