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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! 

Click below to play Episode 23 or click “download” to save the MP3 file to your computer.

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?

LIL buy it now button

Buy your copy of It’s OK to Have Lead in Your Lipstick to learn more about:

  • Clever lies that the beauty companies tell you.
  • The straight scoop of which beauty myths are true and which are just urban legends.
  • Which ingredients are really scary and which ones are just scaremongering by the media to incite an irrational fear of chemicals.
  • How to tell the difference between the products that are really green and the ones that are just trying to get more of your hard earned money by labeling them “natural” or “organic.

Click here for all the The Beauty Brains podcasts.


Arm and Hammer Whitening Booster – how does it work?

Anonymous says…What’s the chemistry behind the Arm and Hammer Whitening Booster? What’s the chemistry behind the Arm and Hammer Whitening Booster? It’s a whitening gel that you layer on top of your normal toothpaste on your toothbrush. It’s very specific on the box (and the instructions on the bottle) that the whitening booster should only be used with fluoride toothpaste. Is there something in the gel that reacts to fluoride to whiten teeth? It’s inexpensive, so I’m a bit suspicious.

The Beauty Brains respond:

The chemistry of this product is pretty basic – it consists of gelled hydrogen peroxide which is a proven tooth whitener. As the peroxide breaks down it release oxygen which bleaches the tooth enamel. As far as I can tell there’s nothing in that reaction that requires fluoride so I’m not sure why they so emphatic about that. (Maybe it’s just to make sure that you don’t brush with this gel alone.)

The product also make a couple of other noteworthy claims:

3x more whitening ingredient than the leading whitening strip

This is the most interesting claim to me. Adding a peroxide gel to your brushing routine puts peroxide in contact with your teeth for only about 2 minutes every time you brush versus strips which hold the peroxide against your teeth for 30 minutes or so. That begs the question, which works better – a higher level of peroxide for a shorter period of time or a lower level for a longer period of time? I don’t know the answer but my guess is that if this method worked better they would have done the testing to make that claim rather than just claiming that it contains more active. More is not necessarily better.

The easier, faster way to whiten

It’s certainly quicker and more convenient because it only requires a small addition to your normal brushing routine. (I find it a pain to use those strips). Of course that doesn’t mean it works better or even that it works equally well.

Peroxide formula with patented liquid calcium

If this formula is patented it could be because the product offers some unique competitive advantage. Or, they could just be referring to this patent which discloses a special form of dicalcium phosphate that is more compatible with water soluble fluoride salts (apparently as toothpastes age, the monosodium fluoride reacts with dicalcum phosphate and becomes less water souble. This special type of DCP solves that problem but I don’t see what that has to do with how this Whitening Booster works.

By the way, the cost doesn’t surprise me (about $6 for a 2.5 ounces) because none of these ingredients are particularly expensive.

Arm & Hammer Whitening Booster ingredients

Water , Glycerin , Poloxamer 407 , PEG 32 , Hydrogen Peroxide , Phosphoric Acid , Dicalcium Phosphate

A final note: This question didn’t really come from “Anonymous” but I lost the name of whoever submitted it through Facebook. If you read this, whoever you are, please leave a comment with your name so we can recognize you for submitting an interesting question!


Beauty Science News – March 23

More beauty science news stories for your enjoyment…

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Vanicream Moisturizing Skin Cream – Look at the label

Vanicream is an elegantly simple formula that is particularly well suited for sensitive skin. Why? Let’s look at the label…

This product only contains a few ingredients that are relatively inert and it doesn’t contain the usual suspects that can irritate skin such as anionic surfactants and fragrance. It’s even free of “typical” preservatives such as parabens and Methylisothiazolinone, instead it uses a combination of sorbic acid and BHT. If the product was packaged in an open mouth jar I’d be worried these preservatives aren’t robust enough to protect it from the microbes introduced when you dip your fingers into the product. Fortunately it’s packaged with a pump dispenser which provides some added protection against contamination.

The moisturizing ingredients are petrolatum, which provides an effective barrier to moisture loss, and sorbitol, which is a humectant that will help bind water to the skin.

Vanicream Ingredients

Purified Water, White Petrolatum, Cetearyl Alcohol and Ceteareth-20, Sorbitol Solution, Propylene Glycol, Simethicone, Glyceryl Monostearte, Polyethylene Glycol Monostearate, Sorbic Acid and BHT

If you’re looking for a simple, mild moisturizer you can shop for Vanicream using our link and support the Beauty Brains at the same time. Thanks!


