Cotton in summer in a hot humid climate is an absolute nightmare especially for exercise, just gets wet heavy and clammy. I don't wear any cotton at all in summer, it's a recipe for failure. As for the odour problem, I myself find that some of the clothes are smell magnets, but not me personally. If I have a tech tshirt that smells I bleach it and if it continues to smell it gets binned,there are no brands just no name $10 shirts from uniqlo. Underpants, shorts get the same treatment, and in fact I change my undies on average 2-3 times a day in summer, I loathe being stuck in "damp' under garments.

As for merino wool, I can testify this stuff is amazing, I read stories of transoceanic racing yachts men wearing them for weeks without washing them and they didnt smell, I bought a long sleeve tshirt, it's my favourite shirt by far, it just does not smell, long ski trips are great I can really rely on it, it was however very expensive, but extremely soft and the thickness of merino wool is so fine, it is lower than the threshold that feels itchy to human skin. Magic stuff. Even if you buy just one you won't regret it. Like goose down is still unsurpassed by any artificial insulator there is no man made fabric that can match merino wool as fabric worn next to the skin. Funny that, nature schooling us clever humans once again

One more thing, the softest, and and warmest socks, you will ever buy are merino and possum blend, yes possum, they are an extremely destructive and most unwelcome introduced species in new Zealand and their fur isvery warm, it shares with polar bear fur the rare property of being hollow core, which is thermally superior. Strange socks, but warm beyond belief and they don't stink.

This is common and I'm afraid you'll need cotton-percentages of at least 80-85% in your clothing to prevent it. That's one thing I learned right from my mother (who knits for a living and knows just about any kind of wool you can and can't imagine). For underwear you'll want to go even further and get maybe max. 5-10% synthetic material for elasticity. Only natural materials can really breathe and that's just what you need. KD named one: merino. Baby-Alpaca is a great choice, too. But usually you will mostly find cotton. And yes, you'll have to look at the tag of every single cloth you find interesting. Anyhing below 80% natural cloth will probaböy make you sweat (and stink) more.

A couple of years ago, I heard an expert on the radio talking about synthetic, so-called "hypo-allergenic" bedding materials. She said that because of the regular structure of these synthetic fabrics, they provided a perfect breeding ground for microbes. Given that body odors are caused by the bacteria living in sweat, it makes sense to me that synthetic fabrics would smell worse than natural ones when you sweat in them.

Not all synthetic materials are created equal. The most common ones in use today (Under Armor, Nike Dri-Fit, etc) are pretty basic from a technological standpoint (because they are CHEAP to manufacture). There are other options, but how much 'better' they are depends on a number of factors.

Synthetic materials work by using hollow fibers that 'wick' (through capillary action) moisture off from your skin. This is a fast process, once liquid moisture is present, but it has the down side of creating lots of areas for bacterial growth. In old polypropylene base-layers it was nigh-impossible to clean all of the moisture channels, resulting in their notorious permanent stink. Modern fibers are able to be more effectively cleaned, but the smell will linger until washed. This is addressed by some manufactures by adding a small amount of silver to act as an antimicrobial agent. The down side is increased cost and some potential environmental risks (in manufacturing).

Natural materials transport moisture along the outside of their fibers. They are also more loosely packed, so moist vapor is able to pass trough, not just liquid. The end result is a slower 'wick' but without the need for liquid to build up on the skin. Many natural fibers (like wool and bamboo) have natural anti-microbial properties which allow multiple uses without the stink that synthetics develop. The down side is that detergents bond to the surface of these fibers and can reduce their performance over time. There are special tech-wash products out there for cleaning/restoring such high-end base layers.

A note on cotton Cotton loves to absorb moisture, which is why it makes a wonderful towel, but a terrible base-layer. Cotton socks/shirts/underwear are the utter bottom tier option for performance stuff. If you've ever removed your white cotton sock and gazed at pruney wet toes, you have seen it at work. Avoid cotton for anything where sweating may occur, as it can/will lead to blisters and general discomfort. Linen is better than cotton in nearly every respect (for warm weather casual wear).

Given that both material choices come in multiple weights, you can dismiss the "one is cooler/hotter than the other" argument; just buy the appropriate piece for your needs. What it comes down to is a question of environmental concern (synthetics are worse for the environment than naturals, because they have to be manufactured) versus performance needs (synthetics wick faster, insulate better than most natural fibers, etc) and comfort (natural fibers tend to 'feel' better for most people, i.e. not 'sticky').

In summation here is a small table to pull from.

==Synthetics==

• Pros:
  • Dry faster
  • Cheaper
  • Easier care
  • Availability
• Cons:
  • Environmental damage
  • Flammable/meltable
  • Require liquid sweat to build up
  • Feel 'sticky' when wet

==Naturals==

• Pros:
  • Transport vapor
  • Natural anti-stink
  • Long lasting
  • Comfort
• Cons:
  • Price
  • Higher maintenance
  • Specialty shops/online only

[Good brands to look at for Synthetics: ExOfficio, Patagonia, Mountain Hardwear] [Good brands to look at for wool: Ibex, Smart wool, icebreaker]

Yep -- stay away from polyester. Try some merino wool clothing?

This is interesting. I've been wearing a lot of synthetics and I've not really noticed excessive BO, but then I never even thought about the possibility. I'll have to keep an, err, nose out next time.

I'd stick to natural fabrics that allow better your skin to breathe like cotton, linen, wool, silk, rayon in 80% or higher with polyester and the like 20% or less.

I have never liked the marketed dry-weave polyester gym shorts/tops so switched to 90-100% cotton at the gym.

If you want to prevent urinary tract infections (never had one so far and shouldn't on Paleo/Primal) also wear cotton 90% or higher cotton underwear since synthetic low-breathing fabrics like polyester increase microbial growth.

I don't Cross-fit but the hubby and I used to reek and sweat a lot pre-Paleo/Primal at the gym. On Paleo/Primal body odor is down tremendously (use the Rock or Tom's of Maine deodorant now - all gluten-free) but shower daily with soap (twice in warmer weather) and use Gluten-Free/Soy-Free/Dairy-Free Savonnerie shampoo and conditioner twice a week after gym workout.

The irony is that after Paleo/Primal the hubby and I find more other non-Paleo/Primal people smell - and not just at the gym or subway! Maybe our senses have heightened but I think grains/carbs make people reek after all you can smell alcohol in sweat and that is all carb!

in my case its absolutely reverse!!! natural fabrics make me smell really bad. but 100% synthetic fabrics no smell at all for many days!!!! why?? maybe those bacterias can grow in natural fabrics better!!!!

Had no BO issues with either natural or unnatural fibers. I've had better breatheability with some of the newer "performance" unnatural fibers, where cotton would be completely soaked.

I use a mix of coconut oil & baking soda, if you get the mixture just right it lasts the whole day and doesn't allow BO to form even after a long hot humid day. If I overdo the baking soda, it can cause rashes.

Just for extra insurance, I spray a bit of axe on the shirt itself, though this generally isn't needed.

Plain coconut oil by itself tends to not last very long and also can stain cotton, though detergent gets it out.

I can't find the article now, but I read in Men's Health or Women's Health that the moisture wicking fabrics needed to be washed with a "sport" detergent, like Tide Sport w/ febreeze to be able to penetrate the special water shedding fibers and get the odor out. They listed a couple of other brands of sport detergent too, but I can't remember them or find that article.

I have a couple of shirts that make me smell like Doritos. I have had to throw out shirts that always made me smell bad. I really liked that Bauhaus shirt....