Poor old saturated fat. For over forty years now, it’s been spoken of only in hushed tones, dissed as nothing but artery clogging, obesity-causing poison. This “common sense fact” has become so widely accepted that a lot of people who want to improve their diet start by purchasing skim milk, ditching their egg yolks, and beginning a life free of steak, pork, and butter.
It’s time to bring bacon back to breakfast. After all, saturated fat is good for you.
We’ve Made a Huge Mistake
But we all make mistakes. This one started in 1970, with the first publication of “The Seven Countries Study .” The research looked at the incidences of saturated fat intake and heart disease among 12,763 men from (you guessed it) seven different countries, and showed a correlation between the two.
Unfortunately, the study was deeply flawed: It didn’t take into account important factors like smoking rates, sugar consumption, and exercise levels, and it left out an awful lot of data from other countries that contradicted the conclusions. The study’s authors actually had access to twenty-two countries’ data, and didn’t discuss any of the populations that followed diets with plenty of saturated fat and barely experienced any heart disease. Such communities include the Kenyan Masai, the Tokelau in Polynesia, and the Arctic Inuit.
Governments followed by making the supposed saturated fat-heart disease connection a matter of public health policy, an ideology which probably culminated with the abominable food pyramid of the 1990s — which recommended up to 11 servings of rice and pasta per day, and about as little fat as possible.
The result? In the past 30 years in the United States, the amount of calories from consumed fat has fallen from 40 percent to 30 percent, while obesity has doubled and heart disease has remained the country’s number one killer.
But the spread of obesity has no single cause; there are a lot of complicated factors that have led to America’s health crisis. To figure out whether saturated fat should be added back into our diets, let’s take a closer look at its effect on the body.
Why Saturated Fat Doesn't Cause Heart Disease
In a 2010 evaluation of 21 studies and 350,000 subjects, saturated fat was not associated with an increased risk of coronary heart disease — and numerous other studies have reached similar conclusions Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. Siri-Tarino PW, Sun Q, et al. American Journal of Clinical Nutrition, 2010 Mar; 91(3):535-46. Saturated fat and cardiovascular disease: the discrepancy between the scientific literature and dietary advice. Hoenselaar, R. Department of Nutrition and Dietetics, High School of Arnhem and Nijmegen, The Netherlands. Nutrition. 2012 Feb;28(2):118-23. The questionable role of saturated and polyunsaturated fatty acids in cardiovascular disease. Ravnskov U. Journal of Clinical Epidemiology, 1998 Jun;51(6):443-60. Dietary polyunsaturated fatty acids and composition of human aortic plaques. Felton CV, Crook D, et al. The Lancet, 1994 Oct 29;344(8931):1195-6. Saturated fat prevents coronary artery disease? An American paradox. Knopp RH, Retzlaff BM. American Journal of Clinical Nutrition, 2004 Nov;80(5):1102-3. Dietary fats and health: dietary recommendations in the context of scientific evidence. Lawrence GD. Advances in Nutrition, 2013 May 1;4(3):294-302. Dietary saturated fat intake, is there really an association with coronary heart disease? Rehman MS, Student RI. Journal of Pakistan Medical Association, 2012 Apr;62(4):411. Saturated fat, carbohydrates and cardiovascular disease. Kuipers RS, de Graaf DJ, et al. The Netherlands Journal of Medicine, 2011 Sep;69(9):372-8.. Of course, these studies aren’t without controversy. For instance, Greatist expert and physician Dr. James Hardeman believes those 21 studies aren’t comprehensive enough; on average, their subjects were studied for around 14 years, which may not be long enough to see the effects of a diet high in saturated fat. However, they raise important questions about saturated fat’s effects on the arteries of the heart and brain.
But what about cholesterol? We actually have two kinds of cholesterol in our blood: the HDL (“good”) and LDL (“bad”). Total cholesterol levels are less important than the ratio of HDL to LDL, but a simpler (if kind of flawed) approach is that we should try to increase HDL and decrease LDL. Saturated fat is generally believed to increase the bad cholesterol.