Vintage cosmetic video – can makeup make skin better?

Even though this commercial is listed on YouTube under “vintage cosmetics” it’s only three years old. I guess vintage is in the eye of the beholder. Nonetheless it does contain a very interesting claim that one normally doesn’t see associated with makeup.

According to Jennifer Garner “It makes your skin look better even after you take it off.” She then offers this fact as proof: “98% of women saw improvement in skin’s natural texture. tone, and clarity.” How is this possible? Can makeup really make skin healthier?

The answer probably has something to do with the product’s active ingredient, titanium dioxide. You see, this product has an SPF of 20. So it’s not hard to imagine a test which could show that skin that has been protected with this product is in better condition than bare skin.

Of course the commercial gives no indication of HOW MUCH of an improvement women saw. Still, it’s a clever execution of an ingredient based claim.

And just think, in only another 17 years this product really WILL be vintage!


Questions about oils and scrubs

Alisa asks…Will cleansing oil method clog pores, thus causing breakouts? Do we really need to double cleanse our face daily (even with or without makeup)? Or is it sufficient enough to just merely use cleansing oil to wash our faces? 2. Can we use olive oil as a serum before applying moisturizer? Is it effective? Or should we apply it after moisturizer? Is it true that chemical/enzyme exfoliation is the best way of exfoliating dead skin cells? I was told that apricot or sugar scrub wasn’t good for the skin, whereas jojoba scrub was a better preference. Why? I didn’t know if there’s any scientific reason behind it. Would love to hear your comments on the best scrub for face.

The Beauty Brains respond: 

1. There’s no single, absolute answer to this question. Some oils are comedogenic (meaning they tend to clog pores); other oils are not. That means that some oil cleansers will probably be fine on your face while others may cause problems. Unfortunately, the science of determining how likely a product is to clog pores is not very exact. Look for one that says “noncomedogenic” on the label and hopefully you won’t have any problems.

2. Many people swear by using olive oil (both before and after moisturizing.) It’s more of a matter of personal taste than anything else.

3. Chemical exfoliation (with an AHA) is the most proven way to exfoliate. Enzymes are not very stable and maybe become inactive in a formula due to heat and other factors. Scrubs certainly exfoliate too but sharp crystals (from sugar and salt) as well as pit fragments (from apricot) can scratch your skin. Many people get good results using jojoba beads because they are made of a soft wax like material. They won’t exfoliate as well as an AHA but they will be more gentle.


Does Revita Cor treatment really stimulate hair growth?

Brett asks…I’m interested in hearing your thoughts on the safety/effectiveness of the combination of products for hair thinning by DS Laboratories.  They mention the use of several ingredients such as spin traps and stem cells which I’ve never heard of being used in consumer products before. Are these safe? Is it even legal to use stem cells in this manner?

The Beauty Brains respond:

I took a look at the DS Laboratories website for and found information on their Revita COR treatment which uses the ingredients you mentioned. There appears to be two key points to the central premise of this “breakthrough” product: First, the product contains stem cells to stimulate hair growth (along with other “protective, nutritional and advanced conditioning compounds.”) Second, the ingredients are delivered via bioadhesive capsules which makes them more effective.

Stem cells and other ingredients

Revita.COR claims to “stimulate human hair follicle development and growth by incorporating cutting-edge plant-based stem cells.” They start with a legitimate scientific explanation that human stem cells in the epidermis differentiate to form hair follicles (and other skin structures.) Then, they make the unscientific leap that adding PLANT stem cells to your skin will somehow affect their follicles. They say “in experiments conducted on hair follicles, plant-based stem-cell extracts rejuvenate follicular cells and delay their senescence” yet they provide no reference or link to any such studies. Even if they have done such studies I suspect they were in vitro tests done on cultured cells in the lab rather than testing the effect of their finished on real people.

What about “spin traps” and all the other ingredients?

DS laboratories certainly make the product look impressive by adding ingredients like antioxidants, free radical scavengers, and anti-inflammatories that have been shown to have an effect in lab studies when tested on cell cultures. That kind of testing doesn’t mean these ingredients will provide any benefit from a rinse off conditioner.

If this product is really such a breakthrough then the company should be able to produce the results of a peer reviewed, double blind, placebo controlled study demonstrating the product really works when applied to real people. Without this kind of evidence I’m highly skeptical that it does anything special. Having said that, if DS Labs would care to share such study results that shows the product really works, I’d gladly reverse my position and help to promote their product.

