THE COMPLEXITY OF NUTRITION ON CANCER

Most people outside science think that nutrition is simply a matter of what you eat and that what is important is that you get enough in the way of the basic food groups and calories. In fact, nutrition is much more complex than that. First, we have to understand the purpose of eating. It is not to satisfy our taste buds or to keep our stomachs from growling from hunger, even though many in the industrialized world think this way. Second, we have to understand that the body is a collection of immensely complex chemical reactions-tens of thousands of them.

Our cells and tissues are not simple cellular organisms living together in harmony. They are extremely complex biochemical laboratories engaging in tens of thousands of biochemical reactions every second of our lives. These chemical. reactions require special types of substances that must be supplied to our cells for them to function normally. Fortunately, our bodies can adapt to many deficiencies in these chemicals and can even make substitutions. Yet, these deficiencies can cause the cells to work less efficiently, making them highly susceptible to diseases, including cancer.

The nutritional requirements for cells also vary widely, with some cells requiring more of a particular nutrient than other cells. This is because the cells have different functions. For ex ample, the thyroid gland needs a different set of chemicals than does breast tissue.
We have also learned that the distribution of vitamins and their breakdown products varies considerably from tissue to tissue. For example, the female cervix concentrates more vita min C and folate than does the gallbladder. This should mean that a deficiency in vitamin C and folate will increase a woman's risk of cervical cancer, and that is exactly what we sec. Women with very low vitamin C intake can have a cervical cancer risk ten times higher than women who consume more dietary vitamin C.

In some instances, a tissue may require a lot more of a par ticular nutrient than normal, as for instance in the case of cervical cancer where even normal blood levels of folate are insufficient to prevent the disease. It takes higher intakes of folate to prevent cervical cancer in women at high risk. This is one of the reasons why the recommendations for the vitamins and minerals are constantly being revised upward.

Sometimes a person can be eating a perfectly healthy diet, with lots of fruits and vegetables, low amounts of harmful fats, and little sugar, and still have a high risk of cancer. One reason for this is that unless the nutrients can enter the bloodstream, they do little good. We call this inability to enter the bloodstream malabsorption. Occasionally, malabsorption involves only a single type of nutrient or even a single vitamin or mineral. So how can we know if we are absorbing our nutrients properly? One way is to have our blood levels of the nutrients measured directly. Several laboratories measure vitamin and mineral blood levels. Yet, even then we may be fooled. Many vitamins are converted from the form found in food into an especially active form required by the cells in the body. For example, the riboflavin from food is converted into riboflavin-S-phosphate in the body, and the pyridoxine (vitamin B6) from food is converted into pyrodoxal-S-phosphate in the body. The conversion processes for these vitamins require special enzymes, which are often impaired in the elderly, in people undergoing cancer treatments, and in people suffering from a chronic disease.