Fat loss excpectations. How much and how fast weight can you lose?

Research done by CDC concluded in 2013, that 70.7% of adults age 20 and over are overweight (this includes obese) 

7 out of 10 people in US are overweight. 

Between 1988 and 2014 the amount of people in US with a BMI equal or higher than 25 has increased from 56.0 to 69.5

A staggering 13.5% increase which is over 40 million people translated in population numbers.

40 million in 24 years or in other words 1,66 million a year.

This is all of course frightening and horrible but It's 2017 now and people are more than ever interested into getting in shape. No big surprise there, It's in our nature to fuck up first and start obsessing over fixing it afterwards.

That's the just part of humans psychology and I've seen it a million times when it comes to getting in shape. Same reason we do so bad with money, we max out our credit card and think of how to pay it off only after when It's already too late to implement a cookie cutter solution.

In truth, losing weight is almost always easier than it is to get out of debt. For some It may not seem that way but that's mostly because they've been inducted into 'average' thinking when It comes to their bodies.

If you do what the 70% of your countries population do, then you will look like the 70%.

Think about it. Do you exhibit the same habits and daily rituals that the majority of people do? Why would you end up in a different scenario If you do?

Statistics and facts are cold and harsh. People don't like cold and harsh, that's how many of us get sold by seemingly ridiculous marketing tactics. People promising us phenomenal results in a hilarious amount of time.

So you want to hear some cold harsh truth? Maybe just need to get off your fat ass and start living the life you were meant to live.

Let's analyse a a typical goal I've heard on the web

Can you lose 15 pounds in 30 days ? 

Let's work some numbers out. 

Let's look at a hypothetical person. George is an average skinny-fat male with a belly.

So I used calculator.net to get an initial BMR.

Ignore the recommendations for caloric intake they provide there as I didn't even check their accuracy, we will do the math ourselves.

Also, I purposefully included a sedentary activity level as we will speculate on the cardio ourselves.

So George needs 2,166 kcal to maintain his weight at the beginning of his weight loss journey.

He supposedly lost 15 pounds in 30 days (a typical claim by fat loss ads) 

So how much of a caloric deficit do you need to lose 1 pound of fat? 

The answer is not very satisfying.- It varies.

Ir varies on the lipid concentration of the fat but we have some numbers we can base our math on. 

Between 72 % and  87%  of body fat tissue is actual fat so 1 pound of fat contains between 317,8 and 394,98 grams of fat, There is also some research that suggests a variety in calories per gram of fat, the numbers I found varied between 8,7 - 9,5... 

So the amount of calories you need to lose 1 pound of fat will vary between 2,843 and 3,752 

Let's agree to go with the middle ground here, which would be 3207.5

Assuming this number we would end up with a 48,112,5 caloric deficit over the span of 30 days to achieve the insane goal. 

That's a 1603,75 caloric deficit per day! 

And It gets worse. With each kilogramme of fat you lose, your metabolic rate adjusts and becomes slower. That's why extremely fat people can lose weight extremely quickly.

The metabolic rate for our hypothetical George wouldn't drop too fast within losing the 15 pounds but 

by the end of his fat loss his BMR would be at 2,082, which is 84 calories less per day! 

So you think that's insignificant? Well, It's  almost 4% of lost BMR. I want you to realise that once you lose weight, It's harder to keep it off, often just because you now need to eat less than you did just to maintain. Which is one of the main reasons why I believe in gaining muscle for beginners before you begin cutting.

Ignoring the BMR loss caused by the weight loss, we can still do the math.

George needs a 1603,75 calorie deficit per day, meanings there's just  562.5 calories left for him to consume... That doesn't work. You can't even get all your macro nutrients, not even mentioning micro nutrients and just the impracticality of such a diet.

Beyond any doubt. We need to add cardio.

So to keep It simple, let's assume George did 4 sessions of 60 minutes of running on a treadmill at the speed of 10 km/h in a week.

