What Doctors Need to Know About Fat

Headshot Hyman 2013As physicians, many of us were trained to tell our patients that eating cholesterol and fat – especially saturated fat– causes heart attacks, and that taking statin drugs provide a powerful way to reduce your risk of getting them. But is this really true?

One of the biggest refuse-to-die myths is that dietary and cholesterol levels are the enemy, and a high-fat diet causes heart attacks. Yet study after study shows no connection between total fat, saturated fat, or dietary cholesterol and heart disease.

One review of 72 studies comprising almost 600,000 people found no link between total or saturated fat and heart disease, but they did find that trans-fats were clearly harmful and that omega-3 fats were beneficial.

What we don’t hear enough about are the many studies that show that most people who have heart attacks actually have normal cholesterol levels. Because we have statins and other drugs that lower cholesterol, it’s easy to ignore prevention and just lean on these tools when situations turn dire. What we need to focus on instead, however, is what we can do to reduce the risk for heart attack.

One large study looked at 541 hospitals with 136,905 admissions for heart attacks. Altogether, researchers accounted for 59 percent of all heart attacks in America that year.

Interestingly, none of the patients who had heart attacks had high LDL or elevated total cholesterol. In fact, 75 percent of those people had “normal” LDL cholesterol, with 50 percent having optimal LDL levels. So much for the high LDL contributing to heart attacks.

Here’s where it gets interesting. Only ten percent of the participants had levels of HDL (“good”) cholesterol over 60. This means that 90 percent of these patients who suffered a heart attack had HDL levels under 60. Low HDL is a big red flag for pre-diabetes – or what I call diabesity. And we now believe that low HDL is the real driver of most heart attacks and heart disease.

Indeed, researchers in this study found most of these patients had metabolic syndrome, pre-diabetes.

I have seen this over and over in my practice for several decades. Fat and dietary cholesterol are not the culprits. It’s sugar and refined carbs that contribute to diabesity, heart disease, and so many other problems.

The 2015 U.S. Dietary Guidelines Advisory Committee reviewed all the research over 40 years and told us to stop worrying about dietary cholesterol, arguing it is “not a nutrient of concern.” They also finally lifted any recommendations to restrict dietary fat. This, after 35 years of a steady diet of low-fat recommendations! This was buried in the report but is huge news.

I recently interviewed one of the world’s leading cholesterol experts, Dr. Ronald Krauss. He told me in the 1980s, when low-fat recommendations were in their heyday, he performed a study taking people with normal cholesterol and feeding them a low-fat, high-carb diet, which experts considered healthy at the time.

Dr. Krauss was shocked at what happened. This supposedly healthy low-fat diet changed healthy cholesterol profiles into heart attack-prone profiles, with high triglycerides, low HDL, and small LDL particles. Researchers were stunned.

What we now know matters most is the type of fat you eat, not the amount. Trans-fats and refined vegetable oils promote abnormal cholesterol profiles; whereas, omega 3 oils from fish and monounsaturated fats found in nuts and olive oil can actually improve the type and quantity of your cholesterol.

Trans and damaged fats are unhealthy, but the biggest culprit of abnormal cholesterol levels is not fat at all. It is sugar in all its many forms.

The sugar we consume converts to abnormal blood cholesterol and belly fat. The biggest culprit of all is high-fructose corn syrup (HFCS) found in soda, juices, and in most processed foods. That’s what causes cholesterol issues in most people, not saturated or total fat.

So, why are we all obsessed with total cholesterol and LDL cholesterol when we know they aren’t the primary culprits for heart attacks? Because a multibillion dollar drug industry exists behind the number-one best-selling class of drugs on the market: Statins.

Believing that having a low LDL is the best way to prevent heart disease, we physicians often prescribe medications like statins to keep those levels low. But perhaps it’s time to start thinking a little differently about this. What we’re learning about fats (and sugars) are one more argument for intervening earlier with patients – and for paying attention to not just research on drugs, but the latest information on diet, too.

Mark Hyman, MD, is founder and Medical Director of The UltraWellness Center in Lenox, Massachusetts. A six-time #1 New York Times bestselling author, Dr. Hyman is Chairman of the Institute for Functional Medicine, medical editor at the Huffington Post, a member of the Medical Advisory Board at both The Doctor Oz Show and HealthCorps, and a volunteer for Partners in Health. He has worked with congress and the surgeon general on issues related to prevention, and currently serves on the President’s Advisory Group on Prevention, Health Promotion and Integrative and Public Health. Among his public appearances, Dr. Hyman has spoken on the stages of The World Economic Forum and TEDMED (his talk at TEDMED 2012 was ranked in the top 10 TED speeches). His latest book, Eat Fat, Get Thin, was just released.

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  1. I remember seeing another Doctor posting that may also be a key reason for heart attacks. Low magnesium and D3 levels could cause heart attacks as welll. If I am correct magnesium and D3 keep the calcium directed to our bones and away from our heart. The doctor said they give hear attack patients an IV full of magnesium after or during a heart attack. I cannot remember the doctor or the website that this was posted on. I think this ties into the post above. I am not a doctor so I would like feedback on my post.

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