About Omega-3 Fatty Acids

The can make most of the fatty acids it needs from the carbon, hydrogen, and oxygen atoms provided by food. These are called nonessential fatty acids because it is not essential for us to consume them in the foods we eat.

However, there are polyunsaturated fatty acids that the body cannot manufacture, and these are called the essential fatty acids. They are necessary for good health, but we can only get them from food. There are two main groups of essential fatty acids: the omega-3 oils and omega-6 oil. The numbers "3" and "6" refer to the place where the first kink in the carbon chain occurs. Linoleic acid is the primary member of the omega-6 family, which the body can convert into longer-chain arachidonic acid (ARA). Likewise, alpha linolenic acid (ALA) is the primary omega-3, which the body can convert into eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Long-chain omega-3 and omega-6 fats form the membranes of every cell in the body, and influence every process in the cell.

The difference between the two groups is that the omega-3 oils are more polyunsaturated than the omega-6s. That is, the omega-3s have fewer hydrogen atoms - and consequently, more kinks - in their molecules. This means that the omega-3 oils are much more liquid that the omega-6 oils at a given temperature.

Functions of the Omega Fatty Acids

Why are the omega fatty acids so important to health? There are number of reasons. Because they form important components of cell membranes, omega oils are needed to prevent drying and flaking of the skin. They are also needed to ensure proper growth and development in infants and children. But two of the omega oils' most important functions involve regulating the body's use of cholesterol, and the production of substances that regulate nearly all other bodily processes.

The Omega-Cholesterol Connection

Many people think of cholestrol as being a health villain, but actually, it serves a lot of information functions within the body. Cholesterol forms a major part of the membranes that enclose every cell. As part of the cell membranes within the skin, cholestrol is changed by sunlight into vitamin D, which regulates the body's use of calcium. It is converted in the liver into bile acids, which are needed for fat digestion. It is important for proper nerve function. It is used to create sex hormones - the chemicals that control sexual functioning. It is also used to create other hormones, such as cortisone, that control other bodily functions.

Cholestrol doesn't dissolve in water, which means it can't move through the bloodstream by itself. Therefore, the liver combines each cholesterol molecule with a long-chained essential fatty acid, and then surrounds it with protein. The resulting package, called a lipoprotein, is capable of moving through the bloodstream.

Low-density lipoprotein (LDL) carries cholesterol throughout the body for use by the body's cells. If LDL levels in the blood become too high, or if the LDLs become rancid, the cholesterol tends to stick to the walls of the arteries, which causes the arteries to become narrower. That’s why LDL has been called the “bad” cholesterol. On the other hand, high-density lipoprotein (HDL) has been called “good” cholesterol because it removes cholesterol from the blood and carries it back to the liver. Only when the diet provides enough essential fatty acids to link up with cholesterol in the liver can cholesterol do its many jobs safely.

In contrast with saturated fats, which have a tendency to increase blood-cholesterol levels, unsaturated fats lower blood cholesterol. A blood-cholesterol level – one above 240 milligrams of cholesterol per deciliter of blood (units of cholesterol) – is considered to be a risk factor for heart disease.

Major medical emphasis has been placed on lowering cholesterol levels vigorously by means of drugs and diet. However, important large-scale studies have been done of people with high levels of blood cholesterol, and the results of these studies have been disconcerting. They show that lowering cholesterol does indeed reduce the number of deaths from heart disease over a period of years, but does not in the least improve overall mortality rates. People who achieved the lowest cholesterol levels - 160 units or less – has unexpectedly high rates of death from other causes, such as liver cancer, stroke, lung disease, alcoholism, and suicide, when compared with those who had normal or high cholesterol levels.

Why would low cholesterol levels be correlated with so many serious problems? Some scientists say that very low cholesterol levels interfere with the production of crucial cell products that require cholesterol. In light of cholesterol’s fundamental, nonvillainous role in the body, lowering your cholesterol level should not be the major goal. Rather, the emphasis should be on measure – dietary measures among them – that improve overall health and as an added benefit, produce optimal cholesterol levels.

One of the dietary measures you can take is to increase the amount of omega-3 fatty acids you consume by eating seafood or taking fish oil supplements. Omega-3 oils appear to change the balance of cholesterol in the blood – they lower the level of “bad” LDLs and raise the level of “good” HDLs.

Omega Oils and the Body’s Regulators

The body also uses the omega oils to create a variety of chemicals, called eicosanoids that regulate a wide variety of bodily processes. The omega-3 and the omega-6 families each produce their own eicosanoids. The important role these chemicals play within the body helps to explain why the essential fatty acids are so essential.

One of the most important groups of eicosanoids is the prostaglandins. Medical interest in prostaglandins – extremely active biological substances made only from essential fatty acids – has grown. Prostaglandins are so vital to human life that, in 1982, the Nobel Price in medicine went to three scientists who had studied more than a dozen prostaglandins.

Prostaglandins operate in most tissues of the body to regulate just about every bodily function, including:

The list seems endless – and it may be. Scientists are still discovering regulator effects of the prostaglandins.

Prostaglandins constitute a local tissue hormone like system. They work with hormones, such as insulin, that are released directly into the bloodstream and act widely throughout the body. The prostaglandins translate the directives of hormones into local instructions for local cells and tissues. In this way, prostaglandins implement hormone function on the local level, in addition to carrying out other regulatory activities.

The omega-6 and omega-3 fatty acid groups each produce distinct prostaglandins with different functions. For good health, both types of fatty acids are needed, and in the right ratio. That vital balance is hard to achieve because omega-3 is often missing from the modern diet. When optimal amounts of essential fatty acids are added to the diet, many of the body’s organs – including the skin, heart, kidney, liver, and reproductive organs – function better, and the body’s ability to fight both cancer and infections is improved.

Prostaglandin imbalances can also lead to loss of the body’s ability to protect itself. For example, certain prostaglandins in the stomach govern the secretion of a protective stomach coating that prevents digestive acids from acting on the walls of the stomach. Without this coating, the stomach would digest itself. People may be more susceptible to stomach ailments when prostaglandin imbalances cause this safeguard to fail. Such imbalances are also believed to be responsible for similar safeguard failures in other parts of the digestive system.

Supplements of omega-3 fish oil can often help the body right prostaglandin imbalances. This has been supported in numerous studies for various ailments.

Omega Oils in Balance

Given the extensive regulatory role of the essential fatty acids, we can begin to see why dietary disruption of these fatty acids can disrupt just about any function and produce almost any disease, depending on each individual’s susceptibility to specific imbalances. It has also been shown that there’s a positive nutritional relationship between omega-3 fatty acids and the amounts of fiber, selenium, and other health-promoting substances in the diet, as well as negative effects from the intake of saturated fat, trans-fatty acids, and sugar.

I must stress that the omega-6 oils are not inherently “bad” oils; they are vital to human health. Rather, the problem is one of balance. Scientists speculate that our prehistoric ancestors probably ate roughly equal amounts of omega-6 and omega-3 essential fatty acids. Today, most people in the industrialized world eat diets with omega-6 to omega-3 ratios of 10-to-1 or even 30-to-1. Because of evidence that a disproportionately high intake of omega-6 fats may be a factor in increased cancer, even conservative scientists are now suggesting that we reduce the omega-6 fats and increase the omega-3 fats in our diet.