Science Friday podcast recently reported about a new systemic review highlighting negative consequences of consuming artificial sweeteners. I should make it clear that this has nothing to do with the fear mongering you’ll see on alternative health sites. There’s no good evidence to show that artificial sweeteners cause neurological damage (at least that I’m aware of).
They interviewed the study author Prof. Susan Swithers from Purdue University. This was a systemic review that collated and reviewed data from relevant studies in the past five years, in other words some of the highest quality scientific evidence available (barring author bias).
Here are the points she made:
- Artificial sweeteners may confuse the brain that leads to metabolic derangements.
- Normally sweet taste is accompanied by increase in blood sugar level. And the brain uses the sweet taste to prepare for the arrival of sugar. Examples include secretion of digestive enzymes that breakdown carbohydrates and signaling the pancreas to release insulin. Let’s call this as metabolic response.
- Consuming artificially sweeteners doesn’t trigger this metabolic response. Over time this could uncouple sweet taste from the metabolic response.
- Uncoupling sweet taste from the metabolic response can weaken your body’s ability to deal with carbohydrates, leading to higher post-meal blood sugar and insulin levels, which can lead to metabolic syndrome and diabetes.
- Currently there’s not enough data to say how much artificial sweeteners you can safely consume, but she pointed out that the data shows the biggest increase in risk when you go from people who never consume artificial sweeteners to the lowest intake group. So even a few cans of diet soda per week can be problematic.
- It’s not that artificial sweeteners are dangerous per se; just that frequent consumption may cause the brain to unlearn responses that prevent metabolic damage.
So what does this have to do with acne? Well, there’s data to show insulin resistance and other similar metabolic derangement can contribute to acne, and insulin is one of the key hormones affecting acne. Anything you can do to reduce insulin level would generally be helpful in acne.
Diet sodas seem to be a way to have your cake and eat it too, in that they allow you to enjoy sodas without worrying about calories or excess sugar. That’s why I started drinking them. In the light of these findings, I have to rethink that decision.
While diet sodas are still much better than sugar sweetened beverages, they may have counter-intuitive and negative consequences. It seems that uncoupling sweet taste from the accompanying metabolic response delays insulin release and temporarily allows blood sugar level to increase too high. This is similar to what happens during the early stages of insulin resistance. When the first phase insulin response is not sufficient (due to insulin resistance) blood sugar level increases too high until the pancreas has time to release more insulin. This temporary increase in blood sugar level can significantly increase the risk of metabolic syndrome and diabetes.
I quickly looked over the paper and it seemed like Prof. Swithers’ conclusions were somewhat speculative. Data shows that people who consume diet sodas have higher risk of metabolic syndrome, diabetes and weight gain, but I’m not completely sold that it’s because of metabolic derangements. There’s still too much uncertainty in the data to conclusive say that.
That said the smart thing to do is to give up artificial sweeteners. Because in all the studies they were associated with negative effects and none of the studies showed positive effects from artificial sweeteners, especially when compared to water.
Oh, and I should make it clear this also applies to stevia. This is not so much about artificial sweeteners as it is about non-caloric sweeteners. Even the alt-med sweetheart stevia delivers sweet taste without calories, whether it’s artificial or natural is irrelevant.
So it looks like I have to give up my diet Coke. Because being open minded is a bit**, it demands obedience to data and evidence – not what you want to be true.
Link to the Science Friday episode where you can listen the interview (about 8 minutes).