Fats are essential components of our diet. They are Warehouse of energy; one gm of fat storing 9 Kcal of energy (while one gm carbs and proteins give 4 Kcal of energy). Fats are important components of cell membrane. They are precursors of many important molecules and hormones; modulate immune system and provide support to organs. For optimal function of body, the proportion of fat and lean body mass (LBM), comprising of proteins, water & minerals, must be maintained. A male body typically comprise of 85% LBM and 15% fat, whereas a female body comprise of 75% LBM and 25% fat. A female has more fat than a male.
Essential Fatty acids
Fats or fatty acids (we are using them interchangeably) can be synthesized by the body from carbs and proteins, but three fatty acids; Arachidonic acid, Linoleic acid (both are omega-6 fatty acids) and linolenic acid (omega-3 fatty acid) must be supplied through diet, as they cannot be made in the body. These are fatty acids are termed as essential fatty acids (EFA). Deficiency of these EFA may leads to number of problems. Dr Adelle Davis in her book “lets eat right to keep fit” has described a case of 18 month old child, suffering from severe eczema since three weeks of age was cured completely, when he was given EFA in the diet. If a child has chronic eczema, EFA rich diet may be tried if nothing works.
PUFA: Healthy or Harmful?
The consumption of PUFA has gone up, since PUFA have been labelled as a heart healthy oils by American Heart Association, US FDA, WHO etc. People have switched to the refined sunflower oil and other PUFA (advertised as cholesterol lowering and heart healthy in media), shunning traditional cold pressed oils like mustard, peanut and coconut oil. However, the onslaught of heart diseases goes unabated in India as well as globally, which raises doubts regarding the positive health effects of unsaturated fats specially PUFA.
Large number of authors and researchers have started questioning the dietary fat guidelines, that limits fats to 30% of calorie intake and encourages consumption of PUFA and reduction of saturated fats to 10% or less. In a paper titled “The effect of replacing saturated fat with mostly n-6 polyunsaturated fat on coronary heart disease: a meta-analysis of randomized controlled trials“ authors found no significant difference in all-cause mortality or heart disease deaths, resulting from the dietary fat interventions. Two more papers found similar higher death rates in the experimental group given corn oil and safflower & sunflower oils respectively.
Oils high in omega-6 fatty acids promote inflammatory pathways, and omega-3 fatty acids promote anti-inflammatory effects. Its logical to assume that high intake of sunflower oil by Indians may be one of the contributing factor promoting prolonged mild inflammation causing plaque formation and atherosclerosis. All commercial preparations are mostly prepared in refined sunflower oil. Its high time, Indians should switch back to the traditional oils ie mustard oil in North and East India, coconut oil in South India and peanut oil in West India. Ghee, butter, cheese and other products high in saturated fats (not trans fats) should be back. Mustard oil has been labelled as harmful and banned in some countries like US, since it contain erucic acid which have been found to cause heart problems in rats. However, no evidence exists of such effects in humans. Asians have been using mustard oil for generations without any adverse effects. In fact, mustard oil is at par with olive oil in fatty acids composition and has medicinal properties as well. Current guidelines and heart cholesterol connection is not supported by hard science and require a relook. (Those who want to explore further; are advised to read “A big fat surprise by Nina Ticoletz” and “Death by Food pyramid by Denis Menger”).
Few Important considerations for Oils specially unsaturated fats
Unsaturated fats/oils are prone to rancidity due to their chemical structure. PUFA are more prone than MUFA. Saturated fats rancid much more slowly than PUFA or MUFA. PUFA oils become rancid easily on storage due to oxidation leading to formation of aldehydes and peroxides, that are toxic to body. Prolonged heating and repeated reheating also produce trans fats and oxidation products. In restaurants and some homes pre-cooked food is reheated before serving, which is not a good practice in the light of above observation. Most of commercial fish oils and flex seed oils/powder (often used as omega-3 supplements) may be already rancid when bought, unless refrigerated. At home flex seed powder should be prepared in small amount only for a week requirement & should be preferably refrigerated to prevent rancidity. Even roasted flex seeds become rancid on prolonged storage. Due to continuous media publicity, large number of Indian are switching to Olive oil, thinking it to be heart healthy. Olive oil is not suited for Indian type cooking. Only extra virgin olive oil has heart benefits. In Mediterranean region, from where this concept has been copied, people use extra virgin olive oil in salad dressings not for frying. The quality of these Olive oils is questionable even in US, what to talk about India. So using olive oil as heart friendly may not be a good idea.
Omega-3 fats are required for good health. We must include rich sources of omega-3 PUFA ( wheat, mustard, flex seeds, chia seeds, rajma or kidney beans, urd or black gram, fenugreek or methi seeds, eggs, fish and pasture raised meat) in our diet for optimal heart and brain function. Cognitive functions have improved substantially after omega-3 supplements. Rich sources have been discussed in my post on basic concepts of fats.
To improve intake of PUFA, Ayurveda, the ancient Indian medical science, advises people to put few drops of mustard, coconut or sesame oil in the umbilicus and let it get absorbed, on a regular basis. Massage with mustard or any other oil is another good way to get EFA without heat. A word of caution, do not use rancid oils even for external use as the oils get absorbed in the body. For getting maximum vitamin D from sunlight, it is good to have a body massage with coconut or mustard oil and then sit in the sun for half an hour at least. Vitamin D is formed in the skin in the presence of oils on the skin. Sitting in sun after a soap bath will not be of much use as far as vitamin D is concerned.
While talking to some caterers, I came to know that they sell leftover cooked edible oils to street food vendors at cheaper rates (Rs 20/- Kg). Thus each time you eat street food, you are gulping lots of aldehydes and peroxides. Parents must educate their children to refrain from street foods. Even in commercial restaurants chains, frying is continuously done in the same oil for hours at high temperatures, resulting in toxic products, which we eat happily and also pay heavily. For deep frying ghee, coconut oil and mustard oils are better. During cooking, oils should not be subjected to very high temperatures beyond their smoking points. Once a oils starts giving smoke, toxic products will be generated.
Use of refined oil is preferred by all, as it is has better keeping quality than cold press oils but with a heavy cost to our health. During refining oil is extracted by treating the oil to very high temperatures and chemical treatment. It robs the oil from thousands of beneficial chemicals present in micro quantities, which may have beneficial effects due to hormesis. Better to use cold press oil than refined. Cold press oils should be kept in dark and cool places and preferably be refrigerated if possible for maximum benefits.
Important message wrt fats
- Fats are important for health.
- Saturated fats are heart neutral, Trans fats and Omega-6 fats are harmful
- Include Omega 3 rich foods in your diet.
- Indians must start using traditional cold press oils for maximum benefits
- Avoid refined oils or use them infrequently.
- Cooking in oils should be done at low heat.
