Swamped with patients who have diabetes and are obese, it is often difficult for physicians to dispense advice on a single food item. For instance, often, we give no specific diktat on edible oils.
Sometimes, casual advice when patients are leaving the clinic is: “Don’t take fried food.” Well, that does not include putting a lot of butter on bread or plenty of ghee in daal or on rotis, patients gleefully think. They rationalize — how much harm can this ‘little’ amount do? And then there is that anecdotal evidence. “My grandfather used to take 100 gm of ghee and butter daily and lived up to 95 years!” I explain to them that longevity is a function of a balanced lifestyle of which diet is one of the important components. “Your grandfather must have walked 10-15 km daily and ate plenty of vegetables, fruits and fiber-containing food. But if you are given the kind of fat he consumed, it will burst and burn your liver and heart within a short time with your current lifestyle characterized by little physical activity and an uncontrolled diet.”
Both quantity and quality of the cooking oil is important. There is less controversy about the quantity of oil consumed (including cooking) daily — should be about 3-4 teaspoonful. An oil-less diet will do harm in the long run since essential fatty acids in oils are required by the body. And, beware, even if a particular diet is touted to be ‘zero cholesterol’, there are likely to be more toxic ingredients within.
Researchers and scientists vary in their opinion about quality but some scientific facts have emerged over the past three decades. Remarkable studies done by my colleagues from AIIMS, researching in USA in 1980s, showed that one component of fats, monounsaturated fat (oleic acid), when consumed instead of other fats was highly effective in reducing blood fats and medications in patients with diabetes. While this type of fat is abundant in olive and canola oils, we have used similar mustard oil for centuries (other rich sources are avocados, pistachios, walnuts, almonds and sesame).
The astounding success of ‘Mediterranean diets’ in improving almost all health parameters besides improving the condition of diabetics, averting heart disease and increasing lifespan could be due to daily use of olive oils, among other healthy food items (nuts, also rich in monounsaturated fats; veggies, etc).
The second type of ‘good’ fat’ is polyunsaturated fat (one example is omega-3 fatty acids, found in rich levels in fish). Consuming this type of fat faces two hurdles: fish is often not available and could be contaminated (for e.g. with mercury), and many Indians do not eat fish. In general, levels of these fats are low in the blood of Indians, impacting blood fat levels and heart health adversely. Unfortunately, vegetarian sources of these good fats are few (walnuts, mustard oil, soybean, sesame, peanuts, canola oil, flaxseeds, chia seeds) and contain relatively lesser amounts.
The risk of arterial clogging and heart attacks could be extremely high due to intake of saturated fats though some recent opinions vary. A particularly adverse component of saturated fats is palmitic acids (high in palm oil and dairy ghee), which could also increase growth of cancer cells besides acutely increasing risk of heart attacks. Interestingly, taking even one meal full of saturated fat could lead to explosive break of fats deposited in arteries (plaque rupture), stopping precious blood to brain, heart or anywhere else in the body within seconds. Unfortunately, and contrary to our traditional belief (“ghee is good for strength and heart and lubricates joints”) and our emotional attachment to it, dairy ghee (different from vanaspati ghee which is partially hydrogenated vegetable oil made from dairy sources) and coconut oil are replete with saturated fats (60-80%) and palmitic acid. Robust scientific studies on ghee are few but show a daily intake of even 1-2 teaspoonful increases heart attack risk by more than 10 fold.
Similarly, coconut oil has been found to be raising bad blood cholesterol (LDL, prime determinant of blood artery blockages) in six out of seven good studies done till date. It appears that many people do not believe that coconut oil does any harm to body, basing their opinion mostly on small and poorly executed studies which have little scientific validity.
Finally, bhujias and chips widely available in India are made in saturated fat-laden palm oil. Interestingly, many similar snacks (made by same multinational companies) sold in USA are made with healthier oils!
One up on saturated fat for increasing heart and liver risks are trans fatty acids, abundant in vegetable ghee (vanaspati and many similar oils available in India). High amount of trans fatty acids (about 30-40% in some oils) is injurious to heart, liver, pancreas and blood arteries.
Quite interestingly, our research shows that if you fry/ heat and reheat foods at high temperatures in any oil, the levels of trans fatty acids progressively increase by 100-200 per cent. These cooking practices are common in Indian households and uniformly adopted by street vendors and most food establishments.
So, how do you stay healthy? Your eyes should be open and scanning (looking at nutrition labels for quantity of saturated fats, palm oil, and trans fatty acids), You should consume more fresh fruits and vegetables and taste limited quantities of healthy oils used in rotation and in combination. You should also try not to reuse and reheat any oil. In the polluted atmosphere that we live in, you certainly deserve one less poison.