An estimated 50 percent of American adults use nutritional supplements regularly. But some doctors suggest that half of these adults aren't using these nutritional supplements correctly.

So, how exactly is it possible to use nutritional supplements incorrectly? Well, incorrect nutritional supplement use starts with a lack of understanding of these types of supplements. Too many people make the mistake of looking for bargain prices when they look for nutritional supplements. The cheapest is rarely the best when it comes to nutritional supplements.

People looking to add nutritional supplements to their already fairly healthy diets should take the time and do some background research. Don't buy low-quality nutritional supplements with little or no research behind them. And, unfortunately, a large percentage of the useless nutritional supplements are those that put all their money into advertising instead of quality ingredients. These are the types of nutritional supplements that are promoted as "popular" and often seem to be forever on sale.

When choosing a nutritional supplement, it's always better to choose a caplet over a tablet. The simple reason for this is that your body usually can't effectively dissolve a tablet nutritional supplement. And if your body can't dissolve this type of nutritional supplement, then it won't be able to breakdown the ingredients and feed the nutrients to different parts of your body. Plus, the super low-quality nutritional supplements rarely dissolve at all. Studies of these types of nutritional supplements show that the entire whole form of the tablet can sit in your stomach like a tiny stone for many, many hours. So always select a capsule nutritional supplement. It's much nicer to your digestive system and much better for you body.

Avoid single-nutrient nutritional supplements. Single-nutrient foods don't exist, so why would you feed your body single-nutrient nutritional supplements? Eating these types of nutritional supplements will only succeed in ruining the balance of your body's chemicals.

And don't try a "piecemeal" approach to nutritional supplement use. A piecemeal approach is when you select a variety of single- or multiple-nutrient nutritional supplements, and mix-and-match them to try and make up for where you think your diet lacks. Few people have the skills to do this type of nutritional supplement maneuvering.

When selecting nutritional supplements look for ones that say they are "laboratory tested." Laboratory tested nutritional supplements means that they've been created by responsible manufacturers who choose to follow the FDA regulations, even though they're not required to do so.

Pick nutritional supplements that are "quality guaranteed." Quality guaranteed nutritional supplements are ones that use pharmaceutical-grade products.

Be wary of nutritional supplements that claim to be 100 percent natural. A 100 percent natural nutritional supplement, just like 100 percent cobra venom, is probably not good for you. And always make sure every nutritional supplement container you buy has an expiry date. Nothing stays good forever, not even nutritional supplements.