CLEARING UP SOME CONFUSION
The distinction between fat and oil in popular terminology is primarily one of convenience, and refers simply to whether a fat is solid at room temperature (known as a FAT) or liquid at room temperature (known as an OIL). Both are considered to be FAT by dieticians and nutritionists. Nutrition labels on foods include them together under "fats" and make no distinction unless they list saturated and unsaturated fats as subcategories under fats. Some labels also include polyunsaturated and monounsaturated subcategories - which is a real help when trying to eat healthfully.
TYPES OF FATS
Saturated
Fats are either saturated or unsaturated. Saturated fats include what we usually call "fat" in common terminology (solid at room temperature, such as butter). It is called "saturated" because the chain of carbon molecules has no places or spaces for another atom (in particular, a hydrogen atom) or molecule to attach to it. It is more or less "filled up" (saturated with hydrogen). Beef and pork contain high levels of saturated fat.
The main cardiovascular concern about animal fat has to do with eating it IN COMBINATION with cholesterol (which is found in all animals, including humans -- because it is a necessary building block for many bodily structures -- for instance, sex hormones). Beef has received a lot of bad press over the past few decades as something to avoid because of its cholesterol levels. The cholesterol in beef becomes problematic because of the high levels of saturated fat that are also in beef.
Chicken, however, actually contains more cholesterol than beef, but because its levels of saturated fat are much lower, the cholesterol in chicken does not cause as much of a rise in actual blood cholesterol. The most very recent evidence, however, points to transfatty acids (see #7 below) as being worse (MUCH worse) than saturated fat in causing cholesterol buildup. (Some researchers even suggest that transfatty acids and NOT saturated fats are REAL culprits.)
It appears that because of its molecular structure, transfatty acids damage the lining of the blood vessels. When the body then sends agents to repair the damaged blood vessels, the cholesterol passing through the vessels "stick" to the repair agent, causing a buildup of cholesterol and thus blocking the vessel. Consider this in light of the fact that Americans have greatly cut back on their consumption of animal fat in the past 80 years (from 83% to 53%) while increasing their consumption of transfatty acids (from 17% in 1910 to 47% in 1990), during which time both cardiovascular diseases and cancer have dramatically increased. (Transfatty acids also seem to be indicated in immune system suppression.)
While these statistics are not necessarily conclusive, the upshot of all this is: while consuming large quantities of saturated fat is not particularly healthy for a variety of other reasons, many people have been avoiding the WRONG kinds of fats in an attempt to stay heart-healthy.
Unsaturated
Unsaturated fats include what we usually call "oil" in common terminology. There are two *very important* categories of unsaturated fat -- polyunsaturated and monounsaturated.
Polyunsaturated Fats
In contrast to saturated fats, there are LOTS (poly = many) places in a polyunsaturated fat where a hydrogen molecule COULD be attached and instead two carbon atoms in the carbon chain make a double bond with each other. This extra carbon bond uses up a possible "place" for a hydrogen atom to attach on the molecule and prevents it from holding as much hydrogen as it is possible to hold. Consequently it is NOT saturated (not saturated = UNsaturated) with hydrogen.
Some very important fats -- critical for good health -- (omega 3 and omega 6) are polyunsaturated. Omega 3's are found primarily in fish. Omega 6's are found primarily in lean meats, soy foods, oats, and nuts and seeds. Borage and evening primrose oils are alternative sources for omega 6 oils and are usually consumed in capsule form as a dietary supplement. Or you can just eat oatmeal for breakfast. In some very recent studies, these linoleic acid-rich oils have been found to be more protective against heart disease than even the monounsaturated oils.
Continued on Page 3