Home Debunking The Myths The Mathematical Myths of Weight Loss

The Mathematical Myths of Weight Loss

by Erika Nicole Kendall
The Mathematical Myths of Weight Loss

Hi. I’m here to gloat and discuss.

Mostly gloat, though.

The Washington Post published an article about “the mathematics of weight loss,” and I yell laughed – I mean, I YELL LAUGHED – my way through it. Not because it was funny – it wasn’t; the article actually ends on a “so why don’t you just give up and hit up the donut shop?” kind of note – but because it came to a conclusion that I’ve been saying for years here on BGG2WL.

No, really. Check this out:

There’s a popular rule you’ve probably heard before about losing weight: for every 3,500 calories you shed from your diet, you’ll lose a pound. But just because everyone, including nutritionists with graduate degrees, keep repeating this doesn’t make it true.

In fact, it’s a total myth.

“I see dietitians using it all the time, making recommendations based off of it,” said Kevin Hall, who is a researcher at the National Institute of Diabetes and Digestive and Kidney Diseases. “Unfortunately it’s completely wrong.”

For the record, I’ve seen numbers that quote everything from 1500 to 3500 calories being the primary marker for what determines a successful pound lost. In fact when Robert Lustig’s book, Fat Chance, mentioned that it only took 2,500 instead of 3,500, I immediately took that as a sign that we might know as much as we think we do about the hard numbers of weight loss. I mean, I certainly don’t know as much as he, but I pay enough attention to pick up on these things.

The issue that complicates this is that it’s rare that a person will go through the process of burning 3500 calories more than the total amount of calories they’ve consumed, and only lose one pound of body fat. There’s more to be lost in this situation that just body fat, and that plays a role in what you measure on the scale – when you sweat, for example, you’re sweating out water that once contributed to your weight. When you burn a bajillion calories in one sitting, you’re also burning muscle tissue as well, not just fat. It might not be a lot in one go, but it still affects your body fat percentage.

People get so caught up in seeing the scale go down, that they rarely pay attention to the kind of mass they’re losing. If you go into weight loss saying that you want to lose your “muffin top,” fine, but losing muscle only makes that more difficult, thereby complicating your ability to achieve your goals.

But…I digress.

The adage dates back to the 1950s, when medical researcher Max Wishnofsky measured how much energy a pound of fat tissue represents, and found that it was 3,500 kilocalories, otherwise known as calories. Theoretically, he had calculated how many calories a person had to burn—or forego—in order to lose a pound of fat. But Wishnofsky made a couple spurious assumptions.

First, he assumed that when you lose weight you only lose fat tissue. “That isn’t true,” said Hall. “It’s a relatively minor error, because a lot of it is fat tissue, but it still isn’t true.”

Not only did I just say that here, but I’ve been saying this for years. Your actual weight is a combination of body fat, lean muscle mass, skeletal mass, everything you ate and drank that since you’ve last expelled it all, biological mass (tumors, etc), and so on. Losing “weight” means losing any one of those by themselves or in tandem with the others. The problem with this is that, emotionally, people are attached to seeing a number on the scale; they also think that number will bring them a certain appearance, and are often disappointed when they don’t look the way they thought they would when they finally shrink.

The much bigger mistake Wishnofsky made was misunderstanding how our bodies react to weight loss. As soon as we start cutting calories from our diet, the number of calories our body expends begins to fall. “It literally starts happening on the first day,” said Hall. “And it continues to mount as you lose weight.”

Back in 2010, I said the following:

A 20lb weight loss alters how many calories our bodies burn in a given day by over100 calories! A woman who is 5’8″, weighing in at now 148 pounds, doesn’t burn 2,173 calories each day – she burns 2,025! If she’s counting to make sure she eats 1,600 calories each day,that’s only a 425 calorie deficit! That’s not enough to burn a pound every 7 days, it’s enough to burn a pound every 9 days. Meaning there may only be two Saturdays in the month where she sees any progress on the scale, depending upon where those nine-day markers fall.

After each successful stride in your journey, you must reassess your metabolic rate, be it for an athlete or a couch potato. You have to know what your body is doing, and you have to remember that as your size changes, your capabilities change.

