Is it possible — even imaginable — that nearly everyone has been wrong about saturated fat and its connection to heart disease? Brace yourself. Based on a wave of new research, all the dietary admonitions about saturated fat could end up being little more than a huge mistake.
“The question is whether saturated fat is harmful or is just a bystander,” says Ronald M. Krauss, MD, a lipid specialist and the director of atherosclerosis research at the Children’s Hospital Oakland Research Institute. “Saturated fat may have an effect on cardiovascular disease (CVD) risk, but the effect is so small that we just can’t detect it. We shouldn’t be demonizing saturated fat.”
Krauss can back up his opinion with hard science. He and his colleagues recently analyzed 21 published studies involving almost 350,000 people who were tracked from five to 23 years. Their conclusion: People who consumed the most saturated fat did not have a higher risk of heart disease, stroke or any other form of CVD. They published their findings last year in the American Journal of Clinical Nutrition.
Krauss is by no means the first doctor to question the role of saturated fat in CVD. But, if he and other critics are right, it raises a couple of important questions: How could anti-saturated-fat advocates make such a huge miscalculation? And do we now have a license to eat saturated fat with abandon?
The answers aren’t as simple or straightforward as you might think.
There’s no denying that scores of studies over many years have shown a link between saturated fat and CVD risk. Krauss believes, however, that many of the saturated-fat-is-bad studies have not accounted for diets that included a lot of sugars, refined carbs and trans fats, along with saturated fats.
“It doesn’t make sense to focus on just one feature of the diet, such as saturated fat, while ignoring the health effects of the overall diet,” he says.
Origins of a Theory
The late Ancel Keys, PhD, a researcher at the University of Minnesota, first linked saturated fat and cholesterol with the risk of CVD in the 1950s.
Keys was hailed as a pioneer in the area of nutrition and health at the time; in January 1961, he made the cover of Time. Less than 20 years later, Congress was recommending that Americans ditch saturated fats in favor of more carbs, and soon food companies were hawking low-fat everything.
Keys’s research has come under increasing criticism in recent years. Gary Taubes, author of Why We Get Fat and What to Do About It (Knopf, 2011), notes that Keys focused on the eating habits linking saturated fat to CVD in seven nations, “in which he could pretty much draw a straight line between saturated fat and CVD risk.”
According to Taubes, Keys ignored contradictory data from other nations, including France, where people ate a lot of fat but had a low incidence of CVD (the so-called French paradox), which would have led Keys to draw entirely different conclusions.
“More than 20 studies have shown that people who have heart attacks don’t eat more saturated fat than healthy people,” says Swedish researcher Uffe Ravnskov, MD, PhD.
Ravnskov, who has written several books on cholesterol, has been skeptical of the saturated fat–cholesterol theory of heart disease since the 1960s. “Eight studies have shown that people with stroke have eaten less saturated fat than healthy people,” he says. “And no dietary study has succeeded in lowering heart disease deaths by reducing intake of saturated fat.”
Enter Refined Carbs
Americans largely embraced the anti-saturated-fat gospel, substantially cutting their consumption from about 13.5 percent of total calories in the early 1970s to about 11 percent of calories by 2000. In 2006, the American Heart Association recommended that people cut their saturated fat even more — down to 7 percent of total calories, which is half of what people were eating 40 years ago. But there have been unforeseen consequences, Krauss notes. “If you cut down on saturated fat, what do you replace it with?”
Food manufacturers responded by creating thousands of products in which saturated fat and cholesterol were replaced with refined carbohydrates, sugars and trans fats. And therein lies the problem. Not only do trans fats drive bodywide inflammation, but foods rich in refined carbohydrates and sugars trigger sharp increases in blood-sugar and insulin levels, which then set the stage for weight and blood-sugar problems — the leading risk factors for type 2 diabetes and CVD. “Replacing saturated fat with refined carbohydrates and sugars does not decrease CVD risk,” says Krauss. “More and more, the evidence shows that eating more refined carbs and sugars increases CVD risk.”