But that’s only part of the story, because there are also two kinds of LDL cholesterol: big, floaty particles (type A) and small, dense ones (type B). When someone reduces their consumption of saturated fat and their LDL cholesterol “drops,” they’re only lowering their type A particles. But it’s the type B particles that are more closely linked in heart disease, and they’re generally controlled by carbohydrate consumption Atherogenic dyslipidemia: cardiovascular risk and dietary intervention. Musunuru K. Lipids. 2010 Oct;45(10):907-14.. So the best way to cut out harmful types of cholesterol and reduce the risk of heart disease could be to follow a diet that’s low in carbs, rather than fat The national cholesterol education program diet vs a diet lower in carbohydrates and higher in protein and monounsaturated fat: a randomized trial. Aude YW, Agatston AS, et al. Journal of the American Medical Association - Internal Medicine, 2004 Oct 25;164(19):2141-6. Effects of dietary composition on energy expenditure during weight-loss maintenance. Ebbeling CB, Swain JF, et al. Journal of the American Medical Association, 2012 Jun 27;307(24):2627-34. Effects of a low-carbohydrate diet on weight loss and cardiovascular risk factor in overweight adolescents. Sondike SB, Copperman N, et al. Journal of Pediatrics, 2003 Mar;142(3):253-8. A randomized trial comparing a very low carbohydrate diet and a calorie-restricted low fat diet on body weight and cardiovascular risk factors in healthy women. Brehm BJ, Seeley RJ, et al. The Journal of Clinical Endocrinology & Metabolism, 2003 Apr;88(4):1617-23. A low-carbohydrate, ketogenic diet versus a low-fat diet to treat obesity and hyperlipidemia: a randomized, controlled trial. Yancy WS Jr, Olsen MK, et al. Annals of Internal Medicine, 2004 May 18;140(10):769-77. Carbohydrate restriction has a more favorable impact on the metabolic syndrome than a low fat diet. Volek JS, Phinney SD, et al. Lipids. 2009 Apr;44(4):297-309. Long-term effects of a very-low-carbohydrate weight loss diet compared with an isocaloric low-fat diet after 12 months. Lim SS, Noakes M, et al. Nutrition, Metabolism and Cardiovascular Diseases, 2010 Oct;20(8):599-607. Lack of suppression of circulating free fatty acids and hypercholesterolemia during weight loss on a high-fat, low-carbohydrate diet. Hernandez TL, Sutherland JP, et al. American Journal of Clinical Nutrition, 2010 Mar;91(3):578-85..
Why Saturated Fat Can Be Good For You
Saturated fat has been shown to have loads of positive effects on the body, including:
- Liver Health: Saturated fat encourages the liver cells to dump their fat cells, which helps the liver to function more effectively Dietary saturated fatty acids: a novel treatment for alcoholic liver disease. Nanji AA, Sadrzadeh SM, et al. Gastroenterology. 1995 Aug;109(2):547-54. Opposite effects of dietary saturated and unsaturated fatty acids on ethanol-pharmacokinetics, triglycerides and carnitines. Cha YS, Sachan DS. The Journal of the American College of Nutrition, 1994 Aug;13(4):338-43..
- Immunity: Saturated fatty acids, especially the kinds found in butter and coconut, help white blood cells to recognize and destroy invading viruses and bacteria. Go get ‘em, boys!
- Hormones: Eating saturated fat tends to increase free testosterone levels, which helps to repair tissue, preserve muscle, and improve sexual function Effects of dietary fat and fiber on plasma and urine androgens and estrogens in men: a controlled feeding study. Dorgan JF, Judd JT, et al. American Journal of Clinical Nutrition, 1996 Dec;64(6):850-5. Testosterone and cortisol in relationship to dietary nutrients and resistance exercise. Volek JS, Kraemer WJ, et al. Journal of Applied Physiology, 1997 Jan;82(1):49-54..
Now, fat is high in calories, so it can promote weight gain in that respect. Per gram, it has more than twice the calories of protein or carbohydrates. But provided an eye is kept on portion size, saturated fat in and of itself doesn’t have any negative impact on the body. In fact, increasing fat intake might help with weight loss: One study found that when three groups of obese people were fed diets of 90 percent fat, 90 percent protein, and 90 percent carbohydrates, respectively, the high-fat group lost the most weight Calorie intake in relation to body-weight changes in the obese. Kekwick, A, Pawan, GL. The Lancet, 1956 Jul 28;271(6935):155-61.. Plus, it tastes freaking delicious.
DROP THAT HOT DOG!
This doesn’t mean every source of saturated fat is healthy. Case in point: A study from the Harvard School of Public Health found that after analyzing the diets of 1.2 million people, there was no association between eating red meat and heart disease — but there was for those who ate a lot of processed meat Red and processed meat consumption and risk of incident coronary heart disease, stroke, and diabetes mellitus: a systematic review and meta-analysis. Micha R, Wallace SK, et al. Circulation. 2010 Jun 1;121(21):2271-83. . That is to say, if we’re going to get sick from eating meat or saturated fat, it’ll be by getting it from a crappy source.
Basically, we should spend a little more on food. The body loves saturated fat, but from sources like grass-fed meat and butter, whole eggs, and coconut fat — not hot dogs and pepperoni pizza (sorry). By a mile, the biggest enemy in our food is likely refined sugar Sugar restriction: the evidence for a drug-free intervention to reduce cardiovascular disease risk. Internal Medicine Journal, 2012 Oct;42 Suppl 5:46-58.. Even the American Heart Association, which is still anti-saturated fat, agrees that sugar is a far bigger contributor to heart disease.
But the tide is very slowly starting to turn. Prominent journals and scientists are beginning to speak out on saturated fat’s benefits, and, after government scientists reviewed 16,000 studies on diet and obesity, Sweden recently became the first Western country to advocate a high-fat diet to its citizens.
That’s because heart disease and obesity are caused by inactivity, trans fats, refined carbs, and overeating, to name a few — but not saturated fat. Toss the margarine and tuck into some buttered vegetables or a seared steak. We think you deserve it.
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