Biocapsule delivery

So what’s up with these bio-adhesive microspheres? Supposedly they do a better job of delivering active ingredients (either by delivering the ingredients deeper inside the hair or skin or by anchoring it better to the surface of hair and skin.)  But this is not a new or exclusive technology because a number of suppliers offer different encapsulating technologies. The website cites studies that make it sound like they were done for this product but I suspect they’re just citing studies done by other companies with other materials. Why do I say that? Because, regarding the first clinical trial, they say they analyzed hair samples using “gas chromatography, mass spectrometry, measurement of fragrance in the headspace, and subjective evaluation by a panel of olfactory experts.” In other words, they were just measuring fragrance deposition which has nothing to do with hair growth ingredients.

The second clinical study showed that a biocapsule-based lotion, which was left on skin, did a better job of delivering ingredients. But since the product in question is a rinse off treatment what does this study really prove?

Is is safe or legal?

I see no reason to suspect the product isn’t safe. (And by law, it’s illegal to market products which are NOT safe.) And, there’s certainly nothing illegal about selling a cosmetic product with plant stem cells. (There are several others on the market.)

The Beauty Brains bottom line

It appears to me that they’re taking a real technology (bioadhesive capsules) and applying it to their hair growth product but they don’t present ANY evidence that it delivers their specific, active ingredients. Furthermore, there’s no direct evidence that these stem cells actually grow hair.

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Do you know how cosmetics can change the acid balance of your skin? Then you should listen to this episode! Plus this week we begin a brand new feature: a game called Beauty Science or  Bull Sh*t.

Click below to play Episode 22 or click “download” to save the MP3 file to your computer.

Show notes

Beauty Science or Bull Sh*t

In this new game, I give Perry 3 beauty science news stories and he has to tell the real from the fake. You can play along at home – just hit the pause button before I give the answer and see if you can outsmart Perry. Here are this week’s headlines, can you tell which one is TRUE?

1. Researchers have developed a vegetable alternative to petroleum based aerosol propellants.
2. Researchers have created the first detailed 3D model of curly hair.
3. Researchers have increased skin lotion stability with oil droplets shaped like hamburger buns.

Question of the week: Does the skin’s acid mantle affect how AHA products work?

BrainyBimbo asks…I’ve been told hydroxy acid products have to be in a certain pH range to work. But I’ve used products that were NOT in that range and they seemed to work for me. Is it possible that my personal skin acid mantle changed the pH of the products so they would work?

To answer that we’ll explain three things:
1. How AHA and BHA products work
2. What the acid mantle of skin is
3. How the acid mantle changes with pH

How Hydroxy Acids work

AHAs and BHAs are chemicals with a carboxylic acid group (COOH) and a hydroxyl group (OH)

Hydroxy acids loosen dead cells to smooth and plasticize skin.

The pH of hydroxy acid and other products

  • Hydroxy acid cleaners and lotions: 3-4
  • Liquid cleansers: 5-7
  • Syndet bars: 5-7
  • True Soaps: 9-10

So what’s the deal with this acid mantle?

Just think of it as a thin protective film that covers your skin. Your body generates it from three different sources:

  • From sweat: lactic acid secreted by sweat glands along with various amino acids
  • From sebum: which is the oil produced by the sebaceous glands. This oil water proofs the skin and it’s also broken down by enzymes on the skin’s surface to form free fatty acids.
  • From dead skin: additional amino acids and pyrollidone carboxylic acid which is part of the skin’s natural moisturizing factor.

So when this oily, acidic soup gets all mixed up and is spread across the surface of your skin, it has a pH between 4.5 and 5.5 and that’s why it’s called the acid mantle.

3 functions of the acid mantle

1. Physically shield skin from the elements (wind, cold, water)
because it water proofs the skin helps keep the skin cells tight and flat so it’s harder for bacteria to penetrate your skin.

2. Provide direct protection against alkaline substances
Since the mantle is acidic it will neutralize any contaminants and other chemicals that are alkaline (that have a high pH)

3. Provide indirect protection from microbes (bacteria, fungi, and viruses)
The microbes not only have to penetrate the mantle itself but the low pH of the mantle keeps skin cells tight and flat so it’s even harder for microbes to penetrate the skin.