The late Robert C. Atkins, MD, sounded the alarm about the increase in carb and sugar consumption in the 1980s, when he noticed a dramatic rise in obesity and type 2 diabetes. But his solution, a diet rich in saturated fats, was roundly criticized — mostly because people believed that Atkins advised avoiding all carbs, including vegetables, when, in reality, he meant refined carbs. It took years of research before his approach was eventually vindicated.
This may sound like heresy, but the science behind it is solid. Sabina Sieri, PhD, of Italy’s National Cancer Institute, for example, tracked almost 48,000 people over eight years and found that women who ate more refined carbs and sugars had a significantly greater risk of coronary heart disease than those with a lower refined-carb intake.
The Cholesterol Question
For several decades, medical and nutritional advice boiled down to this: Too much dietary saturated fat leads to higher levels of blood cholesterol and an increase in CVD risk. But several studies have shown that total blood cholesterol is not a reliable indicator of CVD risk, says Ron Hunninghake, MD, chief medical officer of the Riordan Clinic in Wichita, Kan., the largest nonprofit nutritional medical center in the United States. “That’s because half of the people who suffer a heart attack have normal cholesterol levels.”
To find a way to make sense of the relationship between blood cholesterol levels and CVD, researchers began looking at cholesterol fractions, such as low-density lipoprotein (LDL) and high-density lipoprotein (HDL), to get a better handle on CVD risk. These LDL particles happen to be one of Krauss’s primary areas of expertise, and his findings have challenged conventional thinking about the role of saturated fat and cholesterol in CVD.
Although LDL is widely regarded as the “bad” cholesterol, Krauss argues that it has a good side: While “pattern B” LDL consists of small, dense particles that are more likely to infiltrate blood-vessel walls and set the stage for blockages, high blood levels of “pattern A” LDL, which consists of large, fluffy particles, are associated with a lower risk of CVD.
It’s true that saturated fat does increase LDL levels, Krauss explains — but not in the way most people would expect. “We’ve shown in our own research that in the great majority of individuals, this increase in LDL reflects an increase in pattern A LDL.” That’s the good form of LDL. Saturated fat also boosts levels of the “good” HDL form of cholesterol.
Diets high in refined carbs, on the other hand, boost pattern B LDL and lower HDL cholesterol — thereby increasing the risk of CVD. “Little will be gained if saturated fat is simply replaced by carbohydrates, especially if these are mainly refined starches and sugar,” says Walter Willett, MD, DrPH, who heads the nutrition department at the Harvard School of Public Health.
Research by Marianne U. Jakobsen, PhD, of Aarhus University Hospital in Denmark, supports this argument. In a study of more than 53,000 men and women over 12 years, Jakobsen found that people were more likely to suffer a heart attack if they cut back on saturated fat, but then replaced it with a couple hundred more calories a day from high-glycemic foods, such as white breads, muffins, potatoes and desserts. But, if the people in the study replaced saturated fat with low-glycemic foods like vegetables, fruits and whole grains, they were less likely to have a heart attack.
The key, it seems, is not limiting saturated-fat intake, but avoiding insulin-provoking foods such as refined carbs and sugars — basically what Atkins had argued. “Atkins wasn’t right about everything, but he was right about insulin,” says Taubes. “He was probably more right than anyone else at the time.”
Eat Like Your Ancestors
Krauss’s research and dietary recommendations are relatively consistent with what’s known as the Paleolithic diet — that is, ancient eating habits that some scientists consider the ideal diet.
Loren Cordain, PhD, a professor in the department of health and exercise science at Colorado State University in Fort Collins, says that ancient peoples typically ate a diet rich in lean protein, fish and vegetables, with carbohydrates coming largely from root vegetables. Even though the meats contained saturated fat and cholesterol, Paleolithic diets were devoid of any kind of processed carbohydrate and sugar, with the occasional exception of honey.
