You know me. I’m a sceptic.
If you want me to believe the extract from that rare blue flower that blooms only at midnight in the highland rainforest of some remote island will erase my wrinkles and make me look 10 years younger, you’d better have some scientific studies to back that up.
Serious scientific studies, I mean.
The kind done on real people. Lots of them.
Not the kind done in a petri dish. Those aren’t worth much. Here’s why:
In-vitro vs in-vivo
You can do scientific studies either in-vitro or in-vivo.
Vitro comes from Latin and its means “glass”. These studies are done on skin cells in a petri dish.
You can see the limitations, right? These studies can tell us how a substance works on isolated skin cells. But on your body, skin cells aren’t isolated.
So, just because in-vitro research says something is awesome, it doesn’t mean it is. Something that works well in-vitro may not work at all or even be harmful in-vivo.
In-vivo is on a real person. And studies done on real people often refute the findings of those done in a petri dish.In-vitro tests are done on skin cells in a petri dish, not on real people. Don't trust them!Click To Tweet
What Are The Limitations of in-vitro tests?
Skin cells on a petri dish aren’t attached to the rest of the body, obviously. So, when a study is done in-vitro, we have no way of knowing how deep an ingredient can penetrate the skin.
This is important for two reasons:
- The best skincare ingredients, such as retinol and vitamin C, have to penetrate the skin and reach the cells under the upper stratum corneum to work their magic. If they stayed on the surface, they wouldn’t do much.
- If something can penetrate the body, it could potentially be harmful to our health. Before we put something on our skin, we need to make sure that what gets in is safe and won’t cause problems.
In-vitro results don’t automatically translate in-vivo. That doesn’t make these tests useless. Some ingredients that showed promise in-vitro have turned out to work really well in-vivo too. But in-vitro results should ALWAYS be verified by in-vivo testing.
An example? Peptides.
Peptides are really hot right now. Brands are putting them everywhere, shouting from the rooftops how amazingly well they fight wrinkles.
What they don’t tell you?
These studies have been done almost always in-vitro. Does that mean they don’t work? Nope. They may work well indeed, but until I see these claims confirmed by in-vivo testing, you won’t find me splurging on a cream just because it has peptides.
The Bottom Line
Next time a cosmetic company trumpets a study to promote its products, look at the fine print. Was the study done in-vitro? If so, don’t buy the hype just yet. Wait till in-vivo research confirms (or refutes) those results. That’s when you know if something really works (or not).
Do you rely on scientific studies to tell you if a skincare products works or not? If so, how well do you trust in-vitro testing?