The key to understanding natural deodorants is that these work in completely different ways.
Natural antiperspirants do not really stop us from sweating. Most contain cornstarch, baking soda and essential oils. These ingredients do not stop sweating. These ingredients absorb sweat to keep the area dry.
True antiperspirants that contain aluminum salts physically block the sweat ducts to prevent sweat secretion. Glycopyrrolate is a class of topical and oral medications called anticholinergics to reduce the amount of sweat produced.
Due to the difference in how these products work, I cannot find a study that says that natural antiperspirants are better. This is simply because its not really a fair comparison. Aluminum salts and glycopyrrolate will clearly perform better simply because they reduce the overall amount of sweat produced. Practically speaking, most people find that natural antiperspirants have improved over the years but can still be somewhat unpredictable in terms of effectiveness simply because their effectiveness depends on how much they can keep up with the overall sweat produced.
Crystal deodorants form a mineral layer on the skin to prevent the overgrowth of odor- causing bacteria. Although the traditional aluminum chloride is not found in this product, there is a different type of aluminum compound in these. Because it can take a few days for this to change the bacterial environment under the arms, it may not be as effective initially on odor but can gain effectiveness over time by reducing bacterial overgrowth.
The only case reports out on crystal deodorants are reflective of occasional cases of irritant reactions to the product.
If you are looking for an alternative to traditional antiperspirants, crystal is a reasonable option to try. Although still focused primarily on odor and not reducing sweat, many do find it is effective as a deodorant.
It is always such a difficult question as to whether it is worth the hype. The answer is completely based on the patient’s perspective. The overall answer is that it really has not been shown in epidemiological studies that breast cancer and traditional antiperspirants have a connection.
I have not seen convincing data to support trying other options. I have tried the natural products and find them to be unpredictable in terms of effectiveness. Some days they work, some they don’t.
That being said, it is important to do what makes you feel best. If you have a personal concern then by all means this is why the alternative market exists. These products can help those looking of a reasonable option. The other option is considering botulinum toxin injections under the arms to reduce sweat for 6-9 months.