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HEALTHWATCH

PHOTO: SHAJU JOHN

Choosing well: Oils that have a high MUFA content are better for your health.

Some 25 years ago, buying oil for your home was perhaps not so difficult, because of the limited varieties that were sold. In South India it was the til, groundnut, safflower or the sunflower oil that was most bought and used. And then, there was the hydrogenated fat which was a substitute for ghee for frying and making sweets. Today, most housewives are often confused when it comes to buying the oil that will ensure optimal health. They are bombarded with ads that brag about products that contain no cholesterol or contain omega 3 fatty acids which can promote a string of health benefits.

Fats and oils are an essential part of the diet and serve a variety of functions in the body. They are concentrated sources of energy and supply nine kcal per gram. One teaspoon of oil will supply about 40 kcal.

Fats are solids at room temperature and include butter, ghee, margarine and the hydrogenated varieties while oils are liquids. Fats that are present in specific foods such as milk and nuts are called “invisible fats” while the ones that are bought for cooking purposes are called the “visible fats”. The visible fats and oils can be obtained from a variety of animal and vegetable sources.

All fats and oils are made up two essential ingredients — glycerol and fatty acids. Glycerol in the fat does not exert a significant influence on health. On the other hand, there are many different types of fatty acids and these will determine how healthy you will be. Some fats, when used as the principal cooling medium, promote our health positively while some increase our risks of diseases, especially cardiovascular diseases. The key is to replace bad fats with good fats in our diet.

So what are the different types of fatty acids? Fatty acids can be saturated, monounsaturated (MUFA) or polyunsaturated (PUFA). Within the category of PUFA are the trans fatty acids and the omega-3 fatty acids.

You get saturated fatty acids from the fat found in milk and its products such as ghee and butter, eggs and meat products. Some plant sources such as coconut and palm oil and the hydrogenated fats are also high in saturated fatty acids. Recipes prepared using these products will be high in saturated fatty acids. Saturated fatty acids have been associated with increase in total cholesterol and LDL cholesterol (bad cholesterol) levels. Studies support the concept that restricting saturated fat and cholesterol reduces the risk of cardiovascular diseases.

Nut oils (like peanut oil and til oil), olive oil and canola oil are high in MUFA. Why is olive oil so much in the news today? Because, it’s a heart-friendly oil and if you prefer MUFA over saturated fatty acids in your diet, you could protect yourself against elevation of total cholesterol and LDL cholesterol. Your cholesterol levels may actually reduce if you substitute MUFA for saturated fatty acids.

Food sources of PUFA include the vegetable oils (corn, soyabean, safflower, and sunflower), with the exception of coconut and palm oil. Most have a cholesterol lowering effect when substituted for dietary saturated fatty acids. They also lower LDL cholesterol and could elevate the “good” HDL cholesterol. Oils high in PUFA are however likely to spoil sooner than those high in saturated fatty acids. Buy these oils in small quantities and store them well.

Fatty acids that can significantly contribute to good health are called Omega-3 fatty acids. Omega-3 fatty acids are valued for their ability to reduce the triglyceride levels (a risk factor for cardiovascular diseases), lower the blood pressure, decrease the formation of blood clots and reduce the risk of cardiovascular diseases and sudden cardiac deaths. Despite a high fat diet, Japanese and Eskimos have a low rate of heart diseases and the protective component in their diet is undoubtedly the omega-3 fatty acids in the fish.

Arthritic patients and people with Psoriasis, the scaly condition of the skin, may also benefit from omega-3 fatty acid intakes.

Fish is an important source of Omega-3 fatty acids. If you are a vegetarian, do not be concerned. You could boost your intake of omega-3 fatty acids through flax seeds and walnuts. Omega-3 fatty acids are also found in smaller amounts in green leafy vegetables like spinach, nut oils and soya oil.

A fairly new concern involves the concentration of trans fatty acids in the diet. Trans fatty acids have been shown to elevate LDL cholesterol and reduce the HDL cholesterol. Trans fatty acids are formed during the hydrogenation of vegetable oils. Hydrogenation is a processing technique that converts vegetable oils such as soya oil to a semisolid state. This also makes the fat less likely to spoil. Hydrogenated fats such as margarine (vegetable shortenings) are high in trans fatty acids. Trans fatty acids are found in most commercial snacks such as finger fries, samosas and many baked items such as cookies and cakes. Since 2006, in the United States, trans fatty acid content of foods is required to be mentioned on all labels for foods that contain at least half a gram of total fat per serving. Margarine devoid of trans fats and labelled “trans fat-free” is available in the U.S.

Cholesterol is found only in fats from animal sources like butter and never in vegetable oils.

It is apparent that the saturated and trans fatty acid contents must be low and the best way to achieve this is to limit the amount of oils such as coconut and palm and solid fats like butter, margarine and shortenings you add to food when cooking and serving. It must be mentioned that there are conflicting reports about the health effects of coconut oil.

While the kind of fat is important, it is also necessary to take note of the amount of fat in your diet. Moderation in the use of fats is essential.

How much of fat should you include in your diet? You are advised to limit your intake of fat to less than 30 per cent of the total calorie intake. If you are on a 1500 kcal diet, then fats should supply only 450 kcal and this amounts to 50 gm of fat. This, of course, includes both the invisible and the visible sources of fat. A safe bet would be to include about 25 to30 g of visible fat in your diet every day. Not enough? Switch to non-stick pans and measure your oil in teaspoons.

Decrease the saturated fat intake to less than seven per cent of energy and maintain the dietary cholesterol to < 200 mg/d. This would mean cutting down on butter, margarine, ghee, vanaspathi, coconut and palm oils and limiting high cholesterol foods like eggs. Ban trans fatty acids from your meals.

So, what’s the cooking oil that’s good for you??

While selecting the fat that is optimal for health and for use on a regular basis, choose the one that is rich in MUFA, containing reasonable amounts of PUFA and one that is low in saturated fatty acids. It should be free from trans fatty acids. On this basis the “bad” oils would be vegetable shortenings and margarine (because of their high content of trans fatty acids), butter, palm oil, palm kernel oil and coconut oil (because of their high content of saturated fatty acids; http://www.healthcastle.com/coconut-saturated-heart.shtml ). There is of course no harm in using small amounts of butter or coconut oil occasionally.

The ideal oil may be canola oil or olive oil because of their low levels of saturated fatty acids and a high amount of monounsaturated fatty acids. They are more suited in the preparation of salad dressings and sautéing or stir frying. But, their availability in India is limited and their cost is prohibitive. For Indian homes, nut oils such as til oil or peanut oil and rice bran oil, which are high in MUFA, would be a good choice. Soya bean oil, corn oil and sunflower oil have a slightly lower amount of MUFA and are higher in PUFA.

What is being recommended today is a combination of oils. Such blends are available in the market. Rather than going for these blends, select two different oils for cooking — may be rice bran and sunflower oil or til oil and soya oil. Use oils with a high smoke point (those that can be heated to high temperatures) such as corn oil, safflower oil, sunflower oil for deep fat frying, while olive oil and peanut oils are recommended for stir frying and salad dressings.

So, next time you are in the supermarket, read the label and debate before you choose your oil.

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