The more modified a food is, the more certain features of its nutrients may have changed, either making them harder to absorb or even changing their cellular structure and therefore their use in the body. In this case, at what point does a nutrient cease to be a nutrient? The answer isn't clear, but encourages us to ask the question, "Am I getting real nutrients from this food, or am I getting pseudo-nutrients?"

Also important is the topic of synthetic nutrients. These are manmade nutrients that -- chemically speaking -- aren't precisely the same as natural nutrients. The synthetic form of vitamin E, for instance, isn't as active as the natural forms, and there are those who suggest that it doesn't at all act like natural vitamin E does in the body (which works to prevent cancer, assist the circulatory system, and help to prevent heart disease, for instance). If that's the case, you may think you're getting plenty of vitamin E when -- because you're getting the synthetic variety you're really getting none at all -- you are in danger of deficiency symptoms.

As a result, when choosing foods, the more you can choose that are still in their natural state, the better. Likewise, the less processing a supplement goes through (the closer it remains to a whole food), the more likely it is to provide you with really usable nutrients.