That's a lot of cardio. So 4x60 = 240 minutes/ weekly.

So based on Runnerworld.com calculator each session would burn a total of 829 kcal.

For a weekly grand total of 3316 deficit from cardio alone.

Well, that's all fine and dandy but what about the after-burn effect? 

So what is the after-burn effect in the first place?

The after-burn effect or in the more precise and less 'market-friendly' is called excess post-exercise oxygen consumption. (EPOC)

We can conclude from these studies, that first of all It's just incredibly hard to be accurate about how much calories exactly will be 'after burnt' and at the extreme most It'll be no more than about 200 kcal.

Yes, It's a myth that you burn as much calories during EPOC as you did during the workout. And all the bullshit about HIIT having magical benefits to your post-workout EPOC. It's a marketing sham.

Summary.

2166 kcal BMR
3207.5 kcal deficit = 1 lb fat loss
1603,75 Average Caloric deficit required to achieve goal 
4x60 minute session of cardio that come at 829 kcal 
4x60 minute session 'hypotetical' afterburn - 200 kcal each session.

Monthly caloric balance.

BMR - 64,980 kcal
Deficit required - 48,112.5

Cardio - 4x829 = 3,316 + 800 (EPOC) = 4,116 kcal / week = 16,464
Deficit from nutrition - 500 x 30 = 15,000

Total deficit - 15,000 + 16,464 = 31,464 (9,8 pounds of fat)

Conclusion.

You can lose a lot of weight quickly. However as you can see It's not that easy, to lose just these 10 pounds, which is well below what most peoples goals are anyway, George needed to alter his life A LOT. 

In fact I'd say the given routine is completely unsustainable and I would not advice it as it could have negative effects on your health.

Let me explain the seriousness of the given routine.

60 minutes of running a day at 10 km/h. That's a pretty serious work out if you do that 4x a week.

And most people wont do that. A typical regime for someone losing weight nowadays is someone who will do maybe 120 minutes of cardio a week and some weight lifting.

If you're thinking weight lifting has huge benefits to losing weight, then you're in for a surprise.

While I agree completely that long term weight lifting will make weight loss far, far easier, It's clear that in the short term It has little benefit to actual weight loss, except for muscle preservation which is backed by studies but is not the main concern for beginners in the fitness world.

Just check out these numbers, weightlifting plays little role in creating a caloric deficit, there are certain ways you can maximise it and i might cover it in a different article but for now It's a minimal part of the weight loss equation.


On a little more positive note, It is possible that our hypothetical person, George did lose 15 pounds of weight after all. Here's the magical thing about weight loss - You can lose not just fat but other tissues as well. Muscle will be lost. 

This study tells us that losing weight slower will benefit you in the long run because you will lose less muscle. You really don't want to lose all that fat just to look like a skinny cow.

And beyond muscle wasting, there's also glycogen depletion, intramuscular water depletion, dermal water depletion, believe it or not just changing your nutrition and activity level will change the content of your gut.

I know It's nasty but inactive people that eat an unbalanced diet are full of shit. Literally.

All these factors combined it's possible that a 9,8 lb fat loss could translate into a 15 pound weight loss. In fact, I would speculate that even as small as a 2-5 lb fat loss can translate into a 15lb weight loss in some cases.

You would not believe how often people I've had as clients would come to me and tell me insane things like 'my friend lost 20 pounds in a month!' or 'someone I know lost 3 pounds after just one workout!'

If you've actually read this far you know exactly why that's complete bullshit and incredible cringe to listen to. 

The most important thing to conclude is that weight loss and fat loss are two completely different beasts.

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FitasBoss - 

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References.

https://www.ncbi.nlm.nih.gov/pubmed/17101527

https://www.ncbi.nlm.nih.gov/pubmed/9049750

http://www.health.harvard.edu/newsweek/Calories-burned-in-30-minutes-of-leisure-and-routine-activities.htm

http://www.webmd.com/diet/news/20140529/fast-weight-loss-may-mean-muscle-loss