What is a High-Fat Diet: Is it Healthy and Safe?

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A plate with high fat foods like avocado and bacon

What is a high-fat diet? Is a high-fat diet healthy and safe? To answer these questions we need to dig a bit into the past. Until recently, the health-conscious consumer has been guided by the same outlines prescribed by the National Food Pyramid since the 1970s.

The work of Ancel Keys and what became known as the Seven Countries Study was hugely influential to what we understood was good for us and what was not. The key was the discovering a correlation between heart disease and the amount of saturated fat present in the diet. Bingo! Suddenly, the name of the health game took on a decisive theme: low fat.

Since then, we’ve heard the adage “the fat you eat is the fat you wear” and for decades, folk took this as gospel. Unfortunately, far too many also took that false next step into processed foods, as thousands of prepared low-fat food options flooded supermarkets to keep up with the demand for low fat at all costs… even when it meant high sugar and low nutrition to boot.

No wonder the obesity epidemic skyrocketed. Today, with the paleo, ancestral and low-carb diets making a come-back, and gaining more exposure over the last decade, the conventional wisdom around low fat eating came into question.

So What is Considered a High-Fat Diet?

A high fat diet or HFD is defined as the ratio of your macro-nutrients (fat, carbohydrate, protein) and so, high fat is considered above 40-45% of your daily caloric intake. Anything between 20% to 40% is considered moderate, and if your daily fat intake is below 20%, then you’re sitting squarely in the low-fat zone.

Despite a growing number of studies that show the benefits and health giving properties of including more good fats in the diet, it’s still a controversial subject for some. More and more experts are professing the possibility that high-fat diets may not be as bad for arteries as they once thought. Even still, lines are drawn in the dirt very decisively.

But as we’ve said before here at IPE “for every PhD there is an equal and opposite PhD”. For every study saying, x there are just as many studies proclaiming y – and they both make sense. It begs the question whether there really is anything new in nutrition worth talking about. So what to do?

In an effort to support your exploration process here are a few points to consider.

Fatty Foods and Brain Benefits

Our brains demand a lot from us – particularly when it comes to energy. Even though it only takes up 2% of our body weight, our brains require 20% of our total energy. Consider for a moment the fact that the brain and nervous systems is composed of nearly 80% fat. 50% of which is saturated.

It makes sense that good fats help us maintain healthy brain function. And there happens to be a few that help in particular. Healthy high-fat foods are high in omega-3 fatty acids and have been shown to assist the body in the production of the myelin that insulates brain and spinal cord cells.

Essential fatty acids like EPA, DHA, and ALA, all work together to improve an individual’s cardiovascular profile, increase their lifespan, decrease their risk of heart disease, and have even been proven to decrease the risk of cancer.

Fat and Hormones

Cholesterol, while much maligned and misunderstood is actually very important to our health. In fact, it’s what provides structure to every cell membrane in our body, and is considered essential for the establishment of proper membrane permeability and fluidity. In addition, it’s responsible for the formation of all our hormones: including estrogen, testosterone, and cortisol – the stress hormone), as well as bile acids, Vitamin D (which works like a hormone) and DHEA, which is a very important endogenous steroid hormone that’s been shown to protect against obesity.

Fat Soluble Vitamins

Vitamins – those micronutrients your body needs in certain amounts to complete a variety of essential task in the body, come largely in two forms: water-soluble (like vitamins B and C for example) and fat-soluble (such as: A, D, E, and K). Water-soluble vitamins are those that require regular replacement in the body, as they are used and excreted on a daily basis.

Fat-soluble vitamins on the other had, are stored in the liver and other fatty tissues, and so stay in the body much longer. The controversy stems from the fact that fat-soluble vitamins are often said to be most easily assimilated from animal sources, but when supplemented can be very toxic in high amounts.

For this reason, the low fat option is to source them as best you can from the plant kingdom in their precursory form. The plant-based antecedent to vitamin A, for example, is called beta-carotene and is available in many different types of fruit and vegetables. But certain individuals struggle converting Vitamin A – retinol from the beta-carotene.

Vitamin D3 is essential for how we uptake calcium and phosphorus, it helps us build bones, teeth, boosts our immune system and regulates growth. Our body can make it with good sun exposure, but that’s hard to do with sunscreen on, and it’s also hard to come by in the winter months in much of the northern hemisphere.

Good sources of Vitamin D are raw diary and fatty-oily fish like salmon, herring and sardines. It’s also fortified in much of the milk in our country. But over-supplementing with non-food based sources of D can cause damage to the liver and kidneys.

