UNDERSHIRTS / UNDERWEAR / SOCKS
Ideally, clothes should be worn only once before washing. It is advisable to have an ample supply of clothing to avoid the need to turn underwear inside-out for another use. However, in situations where you run out of clean clothes and don't have time for a full wash, you can hand wash a pair in the sink at night and allow it to dry by morning.
T-SHIRTS AND GYM SHORTS
Optimal hygiene suggests wearing clothes only once before washing them. Clothes tend to absorb a significant amount of oil and sweat, creating an environment for bacteria to thrive, resulting in unpleasant odors.
You can wear your jeans multiple times before washing them, around 6 wears or even up to 6 months, as long as they don't smell bad. Research shows that after 300 wears, clothes won't have much more bacteria than after just 15 wears. If you get any stains, you can spot-clean them to keep your jeans fresh between washes.
KHAKI / CARGO SHORTS AND PANTS
For khakis, it's best to wash them every 2 to 4 wears. Unlike jeans, khakis don't conceal dirt as effectively and tend to absorb more sweat and body oil, making more frequent washing necessary to keep them clean and fresh.
BUTTON-DOWN SHIRTS AND SWEATERS
The number of wears between washing your clothes can vary, usually between 1 to 3 times. It depends on factors such as how tightly the garment fits, the weather, and the duration of wear. When you take off the clothes, check the armpits for any odor. If they don't smell, you can hang the shirt back or drape the sweater over a chair to air out, allowing you to wear them again later.
You can wear your sleepwear, like pajamas, for 1 to 3 nights before washing them, depending on how much you sweat during the night. Even though people might not realize it, they typically sweat around a liter each night while sleeping, so it's essential to consider personal comfort and hygiene when deciding how often to wash sleepwear.