How Fats Help You Stay Lean, Plus 9 Other Need-to-Know Fat Facts

Last Update: May 13, 2024

Medically Review by Dr. Mark Hyman

“Everyone seems to be talking about fat these days—I’ve heard that fat is somehow good now, and can help with weight loss and disease prevention. How can that be true, when for decades we all were told that fat was the bad guy?”

That’s a recent question I received and it came at the perfect time. I’ve just finished writing my new book Eat Fat, Get Thin, which hits bookstore shelves on February 23. I wrote this book because almost everyone I know—doctors, patients, and eaters alike—are all confused about fat and still hold on to myths and misinformation that prevents them from taking advantage of the latest science to lose weight and get healthy [1].

You’re likely familiar with many of them: Fat makes us gain weight, contributes to heart disease, and leads to “diabesity.” Saturated fat is bad—vegetable oils are good. I could go on, but I think you know what I’m talking about.

None of these beliefs about fat are true. In my latest book, I combined the latest research with my several decades of empirical evidence working with patients to prove what I’ve long discovered: The right fats can help you become lean, healthy, and vibrant [2].

Fat is one of the body’s most basic building blocks. The average person is made up of between 15 and 30 percent fat! Yet for decades, we’ve unfairly demonized dietary fat, diligently followed a low-fat diet that almost always equates into a high-sugar and high-refined carb diet that may contribute to insulin resistance, obesity, heart disease, type 2 diabetes, and numerous other problems [3].

Simply put: Sugar, not fat, is the real villain that steals our health and sabotages our waistlines [4].

With Eat Fat, Get Thin, I’m determined to separate fat from fiction by giving you the skinny on fats: what to eat and how to use dietary fats to regain your health and ideal body weight.

I’m going to blow up the myths about dietary fat and show you how this still-maligned macronutrient can help you become lean and healthy.

For now, let’s look at 10 take-home fat facts.

1. Sugar, not fat, makes you fat.

The average American eats 152 pounds of sugar and 146 pounds of flour (which converts into sugar) every year [5]. That’s nearly a pound of sugar and flour combined every day! More sugar means your cells become numb to insulin’s “call.” Your body pumps out more and more insulin to pull your blood sugar levels back down [6]. You can’t burn all the sugar you eat. Inevitably, your body stores it as fat, creating insulin resistance and overall metabolic havoc among other mayhem [7].

2. Dietary fat is more complex than sugar.

There are some 257 names for sugar, but despite very minor variations, sugar is sugar is sugar—it all wreaks havoc on your health [8]. Fat is more complex. We have saturated, monounsaturated, polyunsaturated, and even trans fats, not to mention subcategories within each group. Some fats are good; others neutral; and yes, a few are bad [9].

3. Low-fat diets tend to be heart-unhealthy and high in sugar.

When people eat less fat, they tend to eat more starch or sugar instead, and this actually increases their levels of the small, dense cholesterol that causes heart attacks [10]. In fact, studies show 75 percent of people who end up in the emergency room with a heart attack have normal overall cholesterol levels [11]. But what they do have is pre-diabetes or type 2 diabetes.

4. Saturated fat is not your enemy.

A review of all the research on saturated fat published in the American Journal of Clinical Nutrition found no correlation between saturated fat and heart disease [12]. As with all fats, quality becomes key here. The fats in a fast-food bacon cheeseburger will have an entirely different effect than coconut oil. Let’s stop classifying it all as the same.

5. Some fats are unhealthy.

They include trans fat and inflammatory vegetable oils. Unfortunately, these fats have increased in our diet as they make us fatter and contribute to inflammation, which plays a role in nearly every chronic disease on the planet [13].

6. Everyone benefits from more omega-3s.

About 99 percent of Americans are deficient in these critical fats [14]. Ideal ways to get them include eating wild or sustainably raised cold-water fish (at least two servings weekly), buying omega-3 rich eggs, and taking an omega-3 supplement twice a day with breakfast and dinner (one that contains 500 to 1,000 milligrams of omega-3 fats, a ratio of roughly 300 EPA to 200 DHA, is ideal). You’ll find several quality professional omega 3 supplements in my store.

