Nutrition Mythbusting: Does Paleo Reset and/or Boost Your Metabolism?

Article written by Joe Nissim

Glory Days

RU Logo

R-U Rah Rah!

R-U Rah Rah!

Hoo-Rah! Hoo-Rah!

Rutgers, Rah!

Upstream, Red Team!

Red Team; upstream!

(Men) Rah! (Women) Woo! (Men) Rah! (Women) Woo! (All) Rutgers, Rah!

I can’t tell you the amount of times I was slobbering down wings and chasing them with a beer, while screaming the Rutgers fight chant during my college years on the banks of the ole’ Raritan at Rutgers University.

In those days, I was a competitive weightlifter.  My diet consisted of something like ⅓  dining hall food, ⅓ pizza, and ⅓ booze.  Somehow, no matter how many slices I downed at 2AM, I never put on any pounds.  It was awesome.

Then I graduated and started my career in finance.  My weightlifting career crashed and burned after 3 wrist surgeries in my first postgraduate year. So that meant I was spending 8-12 hours per day at a desk.  A combination of sitting on my ass and binge drinking almost every weekend led to me starting to pack on the pounds by age 28.  50 pounds to be exact.

My immediate reaction was to blame my Mom and her side of the family for the turtle speed metabolism.  (Of course, not my lifestyle or my spare tire.)

Then I started seeing stuff online that claimed that the Paleo diet could reset and boost your metabolism.  Hmmm… I was intrigued.

The basic logic was by eating foods that were only available during the paleolithic era (aka caveman times) that the body’s metabolism would adjust in a very positive way and begin burning fat in no time.

So I decided to explore this to see if it was true.

First things First: What is Metabolism?


Metabolism is a word thrown around the internet way too recklessly by the nutrition industry.  If you read the thousands of articles online, it will make you believe everyone has a slow metabolism, but some super juice will make it faster.

So let’s start by understanding what metabolism actually is:  Metabolism is the amount of calories your body burns in order to stay alive.  This includes both the amount of energy our organs and brain needs, as well as the amount of calories needed to PR your squat.  Metabolism is broken into two distinct processes: Catabolism and Anabolism.

Catabolism is breaking down food into nutrients that our body can actually use.  For example, when we eat chicken, our body breaks it down into its building blocks, known as amino acids.  Those amino acids can be used as energy.

Anabolism, on the other hand, is where our body takes those nutrients, protein, carbohydrates, and fat, and uses them to rebuild our body.   Remember that piece of chicken? Those amino acids that it breaks down into can also be used to help rebuild our muscles after a long run or lifting sesh.

These two things together make up metabolism.

How does my body burn calories?

1000 calories

This is a shame. What did the pizza do to you?

There are three main ways that our bodies burn calories.

#1 – RMR – Resting Metabolic Rate

RMR is the amount of energy you need to keep your blood pumping, your brain functioning, and muscle moving.  RMR is the biggest component of your daily calorie requirements. 60-75% to be exact.

Side note: RMR is commonly referred to as BMR (Basal Metabolic Rate).  Even though they refer to essentially the same thing, BMR is primarily used in labs and is really strict.  For our purposes, RMR is easier to use and way more useful.

#2 – Activity (aka Activity induced thermogenesis)

This is the energy you need to do anything like get up, move around, be on your feet, and most obviously, exercise.  This is the most important to us because:

  1. It is the most variable

  2. It is the easiest to change

  3. It is the most controllable

Here’s the kicker. Unless you are an elite athlete or a psycho exerciser, this will never be where most of your calories are burned.  For most people, the amount of calories burned through activity will increase when:

  1. We start exercising

  2. We increase the amount of time we spend exercising

  3. We increase the intensity of exercise

But exercise is not the entire story when it comes to activity induced thermogenesis.  The amount of calories needed for activity is determined by what you do all day, not just by the one hour of exercise.

Therefore, if we take two people whose exercise regiments are exactly the same, but one of those people is a school teacher who is on their feet for 6-8 hours per day, and the other is someone who sits at a desk, the school teacher will require and burn more calories than the desk jockey.

In total, activity accounts for roughly 15-30% of calories burned per day.

#3 – Digesting Food (aka Diet induced thermogenesis)

This one is the simplest.  It is the energy you need to break down and absorb nutrients from the food you eat.

This accounts for roughly 10% of calories burned per day.

So far so good?

So let’s put it together

RMR, as we learned above, is what our organs, tissues, and muscles need to work.  Well, how is this amount determined?  I made a little chart:Heart/Lungs/Kidneys~ 440 cals per dayBrain~ 240 cals per dayFat Tissue4.5 cals per kilogram of fat body massMuscle Tissue15 calories per kilogram of lean muscle mass

When our body has more muscle, we tend to burn more calories naturally.  Each kilogram of muscle burns 3.3x more calories than a kilogram of fat.

So listen closely: that means the #1 determining factor of metabolism is…. body composition.  Remember RMR is 60-75% of calories needed.  The biggest part of RMR is the amount of muscle tissue on our body.  This then means that body composition, or the amount of lean muscle mass vs fat mass, is the #1 contributing factor of metabolism.

Now, this does not mean that RMR is the only contributing factor, nor does it mean that if you are a well-muscled dude or chick that your metabolism can’t be slow.  There are other contributing factors such as:

  1. Genetics

  2. Race

  3. Gender

  4. Eating too little

It is still unclear the amount that each of these contributes, but science has concluded that they do make a contribution.  The answer to metabolism is not cut and dr,y and there is still a ton of research that is going into it each year.

So let’s circle back to the original question: Does Paleo “reset” your metabolism?

Before saying “yes” or “no,” let’s understand the argument.

Paleo purists believe the following:EatDo Not Eat●     Grass-fed meats.

●     Fish/seafood.

●     Fresh fruits.

●     Fresh vegetables.

●     Eggs.

●     Nuts.

●     Seeds.

●     Healthy oils (olive, walnut, flaxseed, macadamia, avocado, coconut)

●     Cereal grains

●     Legumes (including peanuts)

●     Dairy

●     Refined sugar

●     Potatoes

●     Processed foods

●     Overly salty foods

●     Refined vegetable oils

●     Candy/junk/processed food

Further, they believe your plate should look something like this:

Photo credit: Wodnut Paleo,

Photo credit: Wodnut Paleo,

Photo credit: Wodnut Paleo,

The main argument is as follows: By eating foods free of hormones, genetic mutation, and rich in micronutrients, the body’s hormones will function properly and therefore regulate metabolism.