In my previous post, basic concepts in fats have been discussed. Readers are advised to read the basic concepts before reading this post. In this post role of saturated fats in health and diseases will be discussed.
When fats are eaten, they are broken down during digestion to glycerol and fatty acids (FA). These FA circulate in blood. The cells take FA as per their requirements. When the cell is full, a hormone leptin is released, which tells brain that all cells are full and no further energy intake is required. Its because of leptin, we don’t feel like eating for hours after a fatty meal. Leptin is also called satiety hormone.
Saturated Fats & Heart Diseases
Saturated fats are innocent villains of current dietary guidelines. Saturated fats have been implicated in heart diseases, with the sole assumption that consumption of saturated fat increases LDL (so called Bad Cholesterol), which has been implicated to cause heart diseases. However, the cholesterol theory itself is controversial. Large number of studies are available, which says that high LDL does not causes heart diseases and saturated fats are not linked to heart diseases. On the contrary, saturated fats increase HDL which is believed to be protective as far as heart diseases is concerned. Saturated fats can be termed as heart diseases neutral and foods with saturated fats can be taken liberally. Ghee has been used in pan India and coconut oil has been traditionally used in South India since ages without any marked increase in the heart diseases.
The heart problems have acquired an epidemic proportion in last 25-30 years in India. Advise by professional bodies to cut down saturated fats to <10%, for the fear of increase in cholesterol, has discouraged people from consuming healthy foods like organ meat (liver, brain & kidneys etc), egg yolk, whole milk, cheese, butter, desi ghee, coconut oil etc which are vital source of protein & micronutrients. Non vegetarians deprive themself of micronutrients by restricting to lean meat, as the lean meat is less nutritious than organ meat. Fat of egg yolk and organ meat contains lecithin, a compound that breaks cholesterol, but paradoxically, current guidelines discourage egg yolk and organ meat consumption.
The US Experience
We have not learnt from US experience. After the current guidelines were promulgated in 1961 by the the American Heart Association & USDA in 1980, Americans like good and health conscious people, reduced their intake of saturated fats by 14% and overall fat by 5%. There has been steady decline in red meat consumption in favour of chicken. Since 1978, the total cholesterol has fallen from average of 213 mg/dl to 203 mg/dl (most of the reduction due to drop in LDL). In 1950, Ancel Keys, the founder of cholesterol hypothesis, predicted, that ” if mankind stopped eating eggs, dairy products, meat and all visible fats, heart diseases will be a rare phenomenon”. However, globally onslaught of diseases like Obesity, Diabetes and Heart Diseases remained unabated, and now the average age of onset of these diseases is also decreasing.
Historical Facts
Current guidelines limits energy from saturated fats to be less than 10%, however, historical facts have been ignored altogether during formulation of guidelines. In 1906, Vilhjalmur Stefansson, an anthropologist, while studying Inuit tribesmen of Canadian Artic, observed that about 70-80% of their calories came from fats. The tribesmen always preferred fatty part of meat and leaner parts were fed to dogs. In early 1960s, George V Mann studied Masai tribe in Kenya and found that the staple food of Masai were animal products. They gave fruits & vegetables to cattle. People of Samburu tribe in Uganda drank 2-7 liters of milk every day. All these tribes had blood pressure much lower than their American counterparts, and, most significantly, it didn’t increase with age. A study published in Bioinformation, found that consumption of cow ghee over a period of >6 weeks reduced cholesterol, Triglycerides and increased HDL. Saturated fats have been erroneously implicated in heart diseases. Natural sources of saturated fats are also rich in other micronutrients.
To summarize, saturated fats occurring naturally are not causing heart diseases. I will categorize them in good fats as they improve HDL.
Hydrogenated or partially Hydrogenated Oils
Vanaspati Ghee, also known as shortening is saturated fats prepared artificially by hydrogenation of oils. Anchal, Gagan, Scooter, Rath, Nature fresh, Panghat and Gemini are popular Indian brands of vanaspati ghee. Hydrogenated saturated fats or partially hydrogenated vegetable oils are harmful, as they contain Trans Fatty Acids (TFA). Artificial trans fats are found in fried foods, commercial baked goods, processed foods, etc. Vanaspati ghee is used in bakery as a cheap substitute for butter. It does not melt and make pastry greasy. Naturally occurring trans fats are found in small quantities in meat, milk, and milk products. Artificially produced TFA has been linked to heart diseases and are considered as Bad Fats. According to 2017 estimates, India has the highest burden of heart disease deaths due to high trans fat intake out of all countries in the world. More than 1.5 million deaths each year due to coronary heart disease, and nearly 5 per cent of these deaths each year (71,000) can be attributed to trans fat. FSSAI has laid down the upper limit of trans fat in any product to not more than 2%.
Be aware! a product may be advertised as Trans Fat Free if TFA is less than 2%. One must check the food labels. Best is avoid all artificial trans fats. The real danger of processed foods, street foods & commercial foods is trans fat.
In this post, it has been discussed that, saturated fats are not harmful. They can be taken liberally. Trans Fats are harmful to health.
For more information on fats one must read the book ” A big fat surprise” by Nina Teicholz
Hope you have liked the article. Your comments, criticism and suggestions are welcome.
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