Can you get rid of cellulite by rubbing coffee grounds on your thighs? Find out in this week’s episode. Special bonus: Listen to Perry rant about Harvard spreading misinformation on cosmetic safety!
Show notes
Beauty Science News: Harvard says harmful untested chemicals rife in personal care products
Here’s the link to the article that sent Perry into a frenzy.
Question of the week: Can I make a DIY cellulite scrub? with coffee grounds?
Heather asks…Can a DIY coffee bean scrub can reduce cellulite?
According to an article from PopSugar you can “take down cellulite with this DIY coffee bean scrub.” The scrub is made of Coffee grounds, sugar and coconut oil. Massage into your skin, rinse it away and the caffeine will reduce the appearance of cellulite. Will this really work? First let’s look at caffeine to see if it really is effective against cellulite and then we’ll look at this coffee bean scrub to see how well it delivers caffeine to your skin.
We’ll start by asking the three “Kligman questions” about caffeine:
1. Is there a scientifically proven way that the ingredient could work?
2. Can the ingredient penetrate skin to get to where it needs to work?
3. Are there any controlled studies showing the ingredient really works when applied to skin?
Is there any known mechanism for caffeine reducing cellulite?
Yes there is a proposed mechanism. It’s a little complicated so to explain the biochemical pathways involved we’ll abbreviate the chemical names here and we’ll post the full names in the show notes.
To get rid of cellulite you need to increase lypolysis which is the breaking down of fat. And lypolysis is controlled by an enzyme called HSL. HSL is activated by a material called PKA (Protein Kinase A). You can increase the amount of available PKA by controlling cyclic AMP (cyclic Adenosine MonoPhosphate.) But an enzyme called PDE (PhosphoDiEsterase) breaks down cyclic AMP. So to get rid of cellulite you need to get rid of PDE And guess what, caffeine is a PDE inhibitor.
So theoretically caffeine reduces PDE which gives you more cAMP which means more PKA which activates more HSL which breaks down more cellulite deposits.
Does caffeine penetrate skin?
Yes! A search on Pubmed shows over 50 studies involving skin penetration of caffeine with number of different variables:
- Different vehicles (water, alcohol, gel.)
- Different substrates (In vitro, in vivo and ex vivo testing.)
- Different methods (like tape stripping or Raman spectroscopy.)
- Different skin conditions (intact skin, barrier impaired skin, skin with and without hair follicles.)
No doubt that it penetrates but how much and how fast varies with the method and vehicle. For example, small amounts in alcohol show penetration in as little as 5 minutes. Larger amounts from a gel base take up to 6 hours. So there’s a range of absorption behavior.
Are there any legitimate studies proving caffeine works when rubbed on skin?
When we say “legit” studies here’s what we mean:
- in vivo (meaning on people, not just tested on skin cells)
- Placebo controlled (meaning if one thigh was treated with a cream with caffeine then the other side is treated with the same cream without the caffeine)
- Double blinded (meaning neither the subject nor the researcher knew which was the the “test” and which was the “control” side received the treatment)
- Peer reviewed (meaning the results where published in a scientific journal and the study was reviewed by other scientists)
So are there such studies on caffeine? No. But there are some in vivo studies that are worth of mention.
Study 1: tested 18 people, measured thigh circumference after 30 days of applying a “Slimming Complex” consisting of encapsulated caffeine, L carnatine and some other stuff to one thigh and nothing to the other thigh. Results showed a a reduction in thigh diameter of ranging from between 0 to 10mm.
Two problems with this study: They were testing a mix of caffeine and other ingredients which were encapsulated to enhance penetration. So it tells us nothing about caffeine alone. Also, there was no control. We know that just massaging skin can have a slimming effect so there’s no way to know how much of the effect of the cream was from just massage.
Study 2: Another study was placebo controlled and it evaluated a mix of caffeine, retinol and ruscogenine. They used more sophisticated measuring techniques:
- Used digital imaging to measure the “orange skin” type bumpiness. The test product showed a 53% improvement, the placebo a 14% improvement.
- 3D Ultrasonic imaging to measure thickness of dermis and hypodermis: Both test product and placebo showed some improvement.
- A cutometer to measure mechanical properties of skin. No diff between test and placebo.
- Laser Doppler Flowmetry to measure blood flow: The test product was better than placebo at increasing blood flow, even 1 month after test was over.
Problems with this study: Once again they were testing a cocktail of ingredients not caffeine alone. Also, the results didn’t show clear improvement on all parameters.
Study 3: In fact the only study that we could find on caffeine alone was not an in vivo study it was an ex vivo study done on swine skin. And it ONLY showed positive results when the caffeine was combined with ultrasonic waves. Caffeine alone did nothing.
So there are no high quality studies (that we could find) which where done with caffeine alone that clearly indicate an anti-cellulite effect.
We did learn, however, that in all the slimming studies we saw caffeine was used in the range of 3 to 7%. (7% is about the maximum solubility of caffeine in water). Which brings us to our next point. Even if caffeine does have some slight slimming effect by itself, will this DIY coffee bean scrub deliver it to skin?
Do coffee grounds have enough caffeine?
How much caffeine is in coffee grounds? Before brewing, ground coffee has somewhere around 5% caffeine. So dry coffee grounds have plenty of caffeine but it’s locked up in the grounds so it’s not available to enter your skin.
Used coffee grounds are moist enough to release caffeine but depending on how your processed them they may only have 0.5% caffeine left. (In other words, brewing coffee extracts about 90% of the caffeine from the ground beans.) Either way, using coffee grounds to deliver caffeine to skin is very ineffective.
Will this scrub deliver caffeine to the skin in a way that it can work?
As we said, caffeine is water soluble. By mixing the grounds with coconut oil you’re essentially blocking the caffeine from getting out of the grounds and into your skin.
Also, caffeine absorption takes time: Unlike many ingredients caffeine can penetrate skin, however it’s a slow process. The diffusion rate for a substantial amount of caffeine through human skin is 2.2 x 10-6 grams per centimeter squared of skin, per hour. So it will take an hour or two to get sufficient caffeine into your skin. No one leaves a scrub on that long.
The Beauty Brains bottom line
So IF you maximize the amount of caffeine left in the grounds by brewing weak coffee…
And IF you use the raw grounds (without oil that can block the caffeine from getting to your skin)…
And IF you massage the grounds on your skin…
And IF you leave the grounds on your skin as long as you can stand it…
And IF you repeat this daily for about month…
And IF the few studies that show a slimming effect are not an anomaly…
THEN you might see a slimming effect of up to 1/2 inch decrease in your thigh circumference. Would you even notice that difference?
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