Is margarine bad for you? Are hydrogenated fats in margarine harmful? Is butter better? These are all important questions. News stories based on recent research studies have seriously confused the issue. Should we be concerned about hydrogenated fats as occur in many commercial margarines, referred to as "trans-fatty acids"?
The problem is more complex than just saying "hydrogenated" fats, because there are many different margarines, made with many different fatty acids. Hydrogenation of one fatty acid does not produce the same effect as hydrogenationh of other fatty acids.
What does hydrogenation mean? It is related to the division of fatty acids into saturated, monounsaturated, polyunsaturated and highly polyunsaturated fatty acids. Fatty acids are attached to glycerol to form fat, whether it is in your body or in your food. Triglycerides measured in your bloodstream are simply three fatty acids attached to glycerol (glycerine).
A saturated fatty acid is a long carbon chain and each spot on the chain that can hold a hydrogen atom has one. There is no room to attach more hydrogen atoms so it is saturated.
Unsaturated fatty acids have at least one area where two adjacent carbon atoms are not attached to the hydrogen atoms- "there is an empty seat on the bus." When one pair of seats is empty, it is a monounsaturated fatty acid. If two or more pairs are empty, it is a polyunsaturated fatty acid. Some fatty acids, particularly those found in cold-water fish oil, may have five or six pairs of empty seats on the bus, and these are now designated as highly polyunsaturated fatty acids.
Hydrogenation simply means filling one or more empty seats on the bus. If you did this to a monounsaturated fatty acid, you would convert it to a saturated fatty acid. That is considered bad if you want to limit your saturated fat intake. But if you add hydrogen to only one pair of carbon atoms in a polyunsaturated fat, you still have an empty pair of seats on the bus and it is a monounsaturated fatty acid, not a saturated fatty acid. That can happen when soybean oil is hydrogenated.
It is misleading to state that hydrogenating unsaturated fatty acids convert them to saturated fatty acids. It depends entirely on which unsaturated fatty acids are hydrogenated. In terms of margarine that means partially hydrogenated fatty acids in some oils used in making margarine will be decidedly different from margarines made using different fatty acids - for example, whether the margarine was made with hydrogenated corn oil or soybean oil and how much was converted.
Obviously, you could hydrogenate one spot on a highly polyunsaturated fatty acid and it would still be a polyunsaturated fatty acid. The glib general statement that hydrogenating oils used to make margarine is bad for you lacks specificity.
SOLID FACTS
Why would food companies want to hydrogenate unsaturated fatty acids? In the case of margarine, converting some of the unsaturated fatty acids to hydrogenated fatty acids makes it solid instead of liquid. It is possible to spread the margarine on bread. The Italians solve this problem by dipping bread into olive oil or pouring a bit of olive oil on their bread. The olive oil is seasoned to taste.
You have probably also read that unsaturated fats are liquid and saturated fats are solid. That is not true at all. While hydrogenating unsaturated fatty acids can be done to make a fat, as in margarine, more solid, the most highly saturated fatty acids - and the worst in terms of causing adverse changes in fatty-cholesterol levels-are liquid. Coconut oil is the prime example and not far behind are palm kernel oil and palm oil. These tropical oils must be avoided if you want to limit your saturated fat intake.
On the other hand, most animal fat is solid, even if it contains a significant amount of unsaturated fat. Chicken fat, which is solid, is only 31% saturated fat. The rest is all unsaturated fat. Pork fat - lard- is 41% saturated fat while beef tallow is 52% saturated fatty acids. If you are interested in limiting your saturated fat intake, your order of preference would be chicken, and beef. However, the amount of total fat of all kinds, and associated calories, are also a consideration.
It is not true that there are no advantages in using poultry versus beef if you want to be on a low-saturated fat diet, as many have been led to believe by some published statements. It is true that there is very little difference in the cholesterol content of the beef, poultry and pork. A skinned chicken breast is very low in fat of any kind, and provides even less saturated fat.
The amount of saturated fat in a food item is often more important than its cholesterol content. Some of the statements comparing poultry to beef are reminiscent of the claim by tropical oils that they contain "no cholesterol". That is true since cholesterol occurs only in animal products, but such products as coconut oil will stimulate your body to produce an excess amount of cholesterol.
TRANSITORY CHANGES
Many research studies reported by the news media on the effects of fat in the diet are not applicable to the health of the majority of the general public that needs to know how to control abnormal fatty-cholesterol levels. It takes a minimum of six months on a new diet to be certain what its effects really on a transitory change, not necessarily a permanent change.
It is true that when many people lose weight, their total cholesterol will go down, but as they maintain their diet and stabilize their weight, the cholesterol may start to rise again. The body has learned to adapt to the new situation and produce the previously high levels of cholesterol. Nevertheless, short-term studies are constantly reported, and then, without critical analysis, duly reported on the evening news.
