Eat Fat to Lose Fat: Keto and Weight Management

Feb 15, 2024

One of the best benefits of ketogenic diets is the dramatic loss of unwanted body fat mass. The intention of this blog is to provide a simple description of what’s going on under the surface.

NEVER Step on a Scale Again

Before we get deep into this one, I have to give you the “Never step on a scale again” talk. When I work with family, friends or clients I always recommend using a body composition scale or machine to track progress, from the start. My favorite is the InBody machine but other brands like Garmin make these, too. You can find a gym, supplement store or PT practice that has one for public use. They also make an at home version with fewer data points. 

InBody test results show you data points that you simply can’t get without a more complex machine. Knowing more about what’s going on under the surface can help you (and your coach) make more informed decisions regarding your nutrition strategy. 

Data points I focus on with my clients from their InBody results include total body weight, body fat mass in pounds, skeletal muscle mass in pounds, percentage of body fat, visceral fat level and basal metabolic rate (BMR). 

Visceral fat is the body fat mass that is specifically carried on the torso and around the midsection. Visceral fat level can be an indicator of overall metabolic health. 

BMR is the least number of calories that must be ingested to sustain everyday bodily functions like the heart beating, the lungs breathing, the kidneys filtering, etc. If you laid in bed all day long and didn’t do anything the BMR is still the lowest number of calories you would want to consume to keep yourself alive. BMR is a critical number to know if you’re dabbling with the CICO method weight loss. 

InBody Locator Link

At Home InBody H2ON - pictured

Why NOT Calories In/Calories Out?

Caloric intake and energy expenditure are two major aspects of body recomposition, or decreasing body fat mass, however they are not the only two variables in the equation. We have to acknowledge the fact that the body and its processes, including metabolism, are largely governed by hormones. 

Calories in/calories out, or CICO, is a method of weight loss that most people try at some point in their nutrition and weight loss journey. The CICO theory focuses on the Law of Thermodynamics and states that if you eat less and move more you will experience weight loss, ideally a decrease in body fat mass. However, we know that for some, the weight lost is not just body fat mass, sometimes it’s skeletal muscle mass, which is less than ideal. 

The CICO method demands that you consistently consume less than your body needs which becomes a problem when we consider BMR and getting essential nutrients in adequate amounts. 

Here’s an example to better understand the body’s nutritional needs:

Let’s take a 30 year old, 5 foot 5 inch female. She is overweight looking to decrease her body fat mass, while maintaining her skeletal muscle mass. She works out 3-4 days a week at a local CrossFit gym. 

Her InBody results are as follows:

  • Total body weight - 203

  • Body fat mass in pounds - 98 

  • Skeletal muscle mass in pounds - 59

  • Percentage of body fat - 48%

  • Visceral fat level - Level 19 (Healthy zone levels 1-9)

  • Basal metabolic rate (BMR) - 1402 calories

If I were coaching this woman I would want to ensure that her daily intake is never less than 1402 calories, or her BMR.

If she consistently consumes 1400 calories or less, while she may lose weight, she’ll likely be missing out on essential micronutrients like vitamins and minerals. There’s no guarantee that the weight lost will be only body fat mass, and there’s also no guarantee that she will keep any lost weight off for the long term. 

Overtime, the lack of appropriate nutrient intake will reflect poorly on her overall health and wellbeing. In a constant caloric deficit she risks the health of her muscle and bone, brain and much more. 

Most individuals find that CICO is unsustainable and does not get them the life-long results they truly want. 

Hormones RULE the World

I used to say this to my clients all the time, “hormones rule the world.” I didn’t know exactly how true that statement really was until I took the deep dive into low-carb! 

The macronutrient composition of a diet is one of the strongest indicators of the potential for weight loss. Hormones and the effects that different foods have on hormonal responses are variables that the CICO model does not account for. 

Carbohydrate intake promotes an insulin response, while the consumption of dietary fat and protein does not. The body uses the hormone insulin to store energy. As long as there is consistent carbohydrate intake the body remains in “storage mode.” In storage mode the body cannot tap into the energy that it is carrying, it can’t break down or burn any body fat mass.

