Beauty Bullshit: Fat Girl Slim

Reader Corbyn Wild wrote, “Love the Beauty Bullshit posts! Ever think about looking at the Fat Girl Slim products? They seem to be based on pseudo-science and buzzwords at best but who knows maybe they are legit! I know a fab scientist (YOU) that could clarify that for her adoring public (ME).”

Despite the bizarre and somewhat misleading name, Fat Girl Slim “is not a weight-loss product”. Rather, this product claims to “reduce the appearance of cellulite with [an] advanced formula that fits perfectly into your body-bettering routine. QuSome—powerful, encapsulated caffeine molecules—ensures targeted delivery and firm, smooth results.“Caffeine is used in other skincare regimes as well: Caffeine-based products are touted to do everything from lengthen your eyelashes to eliminating dark circles under your eyes.

To evaluate this product, first we need to establish what caffeine is. Caffeine is an alkaloid molecule that produces a stimulant effect when ingested. When you consume caffeine in coffee, soda, or the like, it basically fucks up the job of an inhibitory neurotransmitter called adenosine by acting as a competitive inhibitor. This means that caffeine binds to adenosine receptors without activating them. As a result, adenosine just sort of has to hang out at the synapse, unable to bind and thus unable to get shit done. Because adenosine inhibits the central nervous system, and caffeine acts as an adenosine antagonist, inhibiting its action, caffeine increases the activity of the central nervous system.
Next, we need to establish exactly what cellulite is. Cellulite is a condition of subcutaneous fat that causes a dimpling effect under the skin. Under men’s skin, the connective tissue is criss-crossed, ensuring that cellulite (probably) does not bulge out. For women, the tissue is organized into a column shape, allowing for cellulite to appear. Combine that with a tendency towards thinner skin and a higher percentage of body fat, and it’s hardly surprising that women are more likely to show cellulite than men are. As a result, an estimated 90% of women experience cellulite post-adolescence. It’s so ubiquitous among ladyfolk that some doctors have even proposed that cellulite qualifies as a secondary sex characteristic, right up there with breasts, hips, and pubic hair.

Although various treatment methods have been proposed for treating cellulite, a solution to the supposed problem is remarkably elusive (even liposuction is unable to address this issue, as one’s connective tissue and skin thickness aren’t changed by the procedure).

So, why the claim that caffeine will fix your cellulite woes?
The theory behind the claim has to do with another key feature of adenosine action: adenosine increases blood flow through the A2A and A2B receptors on the vascular smooth muscle. As a result, caffeine can sometimes cause blood vessels to constrict.

Unlike many, many topical treatments for various ailments of unsexiness, caffeine is absorbed into the skin at low levels, with a rate of about 2.24+/-1.43 micrograms per centimeter squared per hour. Fat Girl Slim uses a technology called QuSomes to deliver caffeine to your skin. A QuSome is basically a cheapo version of a liposome. Liposomes are are synthetic vesicles comprised of a lipid bilayer, just like your cell membranes. (Since I recently wrote about micelles– don’t confuse them! Micelles are a monolayer.) Liposomes are most empirically supported for cancer treatments, although there is some evidence of their efficacy for topical drug dispersal as well. Although I am not certain whether the concentration of QuSomes in Fat Girl Slim will facilitate a meaningful effect on blood vessel constriction, there is nothing suspicious about this dispersal method prima facie. (It is worth noting, though, that Fat Girl Slim is calling liposomes “molecules”– liposomes are many molecules. That is not what a molecule is.)
The problem is that blood vessel constriction will do fuck all for your cellulite. Indeed, other products also claiming to reduce cellulite, such as Orlane SOS Contouring, claim the exact fucking opposite: Orlane is certain that INCREASING blood flow will get rid of your cottage cheese rear end once and for all. The facts remain that cellulite is caused by connective tissue organization, skin thickness, and fat-possession.

Another proposed hypothesis for caffeine’s supposed cellulite-murdering effects is caffeine’s ability to stimulate lipolysis. Lipolysis is the body’s way of breaking down triglycerides (fat) into smaller hunks, such as diglycerides, monoglycerides, glycerol, and free fatty acids. Caffeine has the potential to start a signaling cascade that ends in lipolysis. Unfortunately, the only thing that’s clear in the scientific literature is that caffeine will cause you to lose a little bit of water. That isn’t a fix.


Finally, people have suggested that caffeine might help with cellulite because of its chemical similarity to aminophylline, another adenosine antagonist that is legitimately used as an asthma medication and illegitimately used as cellulite treatment. No independent research, however, has validated the idea that aminophylline does jack shit for cellulite. Indeed, the idea has been essentially disproven since 1999, when a study by Collis and colleagues found that aminophylline did no better than a placebo at reducing cellulite. The authors concluded, “The best subjective assessment, by the patients themselves, revealed that only 3 of 35 aminophylline-treated legs and 10 of 35 Endermologie-treated legs had their cellulite appearance improved. The authors do not believe that either of these two treatments is effective in improving the appearance of cellulite.” Thus, caffeine’s similarity to another placebo is hardly a point in its favor.

Woooo placebos!

So why do people give Fat Girl Slim decent reviews if its claims are a load of hooey? The Bliss website might help us out on that one: “Bliss suggests using in conjunction with regular exercise, a healthy diet, regular vigorous massage and the rest of the Bliss FatGirl Slim regimen.” I would save your hard earned-money and stick with the healthy diet and exercise. (It may or may not help your cellulite, but it’s a good idea either way!) If you’re still stressing about lumpy thighs, try to remember that you are so far from alone it’s almost laughable. They’re just lovely lady lumps (as Fergie might say).

