1. You should be washing your bath towels after 3-4 uses.

Towels are probably one of the dirtiest things in your entire bathroom. After the first use, they start to accumulate bacteria, mold, and all of your dead skin cells. And washrags and face towels should be washed EVERY TIME you use them!
2. If you wear bras, you should be washing them after 6 uses, period.

TBH, you should really be washing the sweat and dead skin cells after three uses. But six uses is the absolute limit.
3. Jeans should be washed as little as possible — possibly never.

This is a somewhat controversial topic. Some experts recommend washing them as little as possible, or, like Levi's CEO, recommend never washing them. In fact, they believe it's actually a waste of water and that it damages the material. There's also a common belief that you can put your jeans in the freezer in order to kill possible bacteria and keep them in good condition.
Still other sources say that, at most, you should wash your jeans no more than once every two months, and that's only if you sweat a lot. Otherwise, they recommend doing so every six months, as long as you think they'll hold up.
4. You should wash, or at least change, your sheets on a weekly basis.

Suffice it to say that a lot of sweat, dust, and gross shit can accumulate in your bed, including bacteria, who love a good humid hideout, so this is important.
If you'd rather have sweet AND clean dreams, it's best wash your linens in hot water on a weekly basis. However, if you don't have the time, you can do it every two weeks.
5. You should be washing your workout clothes after each use.

Sweat and tight-fitting clothes makes for a bad combo when it comes to bacteria and yeast that can stick to your clothes and multiply. Plus, they smell!
6. Kitchen sponges should be replaced every week.

Otherwise, you won't actually be CLEANING your dishes as much as you'll be soaking them with germs. Even if you wring them out, you should boil used sponges or heat them up in the microwave on a daily basis.
7. Hand towels must be washed every two days.

According to microbiologists, you should change the hand towels at your place every two days. However, if you let them dry completely somewhere where they get good natural sunlight and airflow, they could hold on for a couple more days.
8. Pajamas should be washed after three uses.

Though if you shower before putting your nightclothes on, they can last for as long as a week. If you don't wash your PJs as much as you should, they could cause issues like acne or even infections.
9. Rinse your bathing suit, at the very least.
You don't always need to use detergent when washing your swimsuit, but it is crucial that you at least rinse it out with lots of water after you take it off. Think about it — this garment has been exposed to sweat, sunscreen, chlorine, and other chemicals. You'll want to get those out!
10. You shouldn't wash your hair with shampoo more than 2-3 times a week.

This will definitely depend on how greasy your hair gets, as well as the products you use. However, shampooing only two or three times a week is a good rule of thumb for keeping your hair healthy.
11. You have to wash your face twice every day day.

Do it when you wake up and before you go to sleep. These are the two times in the day when you need to wash your face. (Do it also whenever you've been working out or sweating a lot).
12. You should really clean any makeup brushes that come in direct contact with your face on a weekly basis.

This habit will help you stave off acne and other skin issues.
13. Also, eyeshadow brushes must be cleaned on a monthly basis.

Same goes for the ones you use for your eyebrows.
14. Underwear must be washed every time you take it off.

No exceptions, unless you want infections.
15. Your coats need to be washed once per season.

If you only wear a coat during the winter, just wash it before you put it away for the year. But, if you're wearing it a lot during the season and come in constant contact with dust and dirt, definitely feel free to wash it halfway through the season as well.
16. And here's some good (or maybe bad) news, depending on how you feel about showers: the ideal frequency for showering/bathing is every 2-3 days... or when you're really dirty.

If you're not sweaty or dirty, you don't REALLY need to shower. This advice comes from hundreds of doctors who say that bathing too often, specially with hot water, makes your skin dry and removes good bacteria and natural body oils that protect the skin.
Tl;dr, science says that you should take a shower when you really need it, or just every two or three days.
For more translated content and BuzzFeed International goodness, subscribe to Inter Webz: our new bi-weekly newsletter bringing you the best of the 'net from around the world.
Note: if you can’t see the signup box above, just go here to sign up.
This post was translated from Spanish.