As with so many things, it depends!
When it comes to exfoliants, there is a lot to choose from! Here are a few:
- Salt (varying types & crystal sizes)
- Sugar (varying types & crystal sizes)
- Clays (varying types & particle sizes)
- Jojoba beads
- Coffee grounds
- Ground-up shells (apricot, walnut, etc.)
One of the first things you’ll want to consider is how abrasive the exfoliant is and where you intend on using it. Your face will have very different exfoliating needs than your feet! For this reason, I do not recommend using scrubs designed for the body on the face (too harsh!) or vice-versa (that would be too gentle).
You’ll also want to consider the solubility of your exfoliant. Is it water-soluble (sugar, table salt, Epsom salt, etc.), oil-soluble (jojoba beads), or insoluble (clays, apricot/walnut shells, pumice, poppy seeds, coffee grounds, etc.)? Insoluble exfoliants typically do well in any kind of formulation, but water and oil-soluble ones can dissolve if your formulation contains the appropriate solvent. If you’re making a scrub that contains water, I don’t recommend using salt or sugar as your exfoliant—they will dissolve into the water in the formulation (to some degree, at least—larger grain salts and sugars may retain some scrubbiness), and you will not get a scrubby end product. If you are working with jojoba beads you need to take care not to melt them.
Something to consider with insoluble exfoliants is the mess factor. Exfoliants like coffee grounds and poppy seeds won’t dissolve in bathwater and tend to remain in the tub after draining, leaving you to wash/rinse the tub after each use (also—will your exfoliant clog your drain?). You may also find high concentrations of insoluble exfoliants in bath products can be uncomfortable to sit on after they sink to the bottom of the tub.
When it comes to using salt instead of sugar; remember that salt can really sting on cuts and scrapes, while sugar doesn’t. It’s a personal preference, but if you are prone to scraping knees or cutting yourself while shaving, salt might not be the best choice for you!
You can also blend exfoliants; I’ve done this in the past with formulations like this one where the poppyseeds are blended with sugar. The sugar ends up being the primary exfoliant while the poppyseeds are more of a decorative element. I made this decision because the sugar will dissolve into the bathwater and wash down the drain nicely, while the poppy seeds can make a bit of a mess. More poppyseeds = more mess!
Another consideration if your formulation contains water: preservation. Some exfoliants, like coffee grounds or clays, can pose a preservation challenge, so you’ll need to be aware and test your preservation system to ensure it works with your overall formulation.
In the end, though, the best way to find out if it works is to try it yourself!
Posted in: Ingredients