It's a strange thing about being and adult — you think you've got the basic stuff figured out, but then one day you realize that you've been doing something wrong for ages.

Don't worry, it happens to all of us. The only time when it's really a problem is if that mistake is costing you money — or your health. Our bodies are complicated, and new information comes to the surface on a regular basis, so here are a few aspects of daily life that you might be getting wrong — and the whys and wherefores of doing them right.

1. Many of us are brushing our teeth wrong (I was!): I vaguely remember learning the proper brushing technique in school when I was a kid, but for whatever reason, it just didn't stick. ''Long horizontal strokes along the gumline can lead to abrasions," Michael Sesemann, DDS, president of the American Academy of Cosmetic Dentistry and an Omaha dentist told WebMD. "Aim your bristles at the gum line at a 45-degree angle and do short strokes or vibrations."

Keep in mind: Softly brush up and down your teeth, not across your teeth. And make sure you brush all tooth surfaces, including getting around all the molars in the back (starting here is a good way not to forget them). See the video below for a good visual on how to do this. 

2. It's important to give your eyes a break when you are using a computer or reading (on screen or off), but most people don't, and it can lead to poorer vision and eyestrain (this is a leading cause of headaches). Taking an eye break can be easy to forget, so think about setting a timer on your phone; once you get used to looking up and out every so often, it will become a habit and you won't need the reminder anymore.

  • It's easy to remember 20/20. Aim to look up every 20 minutes to a distance of at least 20 feet away.
  • You should also have your computer monitor set up properly — a good rule of thumb is that when sitting normally, you should be looking at the top of your monitor, so that while you are working, you are looking slightly down.
  • Set up your workstation so that glare from a window or overhead lights is minimized. (There are screens you can purchase online if you can't change your location.)
3. You are probably trying to get to sleep wrong. According to the National Sleep Foundation, about 22 percent of Americans experience insomnia most nights (if not every night), but nearly half of us (48 percent) experience insomnia at some point. If you are having trouble getting to sleep, it's important to address underlying issues like depression or disease. But if you are otherwise healthy, consider the following recommendations:
  • Don't fall asleep with the TV on, and ideally, don't look at any screen an hour before bed (if you must, set your brightness on a low setting — a blast of light into your eyes makes your brain think it's still daytime).
  • Don't eat a big meal at night, and if you do, give yourself at least three hours to digest before you hit the sack. Digestion can be a stimulant to your body (more or less so, depending on what you've eaten). If you can eat a large lunch and a small or light dinner, that should help you rest easier.
  • A pre-sleep deep breathing, gentle yoga, or meditation ritual can also be helpful to start turning the brain off, especially if a racing mind is what's keeping you up.
  • Of course, cut back or eliminate caffeinated drinks, and see how that might be affecting you. 
4. If you are just rubbing shampoo into your hair and rinsing out a minute later, you are washing your hair wrong.
  • After you've gotten your hair good and wet from the showerhead, use a quarter-sized amount of shampoo, rub it between your palms and, starting at the roots, work it into your hair. Now, before you go any further, give your scalp a good 2-3 minute massage (out of the water flow) with your hands. Work the shampoo into and around your scalp, which will really get the dirt, oils and styling products out; without the massage, you are just rinsing shampoo over them. You can add water every 30 seconds if you need it. Then work the lather down the rest of your hair if it's long (you can add more shampoo now if you need to) and treat it gently — sort of pat and squeeze your hair — to keep damage from occurring and frizzing from popping out. 
5. If your bra straps constantly fall off your shoulders, the center of your bra doesn't rest against your sternum, or your boobs overflow your cups on the top, it's because you're wearing the wrong bra size. Cup overflow means you need to go up a cup size (or even two or three); if the center of the bra isn't flat, go up a cup size; straps sliding down your shoulders mean you need to go down a band size. How to get it right?
  • Do some measuring to see where you are by the charts (and check out this video), but then try on at least 10 bras in your size range.
  • A really important consideration is also bra shape or style; a balconnet or demi bra is best for women with smaller cup sizes and women with straight (not sloping) shoulders; and plunge bras aren't really built for women with smaller busts. Taking the time to determine which bra styles work for you is as important as finding the right size. 
 Lifehacks for better health, because we all get it wrong sometimes!

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Starre Vartan ( @ecochickie ) covers conscious consumption, health and science as she travels the world exploring new cultures and ideas.

Lifehacks for 5 personal habits that you're probably doing wrong
There are smarter and better ways to maintain — and even improve — your health.