Now, If the mantle is washed away or neutralized by alkaline agents then the skin is more easily damaged or infected. That’s because, without the mantle, the skin cells start to separate and allow more moisture loss which in turn causes tiny cracks in the skin where bacteria can enter.  Once the mantle is depleted and the pH of skin gets above 6.5 you’re much more prone to damage and infection.

Factors which disrupt the acid mantle

  • Environmental conditions like sunlight, water exposure
  • Diet – if you’re undernourished your body won’t produce all the right essential fatty acids.
  • Skin diseases – for example iacute eczema can raise the pH of your skin as high as 7.5 which is beyond  that protective range. To some extent the same is true for conditions like contact dermatitis which you can get from exposure to cleansing agents.
  • Systemic diseases like diabetes and some vascular diseases also increase skin pH
  • Topical product use can damage the mantle.

The mantle will restore itself but it takes time

Once damaged, it can take up to 14 hours to restore, by which time, it’s most likely under assault again from another washing. Most people wash their hands about three times a day, on average. Single washings shift pH to the alkaline region, which can shift back to normal within a few hours.

The acid mantle can NOT lower below its own pH

Hydroxy acids need to be at pH 3-4.
Acid mantle is at pH 4.5-5.5
The acid mantle can make the pH lower than its own.
Therefore, the acid mantle can’t make higher hydroxy acids work.

Will the acid mantle lower the pH of non-acidic products?

If AHA products need to be at 3 to 4 to work and they start at 6 or 7, your acid mantle will not buffer the products that low.

The bottom line: Take care of your acid mantle

The acid mantle is a powerful skin protectant and it’s important not to overstress your skin’s acid mantle or it will lose some of its protective ability.  However, you can’t rely on it to make a poorly formulated AHA product work better.


pH of common cleaning supplies http://housekeeping.about.com/od/environment/tp/Ph-Levels-For-Common-Cleaning-Supplies.htm

Study of the effects of cosmetic formulations with or without hydroxy acids on hairless mouse epidermis by histopathologic, morphometric, and stereo logic…Lúcia Helena Terenciani Rodrigues , Patricia M. B. G. Maia Campos
2002, Vol 53pp 269



LIL buy it now button

Buy your copy of It’s OK to Have Lead in Your Lipstick to learn more about:

  • Clever lies that the beauty companies tell you.
  • The straight scoop of which beauty myths are true and which are just urban legends.
  • Which ingredients are really scary and which ones are just scaremongering by the media to incite an irrational fear of chemicals.
  • How to tell the difference between the products that are really green and the ones that are just trying to get more of your hard earned money by labeling them “natural” or “organic.

Click here for all the The Beauty Brains podcasts.

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Is Oil Pulling really good for you?

Klennerable questions…I saw a post on Pinterest talking about oil pulling. It claims that it takes toxins out by washing your mouth with either vegetable oil or virgin coconut oil. This one girl even said that she lost weight and her teeth got whiter.. Are there any advantages to oil pulling?

The Beauty Brains responds:

This is the first time I’ve heard weight-loss claims attributed to oil pulling but this ancient process is widely claimed to help detoxify the body. While I put absolutely no faith in the anecdotal claims of these detox benefits there does appear to be some evidence that the procedure has a positive impact on oral health.

Test results for oil pulling

One study shows swishing sesame oil in the mouth improves reduces gingivitis and plaque. There was a net decline in mean plaque scores from baseline to 45 days amounting to 0.81±0.41 (p<0.01). Another study, as reported by the British Dental Association, shows that “pulling” with coconut oil can reduce cavities. They found that that “coconut oil strongly inhibited the growth of most strains of Streptococcus bacteria including Streptococcus mutans – a major cause of caries.” However, the coconut oil may need to be “pre-digested” with an enzyme to make it most effective.

The Beauty Brains bottom line

Getting rid of toxins by oil pulling is a myth but it may provide benefits to your teeth and gums. Talk with your dentist for a better understanding of how to make oil pulling a part of your complete oral health regimen.


http://www.johcd.org/pdf/Effect_of_Oil_Pulling_on_Plaque_and_Gingivitis.pdf J Oral Health Comm Dent 2007 ;1(1):12-18


TD Anand, C Pothiraj, RM Gopinath, et al. Effect of oil-pulling on dental caries causing bacteria. African Journal of Microbiology Research, Vol 2:3 pp 63-66, MAR 2008. < TD Anand, C Pothiraj, RM Gopinath, et al. Effect of oil-pulling on dental caries causing bacteria


Beauty Science News – March 16

Here are 5 of our favorite beauty science news stories from this week….


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