Water in itself has no nutritioned value. Yet it is perhaps the most important of all food components. Why? A major reasons is that water is the medium both for transporting nutrients to the cells of the body and for removing cellular waste products. In addition, water acts as a medium for digestion, is the body’s temperature regulator, serves to cushion vital organs, and lubricates the joints. Finally, water and some of the chemicals it carries are responsible for bodily structure. The cells in our bodies contain fluid, and there is fluid around the cells too. As much as 80 percent of the body weight may be water, although the average is closer to 60 percent.
How much water do you need each day?
While the body can survive for long periods without food, it can exist for only a few days without water. An average of two and a half litters of water (slightly more than two quarts) per day is the recommended daily intake. Of course, not all of this need be consumed as plain water; other liquids serve as well. Generally speaking, only about 50% of the body’s water requirement comes directly from liquids, another 25 and 50 percent is from food, and the rest is an end product of metabolism.
The actual amount of water out bodies requires each day depend on our environment, our physical activity, the season of the year, and the type of food we eat.
Fiber, also known as “roughage” or “bulk,” is another non-nutritive substance that is necessary in the human diet. Fiber consists of indigestible carbohydrates, largely the cellulose that is part of the fruits, vegetables and grains we eat (common example of fiber are fruit skins and wheat bran.). Today, scientists are calling attention to the importance of fiber in the diet-largely because modern American diets may be deficiency in it. Our diets nowdays consist predominantly of processed foods. In them, most fibers has been either milled or peeled away (white bread, white rice, French fries, instant potatoes), and so many traditional sources of fiber have disappeared from the diet.
Fiber is necessary in the digestive process. In the large intestine (the colon), it serve to bind other waste products with large amounts of water, forming an easily passed, soft, large stool. Adequate amounts of fiber in the diet result in stools that are increased in both volume and frequency. This, in turn, helps to prevent diverticulitis, a physiological problem in which the large intestinal wall weakens and balloons out. The presence of fiber also provides a medium for the growth of certain bacteria that help the body synthesized nutrients such as vitamin K.