Breakdown Mode

If carbohydrates put the body in storage mode, then we need to figure out how to get into “breakdown mode.”

Ketogenic diets, including the carnivore diet, mimic a fasted state, hormonally speaking, and put the body into breakdown mode. This happens because insulin stays low and another hormone, glucagon, begins to increase and promotes lipolysis - fat breakdown. 

Once we greatly reduce regular consumption of carbs or completely remove them from our intake the body can begin to break down its own body fat mass for energy. 

Keto, carnivore and low-carb nutrition strategies have the potential to burn more than twice the amount of unwanted body fat mass compared with CICO, or low fat strategies. I’ve heard of (and worked with) individuals on keto and carnivore diets who lose up to 10 pounds per month, and keep it off without being in a caloric deficit at all.

For tips on how to make low-carb and keto strategies lifelong, review the keto-carnivore continuum from my previous blog The Carnivore Challenge: Navigating Uncharted Territory

Calories and the Hormonal Model

Now you have a baseline understanding of the role that hormones play in weight loss, specifically insulin and glucagon. So how do the hormonal and CICO models overlap?

Quite simply, caloric intake matters. If anyone on any nutrition strategy consistently overeats they will put on unwanted body fat mass. 

I can attest to the fact that on keto, and especially carnivore, nutrition strategies you don’t have to be as obsessed with your caloric or macro intake. In fact the “rules” on carnivore are:

  • Eat when you are hungry.

  • Eat until you are satisfied, or comfortably stuffed.

There is no weighing, measuring or counting calories or macros as long as 80-90% or more of your intake is coming from animal products, ideally fatty cuts of red meat. 

Eat Fat to Lose Fat

Protein, carbohydrate and fat are the three macronutrients that we get from the foods we eat. Protein is considered structural and is not usually used for energy, except in certain conditions. Carbs and fat are used for fuel, or energy. In keto, or carnivore nutrition strategies we reduce or remove carbohydrate intake which means we have to replace that fuel with dietary fat.

Dietary fat does not put the body into storage mode, rather it allows the body to remain in breakdown mode. Fat keeps you satiated, or satisfied, and can help prevent snacking and excess calorie consumption. Animal fats are nutrient dense and contain many essential micronutrients (vitamins and minerals) that are available for absorption and use in the body. 

Additionally, dietary fats are also used structurally in the body. Every cell in the human body uses fat in the cell wall, that’s multiple trillions of cells. This is further evidence against the CICO model. CICO only accounts for energy in and energy out, and does not account for the structural uses of nutrients like proteins and fats. 

A classic keto macro ratio is 70% of the intake coming from fats and 30% from protein, keeping carb intake at 10% or less. So… eat fat to lose fat. Focus on animal fats like tallow, lard, and other rendered animal fats (chicken, duck, etc), eat egg yolks, grass-fed butter, eat the skin, gristle, tendons and ligaments. Fat is flavor! Add these fats to your protein intake, and cook your low-glycemic load veggies in these fats. 

New “Rules”

If you follow these rules, or guidelines, you’ll likely have success in your weight loss journey:

  1. Prioritize protein - remember that protein intake increases with age so your macro ratios may change over time. Ex/ 60% fat, 40% protein

  2. Control carbs - low-carb means something different to everyone. I recommend downloading Cronometer, log your food intake for 2 weeks and observe your regular carb intake. Begin to slowly reduce intake over time. Low-carb for some may be upwards of 100 grams per day, to start. This won’t necessarily kick you into ketosis however you may experience some loss of body fat mass. 

  3. Fill with fat - get the rest of your calories from healthy fats. Let the majority of the fats you consume be from animal sources. Limit olive, avocado and coconut oils. Remove all seed oils and trans fats, including partially and fully hydrogenated oils. 

As always, my blog is not formal nutrition coaching. Any changes you choose to make to your nutrition strategy should be with the support of your medical team and maybe a nutrition coach.