WHAT SCIENCE STILL DOES NOT KNOW ABOUT FOODS? SPECIAL DIETS

SPECIAL DIETS 

Special diets can be of value for certain specific health problems. For example, a protein-free diet may be prescribed in some cases of severe kidney damage; a high-protein diet in some cases of hepatitis; a high- residue diet in cases of atonic constipation; a low-fat diet in certain diseases of the liver and gallbladder; a low-purine diet in gout; a low- sodium diet in high blood pressure, congestive heart failure, and toxemia of pregnancy; a bland diet for ulcer, gastritis, and hiatus hernia; a gluten- free diet for celiac disease and cure. 

Special dietary treatment is also an important part of the overall therapy in many cases of diabetes. Whenever a special diet may be of value, it should, of course, be prescribed by a physician on the basis of the patient's individual needs.

WHAT SCIENCE STILL DOES NOT KNOW ABOUT FOODS 

Every physician and scientist concerned with nutrition knows well that despite all that has been learned, much more remains to be. At any time, some fundamental new finding-of a previously unknown vitamin or other essential nutrient-may be made. 

At the risk of being repetitious, we would like to emphasize again that every advance to date has underscored the one fact: except in special instances, the best and healthiest diet is a balanced and generously varied diet. Nature distributes her largesse. We can be most certain of benefitting from it by making use of many rather than limited numbers of foodstuffs. Almost certainly, if we do this, we will be enjoying the values of still-undiscovered vital elements.

WEIGHT CONTROL 

WHILE THERE are nutritional diseases due to deprivation-rickets, scurvy, and others-by far the most common nutritional disease in this country is one that results from abundance. Overweight, affecting one in every five Americans, is a mammoth, chronic, frustrating problem. 

It can be called, justly, the number-one health hazard of our time. It's a remediable problem-but not, unfortunately, the way most of us choose to go about attacking it. To a much lesser extent, underweight constitutes a health problem. And the correction of both is an important function of preventive medicine. 

WHAT CHOLESTEROL DOES ON OUR BODY? IS THERE GOOD CHOLESTROL

ABOUT CHOLESTEROL

Cholesterol has become a household word because of evidence indicating that excesses of it in the blood may play a part in producing coronary atherosclerosis, the narrowing of the coronary arteries which may lead to heart attacks. Cholesterol is present as such in some foods. It is also produced by the body. Actually, the soft, waxy, yellowish substance is an essential part of every body cell. It plays a basic role in the passage of substances through cell walls. 

One example of how cholesterol does this is readily observable: when you put your hand into a basin of water, little of the water soaks into the skin. The reason: cholesterol in the outer layer of skin cells makes the skin impermeable to water.

Since the material is essential, the body is equipped to produce a supply as well as use what comes in, ready-built, in food. The liver can make cholesterol from molecules of acetyl coenzyme A, a chemical derived from fats, carbohydrates, and proteins. It is not cholesterol per se but an excess of it in the blood which is the danger factor. 

And while an excess can be traced to some extent to a diet heavy in foods rich in cholesterol, a high-fat diet may raise blood cholesterol levels abnormally. This appears to be due to increased deposits of fat in the liver, providing an increased source of acetyl coenzyme A for liver manufacture of cholesterol.

Moreover, it is the nature of the fat in the diet that is significant. Some types of fat, known as saturated, increase blood cholesterol levels. Others, called unsaturated and polyunsaturated, do not-and, in fact, tend to slightly decrease cholesterol levels. The difference between saturated and unsaturated, from a chemist's viewpoint, is a matter of hydro-gen atoms: saturated fats are saturated with, or full of, hydrogen atoms; unsaturated fats have room for more hydrogen atoms. 

In everyday terms, the primary saturated fats are milk fat, meat fat, coconut oil, and cocoa fat.

 Milk fat includes the fat in butter, most cheeses, and ice cream as well as whole milk. Meat fat means primarily the fat of beef, pork, and lamb; veal has less fat, and chicken and turkey are low in fat and the fat they contain is less saturated. Polyunsaturated fats are the liquid vegetable oils such as safflower, soybean, corn, and cottonseed, the Food You Eat.