Health and fitness fads come and go—wheatgrass shots, waist trainers, weight-loss pills, and gluten-free diets (unless, of course, you're actually gluten-intolerant). Some fads are more persistent, such as juice cleanses and spinning classes. And in our increasingly health-centered world, it can be hard to distinguish between what's actually healthy and what isn't.

So what current health and fitness gadgets don't live up to the hype?

Shake Weights

The hype: Simply by holding an electric weight that vibrates in your hand for merely six minutes a day, you'll be able to tone your arms in just a few weeks.

The truth: Nothing beats an actual workout. While holding a shaking weight beats lying on the couch eating cheese puffs, if you're hoping to see dramatic results, you're going to be disappointed.

Weight-loss teas

The hype: Drink a mystical mix of herbs and powders and you can speed your metabolism, cure your headaches, lose those extra ten pounds, and/or get glowing, perfect skin.

The truth: While some herbs and teas can support things like headache relief and healthy skin and hair, there is no miracle potion that will cure all that ails you. Anything labeled "detoxing" is just a marketing scheme—your liver and kidneys do all the detoxing your body needs, and no amount of tea or powder is going to do a better job than them.  

Sauna suits

The hype: Wearing a skin-tight layer of plastic (a "plastic suit." if you will) that will supposedly help you burn more calories and drop water weight and therefore lose weight faster. It's also been promoted by the likes of Kim Kardashian.  

The truth: While sweating enough to fill buckets certainly will help you lose water weight, this weight loss isn't something that can be sustained—right when you replenish your fluids, you'll replenish your weight. These suits can even be dangerous, as you run the risk of overheating or becoming dehydrated.    

Himalayan salt lamps

The hype: Tame allergies, cure Seasonal Affective Disorder (SAD), boost your mood, and sleep easier, all with the help of these aesthetically pleasing lamps.

The truth: There is no definitive proof that these salt rocks can do as they claim. Dr. Svetlana Kogan of New York City, who specializes in holistic and integrative medicine, said that, "The talk has been that the negative ions supposedly produced by the lamps help to neutralize the positive charge. But to be honest with you... I haven't seen any large studies that would confirm this." If you'd like a pretty decoration, you should invest in one of these lamps—just don't expect it to cure your asthma at the same time.

While being healthy is incredibly important, it's just as essential to do your research before you invest in any new fads. Talk with your doctor before starting a new diet or exercise programs, and remember—just because something made the news, it doesn't mean it's safe or effective for everyone.