Edition: 2015-07-30

The 20th century gave rise to all sorts of seemingly beneficial things, which, in light of the simultaneous rise in chronic non-infectious ailments, we might need to flag as candidates for re-examination, as potential concerning correlates even though not yet confirmed causes.

One of those 20th enhancements was the broad availability of inexpensive and effective antiperspirants and deodorants. Prior to that, about the best one could do was to mask body odor with strong scents and perfumes.

Body odor mainly arises from a process that starts at the apocrine sweat glands. Long thought to be just for temperature regulation, these glands may turn out to have a separate and important excretory function.

The odor results from bacterial action. The odor (and human olfactory response) varies with skin biome, genotype, phenotype, gender, environment/culture, circumstances and doubtless other factors. Humans have been adapted to this phenomenon forever, but as with the simple matter of wearing clothes, public displays of natural state have fallen into disfavor. The pejorative old expression "the great unwashed" probably captures the attitude of the historical upper classes, who could afford to manage their olfactory footprint.

Approaches to "fixing" the BO "problem" might include:

• Blocking the production of sweat.
  Aluminum-based antiperspirants do this. "Aluminium-based complexes react with the electrolytes in the sweat to form a gel plug in the duct of the sweat gland." This is probably not inherently a great idea, plus there's the concern about absorption of the aluminum in these compounds. If you are avoiding contact with aluminum(1) and its compounds, be aware that those "Thai crystal" deodorant sticks are alum, which despite claiming "no added aluminum" are entirely an aluminum compound.
• Making the sweat less tasty to the bugs by altering its chemistry or Ph.
  Baking soda (sodium bicarbonate) based products do this, and it may be the most benign option with reasonable economy, especially if they contain very little else, and only otherwise harmless ingredients. As I am current contemplating various brands, any insight from the readership would be appreciated.
• Killing the bacteria outright.
  Products with triclosan, parabens and tea tree oil (distillate of melaleuca alternifolia) do this. You don't want to use any products containing triclosan - and it is still distressingly common in topical and oral products. Parabens are under increasing criticism (cancer). Tea tree oil works, but many people are allergic to it, or develop an allergy from routine use of it. Even with a natural antibiotic like tea tree oil, we need to consider the question of: is it really wise to routinely nuke regions of the skin biome? Furthermore, you will absorb some of the antibiotic(2).
• Neutralizing the bacterial byproducts.
  Casual research didn't turn up any products doing this.
• Masking the odor.
  This usually doesn't work long, if at all.
• Replacing the Bacteria.
  Dr. Mercola has a 2015-01 post on this, and the topic as a whole:
  Antiperspirants Can Make You Smell Worse by Altering Armpit Bacteria
  The AOBiome product mentioned there is quite expensive, and has a long waiting list.
• Use Ammonia Oxidizing Bacteria.
  AOBiome has now launched their initial products under the Mother Dirt brand. I have no experience with them. These are being billed as skin probiotics.

In general, if you can avoid needing to use any odor control products at all, that's the way to go until more is understood about long term effects. Being retired, I have this luxury, but still need a product for hosting visitors and periodic mingling with the general populace.