“Given our ancestral diet, meal plans fairly high in quality proteins and low in processed carbohydrates would seem to be what most people are best suited to,” says Cordain. “Our genes are virtually identical to those in people living 20,000 years ago, and we evolved eating lean proteins and vegetables. Eating a lot of processed grains and sugars is a total mismatch for our genetic heritage.”
That doesn’t mean you have to give up carbs altogether, or load up on saturated fats, to avoid a heart attack. As with most dietary issues, it’s a matter of finding a good balance. (See the sidebar, “A Bountiful Balance,” for some simple tips on healthful eating.)
Hunninghake generally concurs with this approach, but suggests that people tailor their carb intake to their weight, blood sugar and activity level. “If they’re good on all three counts, they can probably consume a little more in the way of carbs,” he says. “But if they’re overweight, have high blood sugar and are couch potatoes, they should be getting their carbs from high-fiber vegetables, not grains.”
Many people may find all this a bit disconcerting and confusing. And Krauss and Hunninghake’s advice does fly in the face of largely vegetarian diets recommended by some other physicians, including cardiovascular bigwigs like Dean Ornish, MD. In clinical trials, Ornish has had success reducing cardiovascular disease in subjects who adhere to a whole-foods, plant-based diet very low in saturated fat. But that doesn’t necessarily prove that avoiding saturated fat is a heart-healthy strategy.
“While these diets did reduce CVD, it’s not clear that reducing the saturated fat was what did it — most likely it was eating less junk food and more veggies,” says Hunninghake. “Nutrition isn’t religion. It should be based on science. And the evidence for scientific assumptions can and does change from time to time.”
The very wording of this article is denialist from its outset. The ‘perceived’ link, for example…
I notice this site has published several articles claiming that saturated fats aren’t bad and that science got it all wrong, but that simply isn’t the scientific consensus among artherosclerosis researchers. Even those researchers, that think saturated fats aren’t as bad as they have been claimed to be, almost all routinely agree that statins are effective.
Claiming that statins aren’t effective, and that cholesterol isn’t the problem with respect to heart disease, is largely inaccurate and one must necessarily ignore a large portion of the science base to come to these conclusions.
LDL cholesterol absolutely is the problem, and statins are absolutely effective. The number of people alive, who continue to walk into the doctors office 5 years after being prescribed statins, isn’t testament enough, the well understood biomolecular and cellular mechanisms involved in artherosclerosis pathogenesis demonstrate this clearly.
The other thing that has been scientifically demonstrated to be effective in reducing or halting the progression of artherosclerotic disease, includes adhering to an entirely plant based diet. This isn’t quackery, it’s the view of leading institutions such as Harvard Medical School, and is documented extensively in the peer reviewed medical literature.
And even this isn’t enough in people with severe disease, who need statins regardless.
The bottom line is, if you are genetically predisposed to a high risk of artherosclerotic disease, then increased circulating LDL concentrations are very bad news for you. Reducing them almost certainly will reduce your risk of disease substantially. For these people, eating animal products high in cholesterol, and high in saturated fat, which triggers an increase in circulating LDL concentrations, is demonstrably a very bad idea.
Also these studies ought to have controlled for the fact that even low fat skim milk increases circulating LDL concentrations, due to the influence of milk proteins. This has been demonstrated, and is documented in the literature.
So if low fat milk seems to be just as bad or not much better than whole milk, you simply cannot claim that this means saturated fat isn’t any worse than other food sources for circulating LDL concentrations. You are only comparing wholemilk to low-fat skim milk in that instance, not wholemilk to plant based milks (which would be a far more relevant comparison). Go ahead and do that research and let me know what the results are, that’s my view. Or give me the funding for it and I will do it myself.
It’s a wild leap of logic that the saturated fat lobby have seem to have fallen into far too swiftly.
