Why You Need Healthy Fats For Your Brain, Hormone & Immune Health

Low-Fat Diets Are No Good Dr. Will Cole

Brain disorders have reached epidemic proportions. Anxiety, brain fog, fatigue, depression, ADD, autism, Alzheimer’s Parkinson’s, and multiple sclerosis are just the short list of conditions affecting nearly everyone in some way. Why is this happening? What are we doing in our society that could have triggered such a disabling epidemic – one that threatens so many livelihoods and has drastically reduced quality of life for so many?

While there are many complex reasons for the decline in brain health in the modern world, I believe that one of the primary culprits may be something you are doing every day because you believe it is good for you: Eating a low-fat diet.


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The Fallout From The Fear of Fat

For decades now, fat and cholesterol have been considered health food villains and largely demonized in the American diet. Since the latter part of the 20th century, we’ve been told by doctors, dietitians, and even the U.S. government, that fat would clog our arteries, cause weight gain, and even kill us with heart attacks. No wonder so many have chosen to drastically reduce the fat in their diets!

This belief remains mostly intact, but fortunately, its days are numbered as science has begun to see the light and uncover the real truth about fat. One 2014 study (1) in the medical journal Neurology found that, contrary to popular belief, there might actually be no association between high total cholesterol and stroke risk. In fact, other research has shown (2) that low cholesterol may actually increase the likelihood of death from all causes. At the same time, some of the many side effects of statins – cholesterol-lowering drugs – include memory loss and brain dysfunction.

The truth is that as the fattiest organ in your body, your brain is composed of 60% (3) fat, and as much as 25% (4) of your body’s cholesterol is found in the brain. So why would we deprive our brains of the very nutrient that it's made of?

Consuming cholesterol and fat is critical to the health and function of the brain. As it turns out, for all our good intentions, as a society we have been starving our brains of their basic building blocks.

What’s The Best Brain Fuel: Sugar or Fat?

Today, the standard Western diet centers around many forms of sugar. From the refined carbohydrates that mostly make up junk foods (from fast food, cookies, and candy) to breads, pastas, fruit, and juices, sugar makes up most of what we’re eating, and since it’s fat-free, somehow this dietary habit has gotten a pass.

Many of us were taught that the brain runs on glucose, so all these simple carbs were necessary to fuel the brain. But is sugar really the best form of energy for your brain? One 2013 study (5) found that higher blood sugars in non-diabetics decreased function in areas of the brain typically affected by Alzheimer’s disease (AD). This and similar research contribute to why AD is now often referred to in the medical literature as “type 3 diabetes.”

On the other hand, a ketogenic diet – where fat, not sugar, is the primary source of energy – has been shown (6) to do some remarkable things for brain health. Healthy fats are a slow, sustainable form of energy, unlike the sugary roller coaster many find themselves on when their diets are primarily carb-based. If you look at the human being from infancy, you can see that biology knows best: as babies, we were all born relying on fat in the form of high-fat breast milk for brain development (7) and energy.

Bottom line: Brains that work optimally require a lot of energy, and from a biology (3) and evolutionary (8) perspective, the most sustainable form of energy for optimal brain health is good fats.

What Now? 3 Ways to Better Your Brain Health

1. Ask your doctor about labs

There are many great lab tests that I recommend to help determine if your brain is healthy or not. For example, look into having homocysteine and fasting insulin tests done. These labs can give you insight into your specific case, as well as where to go from there.

2. Feed your brain good fat

Changing the way you view fat and cholesterol can be overwhelming, especially if you’ve spent years of your life avoiding them. Start by educating yourself on the best sources of fats for your brain, including which fats are most effective at decreasing inflammation, which is linked to just about every brain problem.

For example, arachidonic and docosahexaenoic acids are two forms of fat that play an important role (9) in brain health. The most bioavailable sources for these brain foods are grass-fed meats and wild-caught fish. Coconut oil is also a wonderful plant-based source for your brain: MCTs (medium chain triglycerides) found in coconut oil has been shown (10) to improve cognitive function. Monounsaturated fats like extra virgin olive oil and avocados are also beneficial to your brain.

Be sure to start adding in fat slowly. After years of low-fat diets, it’ll take your system a while to adjust to eating healthy fats.

3. Consider personalized functional medicine care

Functional medicine practitioners know that what works for one person may not work for another, but in general, adding in more healthy fats is a wise move. But how much is right for you? The ideal ratio of fats, carbohydrates, and proteins should be determined on an individual basis. Some people don’t do well on ketogenic diets, for example, and targeted brain natural medicines depend on your unique needs. A functional medicine practitioner can help you figure it out. Check out our health consultation to get started with functional medicine.

The Healthiest Fat Choices

Use saturated fat for high heat cooking.

These fats can tolerate higher heat temperatures without becoming oxidized. Buy organic, unrefined forms, from grass-fed sources if animal based, whenever possible:

  • Coconut oil
  • Palm oil
  • Animal fat (from beef, lamb, chicken, or pork)
  • Butter
  • Ghee

Use unsaturated fat for dressings and dips.