7. Eating fat can make you lean.

Healthy cell walls made from high-quality fats are better able to metabolize insulin, which keeps blood sugar regulated [15]. Without proper blood-sugar control, the body stores fat for a rainy day. The right fats increase fat burning, cut your hunger, and reduce fat storage, and help you lose weight—while eating excess sugar and the wrong types of fat makes you fat [16].

8. Good fats can heal.

I have many diabetic patients whose health improves when I get them on diet that’s higher in fat. I had one patient with high cholesterol who could not lose weight, so I bumped up her healthy fat content to 70 percent. (I don’t recommend this for most patients; hers was an extreme case.) Her cholesterol plummeting from 300 to 190, her triglycerides dropped 200 points, and she lost 20 stubborn pounds that she couldn’t ever lose before!

9. Your brain is about 60 percent fat.

Of that percentage, the biggest portion comes from the omega-3 fat called docosahexaenoic acid (DHA) [17]. Your brain needs DHA to spark communication between cells. Easy access to high-quality fat boosts cognition, happiness, learning, and memory. In contrast, studies link a deficiency of omega-3 fatty acids to depression, anxiety, bipolar disorder, and schizophrenia [18].

10. Your body will tell you whether or not you’re getting enough quality fat.

The higher-quality the fat, the better your body will function [19]. That’s because the body uses the fat you eat to build cell walls. You have more than 10 trillion cells in your body, and every single one of them needs high-quality fat. How do you know if your cells are getting the fats they need? Your body sends signals when it’s not getting enough good fats, including:

  • Dry, itchy, scaling, or flaking skin
  • Soft, cracked, or brittle nails
  • Hard earwax
  • Tiny bumps on the backs of your arms or torso
  • Achy, stiff joints

I eat fat with every meal, and I’ve never felt better. The right fats can improve your mood, skin, hair, and nails, while protecting you against type 2 diabetes, dementia, cancer, and much more [20].

My favorite sources of fat include:

  • Avocados
  • Nuts: walnuts, almonds, pecans, macadamia nuts, but not peanuts (One study showed a handful of nuts a day reduced death from all causes by 20 percent.)
  • Seeds: pumpkin, sesame, chia, hemp
  • Fatty fish, including sardines, mackerel, herring, and wild salmon that are rich in omega-3 fats
  • Extra virgin olive oil (A large study showed that those who consumed 1 liter a week reduced heart attacks by 30 percent.)
  • Grass-fed or sustainably raised animal products (I recommend the Environmental Working Group’s Meat Eater’s Guide to eating high-quality animal products that are good for you and the planet).
  • Extra virgin coconut butter, a great plant-based source of saturated fat that has many benefits.  (It fuels your mitochondria, is anti-inflammatory, and  doesn’t cause problems with your cholesterol.  In fact, it may help resolve them. )

Want to learn more? Check out my Q&A video, in which I answer questions about fat, including:

  • If it’s not fat, what is the true cause of heart disease, diabetes, and disease?
  • How can we differentiate between good and bad fat?
  • Is butter really good for you?
  • And how did we get into this big, “fat” mess?

Watch the video here.

Photo credit: Paul Delmont

Share this article

Dr. Mark Hyman

Mark Hyman, MD, believes that we all deserve a life of vitality—and that we have the potential to create it for ourselves. That’s why he is dedicated to tackling the root causes of chronic disease by harnessing the power of Functional Medicine to transform healthcare. Dr. Hyman is a practicing family physician, an eight-time #1 New York Times bestselling author, and an internationally recognized leader, speaker, educator, and advocate in his field. He is the Director the Cleveland Clinic Center for Functional Medicine. He is also the founder and medical director of The UltraWellness Center, chairman of the board of the Institute for Functional Medicine, a medical editor of The Huffington Post, and was a regular medical contributor on many television shows including CBS This Morning, Today Show, CNN, and The View, Katie and The Dr. Oz Show.

Download the app for easy shopping on the go

By providing your mobile number, you agree to receive marketing text messages from Thrive Market. Consent not a condition to purchase. Msg & data rates apply. Msg frequency varies. Reply HELP for help and STOP to cancel.

If you are visually-impaired and having difficulty with our website, call us at 1‑855‑997‑2315

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

© Thrive Market 2024 All rights reserved.