Thanks for a very excellent article! It’s a great light in the darkness of “no fat, low fat” mentality. When mistakes are made (intentionally or not) it’s imperative to correct them! Thank again!
Yeah! I can eat bacon again!
Extra crispy please!
I finally found time to read this article on saturated fat and I am so glad I read it. I will for sure share this article moving forward. I recommend to my clients suffering and stuggling with heart disease to include a small amount of saturated healthy fat, such as avacado oil, coconut oil and Ghee. Thanks for your research to share and help me help my clients.
Raina D
I eat whole foods, lots of fresh vegetables and fruit, etc., as described in this article as being healthful. I eat small amounts of butter, cook with olive oil, consume no trans-fats, no sugars, and red meat once or twice a week. I am 56 years old, and I do not have high blood pressure, heart disease, or diabetes. However, I am overweight, and have pretty severe arthritis. I have been working on losing weight slowly over the last 5 years. I drink non-fat milk, and choose low fat meat and dairy products. If I were to choose the higher fat products, it would add a significant number of calories to my diet. Am I hurting myself by continuing with the lower fat products?
Hi Deborah,
I wonder if a lot of the low fat products you consume have a lot of hidden sugars added?
Plus cooking/ frying with poly and monounsaturated oils like olive oil can be problematic as these oils have a lower smoking point and thus break down and oxidise easily, negating much of the health benefits and causing them to be inflammatory. Roasting vegetables with them should ok though as well as drizzling over salads of course! 🙂
Also do you regularly consume omega 3? My mother had similar issues with arthritis and that helped a lot.
Best,
Alex
It is confusing since it directly conflicts with the China Study and Dr. Esselstyn’s clinical experience with using diet to reverse heart disease. I wish I could hear a discussion/debate of this latest research with Dr. Esselstyn and Dr.Colin Campbell and doctors who are using low fat vegan diets to reverse disease. Dr. Swank also found a low saturated stopped progression of MS and sometimes if applied early enough in the disase, reversed it. The research of Weston Price and the recommended deit from that foundation includes alot of saturated fat. What I would really like to know is how factory farmed GMO fed high saturated fat diets compare to natural diet/grass fed organic poultry and meats. Confusing, to say the least!
If you run a google search for ‘debate loren cordain t colin campbell’ you can find a copy of the debate between Loren Cordain, author of The Paleo Diet and T. Colin Campbell. It’s a very interesting read.
Not buying it on a few fronts.
Re: Paleolithic diet, there is no evidence that Paleolithic man ate meaningful quantities of meat and certainly did not consume dairy, and our bodies are not adapted to do so. Our bodies are made for eating vegetables. See Ted Talk from Dr. Christina Warinner… https://www.youtube.com/watch?v=BMOjVYgYaG8
Re: Dr. Robert Atkins: He suffered a heart attack in 2002, and after his death (from a slip and fall) his autopsy revealed that Atkins had a history of congestive heart failure and hypertension. Further, at the time of his death he weighed 258 pounds. His approach to diet causes people to gain weight, have heart disease, and cancer – as it did with him.
Re: saturated fats – it is clear that your body needs fat intake, and between 10-15% of your calories should come from fat. But animal fats have many issues with associated with them – e.g. they lead to an increase in insulin like growth factor 1, which is implicated as a high risk cancer causing agent. Even worse, when they come from animals, they are blended with hormones and antibiotics (fed to the animals) that are bad for you. Further, the meats themselves have other chemicals that are bad for you – e.g. carnitine found in red meat leads to atherosclerosis; charring of meat leads to production of nitrosamines that can lead to cancer of the stomach. In fact, a diet high in animal protein increases the risk of cancer 4x-fold.
Re: New comprehensive studies suggesting saturated fats are healthy – Dr. Walter Millet, chair of the Department of Nutrition at Harvard School of Public Health, warns that the studies contain multiple serious errors and omissions, that the conclusions are misleading and should be disregarded.
