We humans, like all other forms of life, are made of cells. Though all of your cells have the same DNA, they are not all the same. There are hundreds of different types of cells, and each cell type has its own very specific and important role that it plays in keeping you alive and in good health. Cells have the same complexity found in large cities. Think of the complexity of New York, Tokyo, Paris, Buenos Aires, Mumbai, Los Angeles, Mexico City, Taipei, or Guangzhou, and you will have a good idea of how complicated any one cell is. Now, realize that you are made of trillions of these cells (thats 1000000000000s) and here we now begin to describe the complexity of the human body. Whenever we here some generalization about such-and-such being good for you or such-and-such being bad for you, we must recognize that except for obvious trauma (severe wounds and radiation exposure for instance) most of what we eat may be good for some cells and bad for others. The difficulty is, with the great diversity of cells, and substances that we can introduce our bodies to, it is nearly impossible to evaluate the full effects of any substance on all of our body's cells to determine if the effects are positive or not. Thus we are given generalizations because we simply do not know the full details yet. Just know that any of you are amazing, incredibly complex beings. You are a Planet of cities each with your own natural wonders.