The Type of Fat Matters

Much of our medical culture has begun railing against carbohydrates as the villain in the same way fats were being forbidden 40 years ago. People count carbs instead of fat grams. They avoid grains and starches the way they used to avoid avocado and butter. But here’s where the issue of quality enters the picture.

Despite their differences, there’s one thing that the low-fat and high fat camps seem to be in agreement on and that’s their all-around thumbs down to seed and vegetable oils (polyunsaturated fats or PUFAs) like canola, safflower, soy, corn, etc. which are being proven as harmful to the body.  They’re highly oxidized, contribute to aging, make for flimsy arteries, promote dangerous body fat, and damage the delicate enzymes necessary for protein absorption.

Trans fats, or partially hydrogenated oils, are another type of fat to be avoided, as they have been chemically altered such that a liquid fat becomes a solid at room temperature. Think about the physical qualities olive oil versus margarine and you’ll get the idea.

That’s where the similarities end however.

For the high fat camp is still in favor (of course) of including dietary fat from naturally occurring and traditional sources, like: olive oil, coconut oil, avocado, nuts and animal fats such as butter, ghee, cream, tallow, lard etc. Those in the low fat camp have found benefit from reducing animal fats and processed oils (even olive oil) when it comes to disease mitigation and management without medications, particularly genetic heart disease, obesity, chronic high cholesterol and arteriosclerosis.

The high fat camp extols the power of fat (especially animal fat) to restores good digestion and elimination, as well as a great way to burn excess weight, and maintain a healthy amount of cholesterol in the body for cellular health.

The low-fat camp points out that the body creates all the cholesterol it needs, that whole food, plant based sources of these fats are the most gentle on the body, and extol the benefits of starch in helping to restores good digestion and elimination, as well as a great way to achieve satiation and burn excess weight.

Is High-Fat Diet Healthy and Safe?

There certainly seems to be enough science to back up either side. But the truth is: it all depends on where you are in your journey as an Eater. This is part of the very important work that we engage our students in as part of our Eating Psychology Coach Certification Training. We understand that everyone has a different Nutritional Story at work in their life.

So the question is: Is a high-fat diet healthy and safe for YOU?

If you’ve been on the low-fat train for awhile (or decades) and you’re struggling with memory, your skin is dry, you’re constipated, you always feel hungry, can’t seem to put on weight, or your hormones are a mess, then it may be worthwhile to experiment with the amount of fat in you diet.

If you feel sluggish, or dull, or you’ve been doing the high-fat diet too long, and start having dreams of steamed vegetables, be open to cutting back and letting your body lead the way. If you’re looking to lose weight, you might very well lose it by going low-fat. But the scales tip the other direction as well, and a high fat diet has been shown to lean out the physique as well.

The reality is that when you cut fat, this will eventually force your body to burn fat stores, including all the toxins stored in your fatty tissues. This is a benefit to many, no doubt, but bear in mind that when you lose body fat, you are burning it.

In other words, you are metabolizing saturated fat through your system, in the same way you might from external sources, and yet no harm comes to you. It just so happens that the saturated fat you’re “digesting” is your own.

But maybe you’ve already tried every way of eating under the sun, and nothing has shifted. Maybe it’s time to get real about weight-loss. Maybe it’s time to ask if the heath stress you’re experiencing really exists on your plate or perhaps it’s just a messenger inviting you to explore the relationship of mind over food?

In the end, fat is one of three very important macro-nutrients (protein and carbohydrate) that we all need to create a well-balanced, functional, energized human being. Exclude any one them for too long and you may run into trouble. The key, as always, is listening: to your heart, your gut, your hunger and your body. It’s not about dogma or finding a home for your dietary ego, it’s about be open to evolving nutritionally.

Besides, who says any one way of eating is meant to last forever? So are you still interested in a high-fat diet or a keto diet?

Here at The Institute for the Psychology of Eating we do NOT endorse or promote any particular diet or nutritional lifestyle. We do highly encourage that each person openly explores the wide variety of nutritional approaches and dietary strategies that are available to them. We see nutrition as an ever-changing journey. We believe that a healthy relationship with food and a well functioning metabolism is possible when we can each be open to what works best for ourselves, and others. We believe there’s a nugget of wisdom to be found in just about any diet that’s been designed with care in mind for people and planet.

A plate with high fat foods like avocado and bacon

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