Other studies on cholesterol levels are done in perfectly healthy, young individuals who have quite normal cholesterol levels to begin with. Diets in these individuals will not reveal the affects that occur in a person who has abnormal cholesterol levels, such as a high total cholesterol level or a low HDL level. They are essentially meaningless in deciding what a person with such health problems needs to do.
It is analogous to putting a person with normal blood glucose levels on a diabetic diet and not seeing any effect, while in a diabetic, the limitation of sugars, sweets and weight reduction can have significant effects. These are some of the reasons for the confusion, both in the research community and in the news media regarding what is good and what is bad fat.
WHAT YOU CAN DO
Some generalizations can safely be made and serve as guidelines as to what you can and should do. First, find out if you have any reason to need to be concerned about your cholesterol levels, blood pressure, blood glucose or having excess weight. Diets are intended to correct problems.
1. If you have no health problems, it is best to follow a well-balanced mixed diet and enjoy yourself. Eat well and stay in shape. What needs to be done should be determined on an individual basis related to your personal health status, such as your cholesterol levels and blood pressure levels.
2. If you have a need to be concerned about the fat in your diet, then pay attention to the known facts. To lose bodyfat, limit fat intake of all types because all fats are high in calories. It doesn't matter whether it is saturated or unsaturated, you will need to limit your fat intake. You should limit some carbohydrates too, such as sweets and starches.
3. If you need to limit saturated fat, limit your butter fat intake. You are better off to subtitute margarine because most commercially available brands are far better in terms of the body's response to cholesterol production than butter. Butterfat is 66% saturated fat. That doesn't meant the tub and stick margarines are outstanding choices, but they are not as bad as butter in these terms. They are also cholesterol free.
4. Do use one of the cooking oils for food preparation, such as corn oil, canola oil, soybean oil, safflower oil or olive oil - oils low in saturated fat. If you want to take a page from the Italians, you may learn to dip your bread in olive oil or spread olive oil, seasoned to taste, on it. Or you could use another low saturated fat oil of your choice. Remember the calories, though.
5. When thinking of individual foods, remember that the entire diet, not specific items, must be considered. In most instances, using a suitable margarine for some things while using unsaturated oils for the rest of food preparation will meet the requirements to limit saturated fat intake. Liquid margarines in squeeze bottles contain less hydrogenated fatty acids than tub or stick margarine.
6. The next step is to see how such diet modifications work in your individual situation on a long-term basis, not just six weeks. If the diet changes are not adequate, further changes may be needed, more exercise may be required or you may need one of the medicines needed to improve blood cholesterol levels. What counts is what happens in your case, remember everybody diet is different. Individualize, don't generalize.
The problem is more complex than just saying "hydrogenated" fats, because there are many different margarines, made with many different fatty acids. Hydrogenation of one fatty acid does not produce the same effect as hydrogenationh of other fatty acids.
What does hydrogenation mean? It is related to the division of fatty acids into saturated, monounsaturated, polyunsaturated and highly polyunsaturated fatty acids. Fatty acids are attached to glycerol to form fat, whether it is in your body or in your food. Triglycerides measured in your bloodstream are simply three fatty acids attached to glycerol (glycerine).
A saturated fatty acid is a long carbon chain and each spot on the chain that can hold a hydrogen atom has one. There is no room to attach more hydrogen atoms so it is saturated.
Unsaturated fatty acids have at least one area where two adjacent carbon atoms are not attached to the hydrogen atoms- "there is an empty seat on the bus." When one pair of seats is empty, it is a monounsaturated fatty acid. If two or more pairs are empty, it is a polyunsaturated fatty acid. Some fatty acids, particularly those found in cold-water fish oil, may have five or six pairs of empty seats on the bus, and these are now designated as highly polyunsaturated fatty acids.
Hydrogenation simply means filling one or more empty seats on the bus. If you did this to a monounsaturated fatty acid, you would convert it to a saturated fatty acid. That is considered bad if you want to limit your saturated fat intake. But if you add hydrogen to only one pair of carbon atoms in a polyunsaturated fat, you still have an empty pair of seats on the bus and it is a monounsaturated fatty acid, not a saturated fatty acid. That can happen when soybean oil is hydrogenated.
It is misleading to state that hydrogenating unsaturated fatty acids convert them to saturated fatty acids. It depends entirely on which unsaturated fatty acids are hydrogenated. In terms of margarine that means partially hydrogenated fatty acids in some oils used in making margarine will be decidedly different from margarines made using different fatty acids - for example, whether the margarine was made with hydrogenated corn oil or soybean oil and how much was converted.
Obviously, you could hydrogenate one spot on a highly polyunsaturated fatty acid and it would still be a polyunsaturated fatty acid. The glib general statement that hydrogenating oils used to make margarine is bad for you lacks specificity.
