Welcome to Bad Science on the Internet! Here, we highlight some of the crazy and sometime dangerous stuff people post online,  and then give you the facts.  

The bad science: Several companies are selling soaps that they claim can help you burn fat and lose weight. Not by eating it, just by washing with it. I’m totally serious, check it out here and here.

What do they claim? Here are some of the specific claims I found, rated by the level of scientific implausibility*:

1. “Seaweed is proven times and times again that is beneficial to general health

   

   and that can help with your weight loss either by consuming it or drinking it as tea, so it’s not that far fetched to assume it could do the same for your body through slimming soap.” Scientific implausibility score = 8/10. If eating or drinking it works (which is doesn’t), then rubbing it all over yourself must too, right?

2. “…extract from the deep seaweed soap has special penetrating and emulsifying properties that allow it to penetrate the skin by osmosis and react with the fat deposits that are directly stored beneath the skin and make them blood soluble.”  Scientific implausibility score = 8/10. This is nonsense, but I’m giving them credit for using the words “emulsifying” and “osmosis”.                                                                                                                                
3. “…the new dispensation can burn fatty and cellulite in the skin, promote skin metabolism, quick decomposing the surplus fat in the body for the discharge out of the body…” Scientific implausibility score = 9/10. The science here is as bad as the grammar.                                                                                                                                                                             
4. “…the main component of fat cells is water and seaweed extracts dehydrate the cells, thereby shrinking their appearance…” Scientific implausibility score = 10/10. First of all, water is not the main component of fat cells – it’s fat, which is right in the name and is literally the opposite of water. Secondly, even if the soap worked this way, how is it getting rid of the fat???

Are they trying to sell you something? Of course. These bars of soap will cost you $5-10 a piece.

Is any of this true? 

You can not melt away fat with soap, and if you could, it would probably be extremely painful. There is one, and only one way to loose weight, and that is to eat fewer calories than you burn.

It’s important to note that treating or toning cellulite is not that same as removing fat. Cellulite forms when  the “normal” structure of subcutaneous (under the skin) fat and connective tissue breaks down, causing a lumpy or ridged appearance to the skin. I put normal in quotation marks because cellulite is normal – almost all women will get cellulite at some point in their lives, and many men will as well. You can temporarily treat cellulite without actually removing the fat under the skin, so less visible cellulite does not mean that a person has also lost weight or fat.

Is any of this dangerous? Only to your wallet.

What’s the bottom line? Losing weight is hard. We’ve all been there. There is no easy way to do it – it’s all about eating fewer calories and/or excising more. If it sounds too good (and too easy) to be true, it surely is.

* Please excuse the poor grammar – it would appear that many of the folks selling these soaps are not native English speakers.