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General Health

Don’t Fear Fat, According to a Functional Medicine Expert

Confused about which fats to eat and how much? Dr. Mark Hyman clears up the controversy.

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It’s been a few years since the nutrition world has done a 180 on the low-fat craze, and here at Clean Eating, we’ve been long advocating to ditch the non-fat and low-fat items in favor of incorporating healthy fats into your diet. But the anti-fat movement – and the confusion around which fats to choose and how much – still runs deep. 

We reached out to esteemed functional medicine doctor, Mark Hyman, MD, founder and Medical Director of The Ultrawellness Center and author of The Pegan Diet: 21 Practical Principles for Reclaiming Your Health in a Nutritionally Confusing World (Little, Brown and Company) to help set the record straight on dietary fats.

“Fats are critical for our health. Our cells need fat, our brains need fat. We don’t need to fear fat,” says Dr. Hyman, who recommends three to five servings of fat per day. You’ll find him drizzling olive oil on his salads or veggies, adding avocado to his smoothies or snacking on nuts and seeds.  

Individualized medicine

But like anything in the nutrition world, which types of fats to eat can be unique to the individual. “Unfortunately, fat is a little complicated,” explains Dr. Hyman. “Not everyone should be eating the same amount of fat, especially saturated fat. You have to find what works for you.” 

Why? Dr. Hyman explains that some people – including himself – are what he calls “lean mass hyper responders.” While these individuals may be athletic and lean, their lipids (specifically, their cholesterol and triglycerides) may become abnormal if they eat too much saturated fat from foods like coconut oil, red meat and butter. On the other side of the coin, Dr. Hyman has seen some patients who are overweight and their lipids actually normalize on a high-fat, low-carbohydrate diet. So what should you do? “Find what works for you and start by eating real, whole food,” says Dr. Hyman. 

Testing can offer clarity

There is genetic testing available that can help you figure out the best path for your own health when it comes to saturated fat consumption, and Dr. Hyman recommends this as a valuable tool for those with a family history of heart disease or Alzheimer’s disease. (Ask your doctor for testing for the APOE4 gene.)

Another test that might be helpful to look into, according to Dr. Hyman is the NMR Lipid Panel or the Cardio IQ Test (from LabCorp or Quest Diagnostics, respectively), which provide more information on the quality of your cholesterol levels than simply testing total cholesterol. In fact, Dr. Hyman goes so far as to urge you to insist on these tests. “Total cholesterol alone doesn’t provide the whole picture and the particle size and particle number is far more indicative of health than other tests that are outdated. You want to see results that show lots of safe, light, fluffy, big cholesterol particles. You do not want to see small, dense, artery-damaging cholesterol particles.” he says. 

The doc’s faves

While there might be some controversy over high amounts of saturated fats, other fats like olive oil, avocado, and nuts and seeds are suitable for just about everyone, Dr. Hyman says. 

In your own kitchen, Dr. Hyman recommends cutting out all refined oils. He suggests using extra-virgin olive oil for raw and low-temperature uses. For high-temperature cooking, he suggests avocado oil or ghee. Coconut oil also can also withstand heat and is great for baking and sautéeing. 

What are the top oils Dr. Hyman uses regularly in his own kitchen? “I always have olive oil, avocado oil, and I use a little bit of MCT oil every now and then,” he says. 

Dr. Hyman’s list of fats to include and fats to avoid

Eat Avoid or Limit
Organic extra virgin olive oil Soybean oil
Organic avocado oil Canola oil 
Walnut oil Corn oil
Almond oil Safflower oil
Macadamia oil Sunflower oil
Unrefined sesame oil Peanut oil
Tahini (sesame paste) Vegetable oil, grape-seed oil
Flax oil Vegetable shortening 
Hemp oil Margarine and butter substitutes
Avocado, olives and other plant sources of fat Anything that says “hydrogenated”
Nuts and seeds 
Butter from pastured, grass-fed cows or goats
Grass-fed ghee
Organic, humanely raised tallow, lard, duck fat, or chicken fat
Coconut oil or MCT oil (medium-chain triglycerides)
Sustainable palm oil (look for certified sustainable palm oil)

Excerpted from THE PEGAN DIET. Copyright © 2021 by Hyman Enterprises, LLC. Used with permission of Little, Brown Spark, an imprint of Little, Brown and Company. New York, NY. All rights reserved.