First a little history lesson. In 1950’s a researcher named Ancel Keys proposed the lipid hypothesis (LH), which states that there is a direct relationship between saturated fat and cholesterol in diet to the incidence of coronary heart disease. His articles received such widespread popularity that subsequent research and findings to the contrary were drowned out by the popular press. The vegetable oil industry that benefited the most from this study started funding further research to corroborate the lipid hypothesis. In fact the LH has been cited so many times that the medical community forgot that it was merely a hypothesis and not a fact. The fact is that the so called incontrovertible evidence cited in support of this hypothesis is very sparse and non-scientific. Instead consider these facts that refute the lipid hypothesis:
1) Only half the people that die of a heart attack have an elevated serum cholesterol level. Meaning the other half get a heart attack from some other cause other than high cholesterol (perhaps like the dads in Hindi films that get a cardiac arrest when their daughters marry someone other than their chosen groom or vice versa)
2) During the last 5 decades coronary heart disease (CHD) rose as the #1 killer in the US. Currently it stands at 40% of the total deaths. It would then be expected, if the lipid hypothesis were true, that the consumption of saturated fat must have gone up proportionately in the American diet. The truth is the exact opposite. Butter consumption decreased from 18lbs/person/year to 4lbs/person/year during the same period. During the same period the percentage of dietary vegetable oils in the form of margarine, shortening and refined oils increased about 400% while the consumption of sugar and processed foods increased about 60%.
3) The famous Farmingham study that is often cited as the proof for LH is also inconclusive. In this study, done in the town of Farmingham, MA, 6,000 people were divided into two groups and tested at 5-year intervals. One group ate a diet high in saturated fat and cholesterol and the other group ate a diet low in saturated fat and cholesterol. After 40 years the director of this study had to admit: "In Framingham, Mass, the more saturated fat one ate, the more cholesterol one ate, the more calories one ate, the lower the person’s serum cholesterol. . . we found that the people who ate the most cholesterol, ate the most saturated fat, ate the most calories, weighed the least and were the most physically active." The study did show that the people with higher than average weight and with elevated cholesterol levels were at slightly greater risk for CHD but there was an inverse correlation between serum cholesterol level and weight gain and the amount of saturated fat and cholesterol in one’s diet.
4) Now this one is really interesting! In a multi-year research (done by the U.S. Multiple Risk Factor Intervention Trial or MRFIT), studying the eating habits and mortality rates of over 12,000 men it was found that the men with so called “good” eating habits (reduced saturated fat, cholesterol and smoking) showed a marginal reduction in deaths from CHD but their overall mortality from other causes such as cancer, brain hemorrhage suicide and violent death, was higher. Recent research (published in the journal of Psychosomatic Medicine) has found a correlation between higher omega-6 to omega-3 blood ratio and the occurrence of depression as well as the presence of inflammation causing compounds in the blood. In light of recent research findings and the MRFIT study, it’s not surprising to know that vegetable oils are rich in omega 6 fatty acids but poor in omega 3 fatty acids. On the other hand butter from grain fed cows has omega-3 and so does the fat found in eggs yolks. Olive oil is 18% saturated fat and is also a rich source of omega-3 and of course fish body oils are rich in this essential (for brain) fatty acid. The real cause for CHD is now thought to be the inflammation promoting compounds in the blood and not total cholesterol levels, but this is a topic for discussion that I intend to take up some other time.
5) We all know that mother’s milk is essential for growth and brain development in children. But how many of us know that mother’s milk has the highest proportion of cholesterol than any other food. Also 50% of the calories in mothers milk come from fat, much of it saturated fat. A recent study [1] has shown that in growing children a diet lower in saturated fat might interfere with normal growth and development.
6) A comparison of mortality rates due to CHD in northern and southern India has shown that the mortality rate is 20/100,000 in northern India compared to 135/100,000 in southern India. The study concluded that the mortality rate from heart attacks in north India is 7 times lower than that in south India even though the people in north India consume 17 times more saturated fat from animal sources and clarified butter (ghee) than the people in south India.
7) Several studies done in Europe have shown that people in Switzerland, France and Italy who survive on one of the most fattiest and cholesterol rich diets consisting of organ and liver meats, cheese and butter and who have the highest total serum cholesterol levels (over 300 in some areas), also have one of the longest average lifespans. The incidence of CHD is negligible in these same areas compared to that in the U.S.
8) The Japanese who have the longest average lifespan are known for their love of seafood and shell fish. Some fish like cod and salmon are moderately high in cholesterol but most shellfish like shrimp, lobster and crab have very high cholesterol content.
Now it doesn’t sound like saturated fat and cholesterol are the twin villains of modern diet, does it? So what are the main culprits in the CHD epidemic that is sweeping the developed world? The real villains behind this are thought to be refined and processed flours, hydrogenated vegetable oils and trans-fats and simple sugars in the modern diet. The other big villain, the Mogambo (if you don’t know who that is you need to watch more Hindi films) of heart disease is stress, but that’s a separate topic in and of itself.
Now I am not suggesting you go and eat all the butter you can with a 6-egg omelet every morning and hope to be free of any risk for CHD. You first have to make a lifestyle change to include healthy whole grains, fruits and nuts in your diet, exercise moderately (or intensely) 3 times a week and try to address the stress in your life. If you can incorporate these healthy changes then you will benefit from moderate amounts of organic butter, whole eggs and even the meat in your diet. Remember, saturated fat is not the enemy but refined and processed foods and inactivity is. Lord Krishna said about inactivity in the Gita “Perform your prescribed duty, for doing so is better than not working. One cannot even maintain one’s physical body without work.” So work your body hard and in return let it work for you for a long time.
References:
1) 10. Lifshitz F, Moses N. Growth failure: a complication of dietary treatment of hypercholesterolemia. Am J Dis Child. 1989; 143: 537–542.
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