Bad fats, good omega-3s, mono-fats, poly-unsaturated fats, trans fats … What’s the best kind for you?

The variety of cooking oils and fats available today and the claims made by them are, at best, confusing. On one side are the traditional ghee, mustard oil, coconut oil and gingelly oil. Then there are the used-for-decades vanaspati and groundnut oil as well as the relatively newer kinds of vegetable oils ranging from sunflower, safflower, corn, canola, soybean, cottonseed and palm to various blends. Olive oil is the latest ‘foreign’ oil exciting the health-conscious. Buying the right oil for health has become a big deal.

Fat factor

Let us begin at the beginning. First, cooking oil is pure fat obtained from plants or animals. Whether from plants or animals, one gram of cooking oil or fat provides about nine calories. Experts recommend a total of 20 gm or four teaspoons of oil for an adult.

Second, the type of oil being consumed determines a person’s risk of heart disease. All cooking oils are made up of a combination of fatty acids, which may be saturated, mono-unsaturated or poly-unsaturated. Their relative proportions classify the oil as saturated, mono-unsaturated or poly-unsaturated.

Saturated fats — found in animal fats like ghee, butter, lard (fat in meat) — are solid at room temperature and raise LDL (bad) cholesterol in blood. At the same time, they reduce HDL (good) cholesterol. Good for infants and young children, these fats are a definite no-no for heart health. Plant oils like palm oil (palmolein) and coconut oil are also very high in saturated fats and should be totally avoided.

On the other hand, both mono-unsaturated (MUFA) and poly-unsaturated fats (PUFA) are considered ‘good’ fats because they lower total and LDL cholesterol. Ideal cooking oil requires a balance between MUFA and PUFA levels. Also, since omega-3 fatty acids are extremely good for the heart, selecting an oil rich in omega-3s is important. So which oil is good for cooking?

Mustard oil, canola (rapeseed) oil, olive oil and groundnut oil have the best combination of good and bad fatty acids. Gingelly oil is another excellent option. Soybean, corn, sunflower and safflower oils have low saturated fatty acid content though MUFA content is lower than the PUFA content, which is not desirable.

A word about mustard oil: Used in India since time immemorial, recent research lauds mustard oil as ideal. A study by Harvard School of Medicine, All India Institute of Medical Sciences (AIIMS), New Delhi, and St. John Hospital, Bangalore, found that chances of heart disease drop by nearly 70 per cent when mustard oil is used for cooking. Moreover, its nutritional benefits compare well with the much-hyped olive oil at one-sixth the cost. Cooking in mustard oil (especially the cold-pressed or kachchi ghani variety) could be the wisest health investment one can make.

To fry in

Now, which oil is best for frying? The high heat during frying decomposes or breaks down the oil producing cancerous substances. So, the best oil for frying is one that can withstand the high temperature without foaming and smoking. Groundnut and gingelly oil are especially good for frying.

All said and done, the best bet is to use a variety of oils judiciously. A combination of oils ensures a healthy intake of all important fatty acids. You may also like to rotate the good oils over the months. So, use mustard, sesame, canola or olive oil (extra light or refined) for cooking; groundnut oil for frying; and olive oil (extra virgin) for salads and pasta. With cooking oil, less is more.

Speaking of fats, one can’t ignore the latest demon on the health scene: trans fats or vegetable oils that have been partially hydrogenated. Food manufacturers add hydrogen to liquid vegetable oils and heat them. This hardens the oil and increases shelf life. Foods made with such partially hydrogenated fats have better texture, flavour, taste and spreadability.

In India, vanaspati is the best example of trans fats. Though use of vanaspati in homes is falling, restaurants, fast food joints, takeaways, canteens, flight/railway kitchens, street-side stalls, dhabas and halwais use vanaspati hugely.

Why they’re bad

The processed food industry loves trans fats. You will find it in biscuits, crackers, cookies, rusks, breads and buns, breakfast cereals, bread spreads and salad dressings, cakes and cake mixes, microwave popcorn, pizza, burgers and French fries, heat-and-eat curries, artificial creamers, chocolates and candy, mithai and ice cream.

If trans fats make food so tasty, why are they bad? Trans fats foul up the body’s entire machinery. They cause weight gain and excess abdominal fat — both risk factors for heart disease and diabetes. They increase LDL cholesterol, which clogs up arteries, and lower d HDL cholesterol, which would otherwise take HDL cholesterol to the liver where it would be broken down and excreted. Trans fats interfere with metabolism of fats and elevate blood triglyceride levels. If one continues to eat trans fat-rich foods, it sets the stage for a heart attack.

There is no safe limit for trans fats. Some amount of trans fats are found in whole milk and meats but this is too small an amount. Also trans fat found naturally in animal fats is much less harmful than that found in partially hydrogenated oils.

But, remember, most of us need to curb the total amount of fat in our diet.

The writer is a Nutrition and Health researcher and the author of The Power of N: Nutrition in our times

Wholesome tips

As a general rule, cook wholesome meals at home with healthy oils.

When shopping, avoid foods that mention shortening, hydrogenated or partially hydrogenated oil as an ingredient.

Since it is now mandatory to put trans fats content on the label, choose foods with no trans fats.

Avoid eating at roadside dhabas, takeaways and halwais.

Restrict eating out to once a month. Avoid gravies, creamy sauces and salad dressings. Opt for stir-fried over fried and grilled over curried.

More In: Magazine | Features