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Diet - The Theory Is So Simple

By: :Phoenix Fitness 0 comments
Diet - The Theory Is So Simple

There used to be a time when everything was so simple, we were told if you create a calorie deficit you would loose weight. However, this didn’t always work. There as been recent research that has debunked the ‘calories in’ vs ‘calories out’ theory, so where does that leave us? 

The problem is the CICO theory was based on the First Law of Thermodynamics unfortunately we are not machines and our bodies work in very different ways.

what is a calorie

What is a calorie?

To put it simply, a calorie is a measure of energy. A “large calorie” is a measure of food energy. A “small calorie” is the approximate amount of energy needed to raise the temperature of one gram of water by one degree Celsius at a pressure of one atmosphere (yawn, right?). Here’s more to confuse you, a large calorie is made up of 1000 small calories, so what does that matter you? Absolutely nothing but the food industry and nutritionist talk about amount of calories in food and we can use as a reference.

The Theory’s Simple

3500 calories equals one pound of body fat. If you cut 100 calories from someone’s diet they’d reduce their caloric intake by 182,500 calories over a five year period.

If we put a male at 5’8″ who weighed 165 pounds on that diet, they’d lose 52 pounds over 5 years. If they overate by the same amount they’d be obese?

Now the theory maybe simple but I have stories in my own life that show this doesn’t work; when I was a lot younger I had a very good friend and he was skinny but we used to go to the gym. One day Lee turned to me and said ‘I’m going to try and bulk up’ and he started drinking pints of full fat milk everyday on top of his normal diet, a month later he had lost weight. At the opposite extreme my wife who has started complaining that she has recently put weight on (however she’s had two children and is now the wrong side of 40) When I take in to account she eats sugar like it’s going out of fashion and thinks nothing of eating a family size bar of chocolate every night and has never put on any weight until recently, there’s something this theory just isn’t covering.


The body is a wonderful thing, I had an urge to write machine there but it’s not a machine, all machines work and perform the same, our bodies are living organisms and as such affected by things around us and things we put into our body. The body as also evolved over many 1000’s of years but it still hangs on it’s past and this can effect how it reacts to calories you put into your body.

You can live quite happily on whatever diet you eat and then one day come to the conclusion that you need to loose some weight so restrict your calorie intake. What happens? You lose weight but very quickly the body says to itself emm I’m wasting away here as I’m not getting enough energy so begins cutting down on non-essential energy use, you start to feel sluggish and your body learns to live on less calories, you stop losing weight, lose confidence in the diet and start eating again, body thinks time of plenty and stores some energy as fat in case of famine again.

Basel Metabolic Rate


Basel Metabolic Rate

So if cutting calories doesn’t work what next? Calculate the number of calories your body actually burns each day to perform its basic, life-sustaining functions. This includes all the involuntary processes in your body such as breathing, digesting food, pumping blood, brain activity, and much more. 

There are many very accurate and technical methods to determine your BMR but it can be roughly calculated using the following Harris-Benedict equation to calculate your BMR by hand and to the layperson is close enough.

Women: BMR = 655 + (4.35 x weight in pounds) + (4.7 x height in inches) – (4.7 x age in years)

Men: BMR = 66 + (6.23 x weight in pounds) + (12.7 x height in inches) – (6.8 x age in years)

Remember this is the amount of calories you need to survive if you don’t move out of bed all day so you do need to take into account daily activity and physical exercise if taken.

Thermic effect of certain macronutrients

Now earlier we said that not all calories are the same and here’s another reason why, the thermic effect of food is the caloric cost of digesting and processing different macronutrients in your diet. 

  • Protein: 20-35% of calories burned through processing
  • Carbohydrates: 5-15% of calories burned through processing
  • Fats: 0-5% of calories burned through processing

To put this in real terms, if you eat 200 calories worth of protein, your body will use between 40 and 70 of them in digestion.

What should we eat?

So now we understand what a calorie is, how to work out how many calories we need to survive, why we shouldn’t starve ourselves and that measuring calorie intake may not be that accurate, but what should we eat?

In the 1960s, experts started advising people to eat less fat—based on the belief that a high-fat diet led to a high-fat body—obesity has skyrocketed.

“Despite eating less fat, we are fatter than ever before,” said David Ludwig, professor of nutrition at Harvard T.H. Chan School of Public Health, in the January 2016 issue of Boston magazine. So that didn’t work but many still believe this myth and to be honest it’s only recently I stopped eating low fat.

The truth is nobody really knows, there is far too much self-interest from both the food industry, so called diet experts or people making money from fear. The only thing I can say for sure is whatever you choose to eat don’t starve yourself, be realistic, eating sugary cakes and puddings aren’t going to make you lose weight however the odd one may be good for the spirit and your mental health. Eat nutritious whole foods that are not overly processed and if it contains anything you cant spell don’t eat it, the other caveat is go for high density nutritious foods that give up their nutrients easily.

From there you should have a healthy, nutritious diet and not be starving all the time, from there you can start removing foods or food groups ie carbs, or fat and see how they effect you, but remember the best measure of a health weight is how you feel, perform and look in the mirror not how much you weigh.

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categories : Lifestyle