However, a diet rich in a variety and high quantity of vegetables is healthy. To maximize health, animal product consumption should be limited – the vast majority of our calories should come from leafy vegetables and vibrantly colored fruits.
Selma, it might interest you to note that Campbell’s book, “The China Study,” presents VERY different conclusions from what the actual study (full title: “Diet, Life-style and Mortality in China”) that was published in professional journals concluded, and that many have shown that Campbell, in his book, cherry picked data and used incorrect statistical principles to “prove” his assertions. (Also, contrary to popular belief, Campbell was just one of several key researchers involved in the actual study. He was not the lead or principal scientist, and some of the co-authors of the study came to vastly different conclusions than the one Campbell espouses in his mass-market book.) In truth, Campbell was a vegan activist before he ever wrote his book, and he didn’t draw his conclusions from the data, he came up with his conclusions based on personal bias and then manipulated the data to fit his conclusions.
More:
http://www.proteinpower.com/drmike/cancer/the-china-study-vs-the-china-study/
(Also follow the links within this article for more information on why Campbell’s book isn’t really worth the paper on which it’s written. He’s simply a bad scientist who has most people fooled.)
(If you’re mathematically/statistically inclined, better explanations as to why the China Study is basically worthless):
http://rawfoodsos.com/2010/07/07/the-china-study-fact-or-fallac/
http://rawfoodsos.com/2010/07/07/the-china-study-fact-or-fallac/
(Very long — there’s a LOT to refute.)
Selma,
I know it has been a while so maybe you won’t see my response. I wanted to address a component of your question that I believe went un-answered but is vital. Unfortunately, the article itself only made a passing reference to grass-fed animal products. This is a major issue for me personally and is all too often over-looked or on the periphary of the conversation. Simply put, cows are built to eat grass. When they are fed starchy corn and soy diets, they get sick. This is why their diet includes antibiotics. I say includes antibiotics because “farmer” no longer waits till animal gets sick, “farmer” feeds them antibiotics as part of the animal’s diet. Forget the myriad problems all of this creates, the resulting meat contains an omega 3 to omega 6 fatty acid profile that is way out of wack. http://onlygrassfed.com/health-benefits.html. Also, pasture animals and their dairy or meat products are rich in conjugated lineolic acid. Conventional animals, not so much.
That is quite a surprising study. Glad you’re sharing break through findings especially when it goes against what we’ve always thought.
I must say this is one of the best articles I have seen in regard to Saturated Fat. There is a lot of confusion that continues because of total lack of understanding how the body functions–the pharmaceutical companies have to much to lose. Go to http://www.drulgessdoctor.com. Dr. Bob De Maria
Great article! It is disappointing that in light of all of the evidence, so many people are still under the assumption that eating fat is bad for their health. The tide is turning and I really like Taubes’ new book (loved Good Calories, Bad Calories as well) since it is more user-friendly to the layperson. I’m on board with his agenda that we can’t sit idly by waiting another 50 years for people to get the message that they need to eat plenty of good fat and stop eating sugar and a lot of carbs.
The misperception that saturated fat is a killer on par with a loaded gun pointed at your heart is something my family and I have had to battle a lot when defending our decision to cut out all processed food and eat only whole dairy straight from the cow, pastured meats straight from the farmer and vegetables straight from our garden! Some people (mostly those who have spent years forcing themselves to eat no fat and low fat processed foods) are actually afraid to eat at our house because we don’t buy anything that has been modified to be low fat. Thanks for this article! Work like this is the reason I always refer people to your magazine!
Finally an article that not only dismisses the low fat = good health dogma but also doesn’t recommend choosing unsaturated fats over saturated fats. Chemically, saturated means stable – nothing else – and when it comes to fat in your cell membranes or fat in cooking, chemical stability is all important. The switch is coming back to stable, saturated fat!
should have called this article a big missed steak!