Excerpted from The Math Behind Weight Loss Plateaus | A Black Girl’s Guide To Weight Loss

But I can expound upon that a bit more, now – not only is the amount of calories you burn at rest going to be lessened by a 20lb weight loss, but the amount of calories you burn when you’re active will also be decreased, too! You have to continuously reduce your calories and modify your workouts to make them more challenging, which plays a large role in your ability to maintain your weight, sure, but it’s also about you learning the best way to live your life at your smaller size.

For you, coming into a new size with your former past experiences and habits, you will likely need to work out in order to maintain. You can’t simply lose the weight and then go back to your old caloric intake, your own sedentary habits, your old anything. The point of adopting healthier eating habits and a more active lifestyle and using that to lose the pounds is because it helps you understand what life will be like for you at that size – and you can either take it or, happily, leave it. That’s why it’s so important to fuse your active lifestyle with activities that you enjoy. Zumba, Hip hop Dance, and so on. (I talk about this a lot in the training plan I just released, by the way.)

Moving on, though.

“Over time, the more weight you lose, the more your metabolic rate drops,” explained John Peters, a leading researcher at the Anschutz Health and Wellness Center at the University of Colorado. “In order to keep losing weight at the rate you started losing weight, you’re going to have to eat even fewer calories. A month in, you might have to eat another hundred fewer; a month after that you might have to drop it another hundred.”

Sort of. The more weight you lose, the more your metabolic rate drops, sure… but you never lose the ability to rebuild your metabolism through an increase in muscle. Never. Some people might even be better suited by focusing on the muscle building first and then using the muscle to help them lose weight since their metabolism would be so high in the end (people like me.)

It shouldn’t be framed as “the more weight you lose, the fewer calories you have to eat.” It should be understood as “as my body changes, so will my metabolism.” A loss of fat and/or muscle means your metabolism may take a huge hit. But an increase in fat and/or muscle means your metabolism can increase. If you want your metabolism to increase in a healthy way that allows you to eat a little more realistically for your lifestyle, you’ll build the muscle. Period.

The disappointing reality dieters face is that our bodies work tirelessly to defend our weight, even when that weight isn’t ideal. The metabolic changes are actually only one of three biological adjustments that follow severe cuts in calories—there are neurological and hormonal changes that happen too, both of which make losing weight and keeping it off a significant challenge. In fact, it can be nearly impossible. For these reasons some researchers say diets don’t actually work.

For the record, diets don’t work. Mainly because the hyper-simplified idea of “do this, not this, fixate on this, and boom! pounds!” doesn’t cover enough of the factors that largely contribute to weight gain and unintentional weight maintenance. Diet plans don’t talk about muscle – it’s still seen as manly and, let’s face it, the majority of diet culture is targeted at women – and they don’t talk about actually enjoying the food you eat, which is a large part of what makes people so damned miserable.

Neurological and hormonal changes are often related to what people cut from their diets – not just how much they cut. It would make sense that a shrinking figure would require a shrinking amount of stuff, not merely just “less stuff.” You still need vitamins, minerals, antioxidants, electrolytes, protein, fat, carbs – yes, carbs – and so on, but if you’re cutting mass quantities of stuff, are you sure you’re getting everything?

“Nearly impossible?” Of course. It’d also be nearly impossible to drive completely across the country without a map. Folks need better maps when it comes to weight loss, starting with the fact that people need to accept that it’s not merely “cutting calories” – they need to understand that a calorie is not just a calorie. Period.

You cannot build muscle on carbs, and if carbs are close to two-thirds of your diet, you’re not getting enough protein to build that muscle. You’re not getting enough protein or fat to stay full without feeling hunger, feeling the compulsion to overeat, or keep yourself properly nourished. All calories are not equal, no matter how many industry experts tell you otherwise.

I’m glad this was written, even though the tone of the essay was so “So, let’s just give up and go get cupcakes, yeah?” The important takeaway from this, for me, is the fact that you have to understand that this is about adopting a new life that will allow for you to train the way you should and eat the way you need to in order to maintain what you’re after…and the converse is also important – you have to train the way you should and eat the way you need to in order to make that new life (and figure, for that matter) permanent. The “all diet, all cardio” mentality, as a whole, is lose-lose.

What did you think?

You may also like