How to Critically Consider Metabolism Myths – Part 2


Yesterday, we presented the myth that muscle burns more calories than fat. As discussed, this holds true overall all but even adding as much as ten pounds of muscle will only allow for eating about 60 extra calories day. Lose some fat in the process and you’ve negated those extra calories even further.

Clearly, having more muscle does not “rev up” the metabolism and turn anyone into a “fat burning machine”.

Today, we continue on with our 10-day study of metabolism in regards to losing weight and look at the second myth of metabolism.

Myth #2 – Eating More Protein Increases TEF, Increasing Metabolism

Man eating food in kitchenTEF is the Thermic Effect of Food and is also known as Dietary Induced Thermogenesis (DIT). It is true that your body must utilize more energy when processing the protein you eat as opposed to any other macro-nutrients (the three macros being protein, carbohydrates and fat).

What me must question is rather TEF allows one to eat a significantly greater amount of food or is the difference only marginal?

Here is how to calculate TEF:

  • Protein – 20 – 30% of the protein you eat is used in the energy process to absorb it.
  • Carbohydrate – 3 – 15% of the carbs consumed are immediately used for energy (sugary carbs require less energy to break down).
  • Fat – 0 – 5% of fats are used for energy absorption as fats are already in the form of readily available energy

TEF might allow you to eat a few more calories if you are getting a lot of protein in your diet but the amount is insignificant.

Let’s consider a guy trying to build muscle and deciding he needs 1 gram of protein per pound of body weight. At 200 lbs, that’s 200 grams of protein (800 calories). If his total daily intake is 2,500 calories, that’s 32% of his daily intake coming from protein.

This same guy decides he’s going to increase protein to whopping 50% of his total calories, because TEF will allow him to eat more. He’s now eating 1,250 calories of protein a day – or 313 grams.

Well the first problem is fighting off that gas problem, but getting past that and assuming an unlikely maximum DIT of 30%, that’s 375 calories a day the body will use for energy, compared to his original TEF of 240 calories for an extra 135 calories a day.

But then, in order to maintain 2,500 calories a day, he needs to make the difference up by decreasing carbohydrates and fat. Fats are unlikely to be decreased because it’s in a lot of food and most guys understand the importance of getting quality fat in the diet.

The 450 calories less in carbohydrates (and we’ll assume maximum TEF again to make this easy), means the total TEF gained is now 15% instead of 30%.

The difference is less than 70 calories a day and that’s with a fairly high daily caloric intake of 2500 calories. Enjoy that extra Oreo cookie.

TEF is highly variable so it’s also worth nothing that there’s no way to know exactly how many calories are being burned through the process.

The above scenario would also leave a person without an ample supply of carbohydrates. All those hormones that positively affect muscle growth will suffer severe consequences. In short, you’re making it much harder to achieve your weight loss goals.

There’s also 2 more situations where TEF is decreased.

  1. Individuals with insulin resistance (pretty much anyone with excess body fat has this issue) will be on the low end of TEF. Insulin resistance is associated with a low TEF
  2. Individuals who engage in ongoing exercise and become more fit experience metabolic adaptation and a decreased TEF.  DIT becomes a nearly insignificant part of total daily expenditure (Katch, FI & McArdel WD, 1993).
What is Metabolic Adaptation?
Metabolic adaptation is the body’s ability to adapt and overcome a stimuli that previously produced a greater result, as the body continually seeks to maintain a state of homeostasis.

Clearly, the effects of TEF are overstated and trying to gain an extra advantage in eating more, in regards to DIT, is a frivolous pursuit. Want to eat more? Exercise more and burn more calories.

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