SOLID FACTS
Why would food companies want to hydrogenate unsaturated fatty acids? In the case of margarine, converting some of the unsaturated fatty acids to hydrogenated fatty acids makes it solid instead of liquid. It is possible to spread the margarine on bread. The Italians solve this problem by dipping bread into olive oil or pouring a bit of olive oil on their bread. The olive oil is seasoned to taste.
You have probably also read that unsaturated fats are liquid and saturated fats are solid. That is not true at all. While hydrogenating unsaturated fatty acids can be done to make a fat, as in margarine, more solid, the most highly saturated fatty acids - and the worst in terms of causing adverse changes in fatty-cholesterol levels-are liquid. Coconut oil is the prime example and not far behind are palm kernel oil and palm oil. These tropical oils must be avoided if you want to limit your saturated fat intake.
On the other hand, most animal fat is solid, even if it contains a significant amount of unsaturated fat. Chicken fat, which is solid, is only 31% saturated fat. The rest is all unsaturated fat. Pork fat - lard- is 41% saturated fat while beef tallow is 52% saturated fatty acids. If you are interested in limiting your saturated fat intake, your order of preference would be chicken, and beef. However, the amount of total fat of all kinds, and associated calories, are also a consideration.
It is not true that there are no advantages in using poultry versus beef if you want to be on a low-saturated fat diet, as many have been led to believe by some published statements. It is true that there is very little difference in the cholesterol content of the beef, poultry and pork. A skinned chicken breast is very low in fat of any kind, and provides even less saturated fat.
The amount of saturated fat in a food item is often more important than its cholesterol content. Some of the statements comparing poultry to beef are reminiscent of the claim by tropical oils that they contain "no cholesterol". That is true since cholesterol occurs only in animal products, but such products as coconut oil will stimulate your body to produce an excess amount of cholesterol.
TRANSITORY CHANGES
Many research studies reported by the news media on the effects of fat in the diet are not applicable to the health of the majority of the general public that needs to know how to control abnormal fatty-cholesterol levels. It takes a minimum of six months on a new diet to be certain what its effects really on a transitory change, not necessarily a permanent change.
It is true that when many people lose weight, their total cholesterol will go down, but as they maintain their diet and stabilize their weight, the cholesterol may start to rise again. The body has learned to adapt to the new situation and produce the previously high levels of cholesterol. Nevertheless, short-term studies are constantly reported, and then, without critical analysis, duly reported on the evening news.
Other studies on cholesterol levels are done in perfectly healthy, young individuals who have quite normal cholesterol levels to begin with. Diets in these individuals will not reveal the affects that occur in a person who has abnormal cholesterol levels, such as a high total cholesterol level or a low HDL level. They are essentially meaningless in deciding what a person with such health problems needs to do.
It is analogous to putting a person with normal blood glucose levels on a diabetic diet and not seeing any effect, while in a diabetic, the limitation of sugars, sweets and weight reduction can have significant effects. These are some of the reasons for the confusion, both in the research community and in the news media regarding what is good and what is bad fat.
WHAT YOU CAN DO
Some generalizations can safely be made and serve as guidelines as to what you can and should do. First, find out if you have any reason to need to be concerned about your cholesterol levels, blood pressure, blood glucose or having excess weight. Diets are intended to correct problems.
1. If you have no health problems, it is best to follow a well-balanced mixed diet and enjoy yourself. Eat well and stay in shape. What needs to be done should be determined on an individual basis related to your personal health status, such as your cholesterol levels and blood pressure levels.
2. If you have a need to be concerned about the fat in your diet, then pay attention to the known facts. To lose bodyfat, limit fat intake of all types because all fats are high in calories. It doesn't matter whether it is saturated or unsaturated, you will need to limit your fat intake. You should limit some carbohydrates too, such as sweets and starches.
3. If you need to limit saturated fat, limit your butter fat intake. You are better off to subtitute margarine because most commercially available brands are far better in terms of the body's response to cholesterol production than butter. Butterfat is 66% saturated fat. That doesn't meant the tub and stick margarines are outstanding choices, but they are not as bad as butter in these terms. They are also cholesterol free.
4. Do use one of the cooking oils for food preparation, such as corn oil, canola oil, soybean oil, safflower oil or olive oil - oils low in saturated fat. If you want to take a page from the Italians, you may learn to dip your bread in olive oil or spread olive oil, seasoned to taste, on it. Or you could use another low saturated fat oil of your choice. Remember the calories, though.
5. When thinking of individual foods, remember that the entire diet, not specific items, must be considered. In most instances, using a suitable margarine for some things while using unsaturated oils for the rest of food preparation will meet the requirements to limit saturated fat intake. Liquid margarines in squeeze bottles contain less hydrogenated fatty acids than tub or stick margarine.
6. The next step is to see how such diet modifications work in your individual situation on a long-term basis, not just six weeks. If the diet changes are not adequate, further changes may be needed, more exercise may be required or you may need one of the medicines needed to improve blood cholesterol levels. What counts is what happens in your case, remember everybody diet is different. Individualize, don't generalize.
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