Day after day, in the process of cooking, we either stir-fry, sauté, deep fry or sprinkle our food with oil. As a result, a great deal of this is consumed; little wonder then that it plays a big role in creating wellness. The right cooking oil can give you the best benefits in terms of taste, texture and nutrition.
"Apart from enhancing the palatability of food, it also plays a vital role in regulating the metabolic functions of the body," says Dr Nupur Krishnan, clinical nutritionist and director of Bio-logics Healthcare in Mumbai. "It supplies us with energy and helps us absorb fat-soluble vitamins (A, D,E and K, which are important nutrients). It also enables our bodies to metabolize proteins and carbohydrates more effectively, promoting digestion. It gives one a feeling of fullness and acts as an insulator to maintain body temperature." And that's why even dieters shouldn't severely restrict their use of oil.
Going overboard can be bad
Despite the many benefits of oils, too much of this in our diet can cause major health problems, particularly by increasing LDL (bad) cholesterol and paving the way to heart disease. It helps to remember that there are no 'low calorie' oils. "One teaspoon of any oil gives you 45 calories of energy," says Saritha Rajiv, Delhi-based nutrition and diet consultant. The recommended intake of oil is 4-5 teaspoons for a healthy person and 2-3 teaspoons for anyone suffering from a chronic illness, adds Dr Nupur Krishnan.
With dozens of options, choosing the right cooking oil can be a confusing task. "Your choice of cooking oil should depend on the type of cooking method you employ," says Saritha Rajiv. "If you're deep frying, use oils that have a high smoking point (oils that tolerate high temperatures and don't get charred easily). Refined vegetable oils such as sunflower and safflower have a high smoking point. For stir frying and sautéing, one should use oils such as olive, peanut and canola. Extra virgin olive oil and flaxseed oils are best used in salad dressings."
Know your MUFA’s and PUFA’s
Some oils are a rich source of essential fatty acids such as MUFA (monounsaturated fats) and PUFA (polyunsaturated fats). Essential fatty acids are 'essential' because our bodies are not able to synthesize these. So we definitely need to consume these fatty acids from the foods/oils we eat. This includes Omega 3 and Omega 6 fatty acids that are responsible for regulating many of our metabolic activities.
"MUFA is found in groundnut oil, olive oil, mustard oil, peanut oil and canola oil," says Dr Nupur Krishnan. "It's important because it helps lower LDL (bad) cholesterol and maintain HDL (good) cholesterol. Hence it improves the LDL/HDL ratio in our bodies, thereby reducing the risk of heart disease. Polyunsaturated fats are found in vegetable oils such as safflower, sesame, corn, cottonseed and soybean oils. This type of fat reduces the levels of LDL cholesterol too, but too much of this can lower the good HDL cholesterol's well, so it is best to use caution while consuming PUFA's." Experts advise the use of both kinds of oil in our daily diet.
"Always keep two different oils (one with MUFA and another with PUFA) in your kitchen and consume these on alternate days or on a weekly rotation. This will help maintain balance and give you all the essential nutrients," says Dr Nupur Krishnan. Don't ever be tempted to mix two different oils, especially at home by yourself. "This can only be done during the manufacturing process," she advises.
Beware of over heating and hydrogenation
It's important to store your oil right. "All oils should be kept in a cool, dry place in an airtight container," says Saritha Rajiv. "Prolonged consumption of burnt oils can lead to several health problems. However, oil can be re-used provided it has not been overheated on first use. Used oil should be strained and cooled well to remove any food particles before storage, otherwise microbes can grow on food particles, leading to rancidity. Rancid oils contain free radicals that increases one's risk of contracting cancer."
To increase the shelf life of the oil and prevent rancidity, sometimes oils are 'hydrogenated' or partially hydrogenated. This is done during the manufacturing process when hydrogen is added. "Partially hydrogenated vegetable oils can be harmful for your health and tend to increase bad cholesterol and heart attack risk, so read food labels carefully and completely avoid these oils," advises Saritha.
Refined and unrefined
When you buy refined oil, what exactly are you getting? Refined and filtered oil denotes an elaborate manufacturing process, meant to produce oils that are completely devoid of taste, smell and colour. Filtration is done to further free it of impurities and when oil is 'double filtered', it has even more clarity. While refined oils are meant to bring out the natural flavours of foods that we eat, they can be too bland. Over the years, nutritionists have pointed out that the process of refining oil can strip it of its minerals, beta carotene and much of its Vitamin E content. So how can you as a consumer identify this? Dieticians recommend that you read the food labels.
As oils with lower levels of betacarotene and Vitamin E spoil easily, manufacturers tend to add synthetic ingredients such as BHA and BHT to extend shelf-life. If you find these on the food label, you'll know that this is a refined oil that should be avoided. However, as a rule of the thumb, refined oils do tend to have a longer shelf-life than the unrefined kind. Unrefined oils are more natural and tend to retain the original flavour of the nut or seed from which these were extracted, but many people find that these completely overpower the natural taste of the cooked food, so do a little introspection before making the right choice for your family.
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