Unsaturated fats can be easily damaged and oxidized when heated, but are supremely healthy in their organic, extra virgin, cold-pressed form:

  • Avocado oil
  • Macadamia nut oil
  • Olive oil
  • Sesame oil
  • Walnut oil

Healthful whole food fats:

Aside from added fats, some whole foods are naturally high in fat, and these can be excellent additions to your diet when they are organic and come from pasture-raised or grass-fed sources:

  • Whole eggs
  • Higher fat meat like beef and dark-meat poultry
  • Seafood, like shellfish and cold-water fatty fish
  • Full-fat dairy products, especially raw or fermented
  • Raw nuts and seeds

Never choose these:

I never recommend eating industrially produced fats and refined seed oils due to their highly processed and highly inflammatory nature. These are never good choices in any circumstance, and will also oxidize easily with light, air, or heat exposure:

  • Margarine or “buttery spreads”
  • Canola oil
  • Corn oil
  • Grapeseed oil
  • Rice bran oil
  • Safflower oil
  • Soybean oil
  • Sunflower oil
  • Vegetable oil
  • Anything that has the term “partially hydrogenated” in the ingredients

Bottom line? Stop fearing fat! If you make smart choices, fat can help you feel great and prime your hormones and brain for optimal functioning.

As one of the first functional medicine telehealth clinics in the world, we provide webcam health consultations for people around the globe. 

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  1. Schilling S, Tzourio C, Dufouil C, et al. Plasma lipids and cerebral small vessel disease. Neurology. 2014;83(20):1844‐1852. doi:10.1212/WNL.0000000000000980
  2. Prof Dr. Irwin J Schatz, MD, Prof Kamal Masaki, MD, Katsuhiko Yano, MD, Randi Chen, MS, Prof Beatriz L Rodriguez, MD, Prof J David Curb, MD Cholesterol and all-cause mortality in elderly people from the Honolulu Heart Program: a cohort study Volume 358, Issue 9279, P351-355, August 04, 2001. doi:10.1016/S0140-6736(01)05553-2
  3. Chang CY, Ke DS, Chen JY. Essential fatty acids and human brain. Acta Neurol Taiwan. 2009;18(4):231‐241.
  4. Ingemar Björkhem and Steve Meaney Brain Cholesterol: Long Secret Life Behind a Barrier Arteriosclerosis, Thrombosis, and Vascular Biology 5 February 2004. https://doi.org/10.1161/01.ATV.0000120374.59826.1b
  5. Burns CM, Chen K, Kaszniak AW, et al. Higher serum glucose levels are associated with cerebral hypometabolism in Alzheimer regions. Neurology. 2013;80(17):1557‐1564. doi:10.1212/WNL.0b013e31828f17de
  6. Gasior M, Rogawski MA, Hartman AL. Neuroprotective and disease-modifying effects of the ketogenic diet. Behav Pharmacol. 2006;17(5-6):431‐439. doi:10.1097/00008877-200609000-00009
  7. Medina & Tabernero J. Neuroscience.Res. (2005) 79:2-10
  8. Leonard WR, Snodgrass JJ, Robertson ML. Evolutionary Perspectives on Fat Ingestion and Metabolism in Humans. In: Montmayeur JP, le Coutre J, editors. Fat Detection: Taste, Texture, and Post Ingestive Effects. Boca Raton (FL): CRC Press/Taylor & Francis; 2010. Chapter 1. Available from: https://www.ncbi.nlm.nih.gov/books/NBK53561/
  9. Kiso Y. Pharmacology in health foods: effects of arachidonic acid and docosahexaenoic acid on the age-related decline in brain and cardiovascular system function. J Pharmacol Sci. 2011;115(4):471‐475. doi:10.1254/jphs.10r39fm
  10. Reger MA, Henderson ST, Hale C, et al. Effects of beta-hydroxybutyrate on cognition in memory-impaired adults. Neurobiol Aging. 2004;25(3):311‐314. doi:10.1016/S0197-4580(03)00087-3

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Dr. Will Cole, DNM, IFMCP, DC is a leading functional medicine expert who consults people around the globe, starting one of the first functional medicine telehealth centers in the world. Named one of the top 50 functional and integrative doctors in the nation, Dr. Will Cole provides a functional medicine approach for thyroid issues, autoimmune conditions, hormonal imbalances, digestive disorders, and brain problems. He is the host of the popular The Art Of Being Well podcast and the New York Times bestselling author of Intuitive Fasting, Ketotarian, The Inflammation Spectrum and the brand new book Gut Feelings: Healing the Shame-Fueled Relationship Between What You Eat and How You Feel.

Gut Feelings Dr. Will Cole 6

Gut Feelings

Healing The Shame-Fueled Relationship
Between What You Eat And How You Feel