If you have any beauty claims you want researched in future Beauty Bullshit blogs, feel free to leave them in the comments below.

1. Excellent post! I absolutely adore your approach to these beauty bullshit posts; they leave pretty much no doubt as to what products (and companies) are absolutely full of it. I feel like these claims are becoming almost competitively absurd.

I can see a new product blurb now: “Meet NOTALIE’s super genetically polarized happy cream with tree stem cells and silk powder! Our product literally absorbs through your skin and changes your genetic makeup to get rid of that pesky cellulite. Be smooth as silk!”

Which reminds me, TKB sells silk and pearl powder. I’m pretty sure that most of the claims are bullshit, but I’m wondering if either of these powders might affect products in a way beyond being just filler. Horribly vague and unhelpful, I know.

(I’d also be curious on your own thoughts about OCM, since while there are some undoubtedly zany claims about what it can do, there does seem to be some logic behind it. However, that’s really far off topic and probably something that would need a longer answer).

2. According to TKB, “the silk protein [in hydrolized silk powder] is absorbed into the skin or hair and improves moisture balance, suppleness, shine and elasticity. It imparts a silky, smooth feel to the skin,” whereas micronized silk powder “adds a sheen to your makeup products as the light is reflected,” “reflects and absorbs UV rays,” “is an oil absorbent,” and, most confusingly, “contains 18 amino acids which are easily absorbed into the skin…[and] is a natural moisture-adjusting product…which ‘breathes'” somehow. I’d say that it feels soft.
As for pearl powder, TKB stresses that the following claims have not been approved by (and I assume not even evaluated) the FDA: “Absorption of our Authentic Pearl Powder is considered positive because the product contains 31% Calcium and 56% Protein as well as an assortment of amino acids. This is believed by some to be good for bone development, and to promote healthy, lustrous skin.” And while I assume that goddamn PEARL POWDER would be used to make makeup shiny, TKB says that it “will [not] give a pearly glow to your products, they are used for their health benefits…not their appearance.”
In layman’s terms, they’re filler that may feel better on the skin and are definitely oodles more expensive than talc.

3. How can something be reflected and absorbed at the same time…?

4. It clearly uses quantum mirroring. We should call CERN.

5. Have I mentioned that I love you guys?

I have been toying with the best way to deal with the OCM. I ideally would like to do a randomly assigned clinical trial, but I would definitely need to investigate whether or not I would need to find an IRB to approve it for ethical reasons… :/

6. If we could take the absorbing/reflecting properties out of that stuff I bet we could win a Nobel prize! I dunno what kind of things you would want to both absorb AND reflect.. but it would be impressive.

6. I love your blog, and I feel like every 5 seconds i check to see if there is a new post! Never stop! I think it would be cool if you did a post on any blogs that you go to, or you love.
Continue being so crazy awesome!!!

7. If only I didn’t have a job and could post all day!

8. This is amazing – you are too too funny. Given my newfound knowledge about caffeine, I’m now giving my iced coffee some serious side-eye.

Also, wonder if anyone out there has run an experiment with Orlane SOS Contouring on one cheek and FatGirlSlim on the other…

9. You would find nothing. I absolutely promise you, you would find nothing.

10. They also seem to sell a device that… vibrates the fat away? I am reminded of these machines that were in some salons in the 1980s that had a bunch of knobby rollers on a big rotating drum. One was supposed to press one’s abdomen, leg, butt against it as it spun to massage the bumpiness away. I am just sort of generally offended by the fat girl slim line, makes me want to avoid their other products.

11. Ha! That’s absurd as well.

12. Emma – I think you mean something like this:

Those roller things have been around for years. I think if they work at all it would only be through some temporary swelling that reduces the appearance of cellulite. There was one around from the 80’s that strapped on somehow and looked really painful and pinchy. – great post as always. I appreciate the “fuck all” summary of the effects of caffeine on cellulite. I am curious – has there ever been a Beauty Bullshit post that found validity to the claims made for a product?

13. Only one so far:

14. THANK YOU SO MUCH FOR DOING THIS POST! I feel internet famous! Awesome post by the by…really cleared up the way cellulite busting products work and why are bodies develop those lovely lady lumps! I’ll pocket the cash and buy some Paul and Joe products instead 🙂

15. They’ll certainly be much cuter!

16. Beauty Bullshit request (also first time commenter, HELLO!!! I’m freaking obsessed with your blog and just read the entirety of it over the past few days instead of doing grad work like I was supposed to)

The Julep Oxygen Nail Treatment. Bullshit?
Also, how do I take off nail polish without my nails peeling. They look like crap right now, which is why I’m about to use the oxygen nail treatment. Is that actual nail or just residual schmutz being removed?

17. I would have to look into it for you…

18. I am super late to the party (catching up on all your posts), but I would love for you to address how every hair tool ever is now boasting it’s modern ‘ionic technology!’×217-1020×217.jpg

My husband says this is the stupidest shit ever, as basically anything using heat is using ‘ionic technology’ as it basically translates to ‘blows hot air!’, and this is not anything to tout as new or amazing. But then I see shit like this:–faqinfo-6_27-185.html

And I’m like… it’s time to ask

19. That’s a good one!