How Many Calories Do You Have To Burn To Lose Weight? - AskMen
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      How Many Calories Do You Have To Burn To Lose Weight?

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      How Many Calories Do You Have To Burn To Lose Weight?

      Sorry, But The No. 1 Rule Of Weight Loss Is Wrong

      Why Is This Important?

      Because weight loss really is harder than you think.

      Long Story Short

      A new weight loss planner developed by the National Institutes of Health and a mathematician shoots down perhaps the single biggest myth in weight loss: Losing a pound of fat isn’t as simple as creating a 3,500 calorie deficit.

      Long Story

      Losing weight may be tough, but at least we know how it’s supposed to happen, right? Figure out how many calories you need to consume to maintain your current weight, and then subtract: For every pound of fat you want to lose, figure out how to create a deficit of 3,500 calories. To do that over the course of a week, you’d need a 500 calorie deficit each day. Hard to do in practice, but at least the math is simple enough.

      Except, it’s wrong.

      According to a new weight loss planner developed by the National Institutes of Health and mathematician Kevin Hall, the real number is something like double that amount.

      “The biggest flaw with the 500-calorie-rule is that it assumes weight loss will continue in a linear fashion over time,” says Hall. “That’s not the way the body responds. The body is a very dynamic system, and a change in one part of the system always produces changes in other parts.”

      There are several factors contributing to the “3,500 calories = one pound of fat” misconception. For starters, it’s not technically wrong — 3,500 kcalories is, in fact, the amount of energy given off by one pound of human fat when set on fire. The problem, though, is that our bodies are not furnaces, and using calories as a way to measure how fat a food will make us is crude at best.

      Sure, a 500 calorie slice of pizza has more energy in it than a 100 calorie serving of broccoli, but that’s about as far as it can take us. How our body breaks down and responds to different chemical compounds, macronutrients and hormones is actually more complicated than that.

      More importantly, the 3,500 calorie rule falls victim to something called “metabolic adaptation,” which means that as you change your caloric intake, your body adapts to function more efficiently. Cutting 500 calories per day might lead to a pound of fat loss in the first week, but each day your body becomes more adept at maintaining equilibrium on your restricted diet. Add in an exercise regimen (as do most people trying to lose weight), and the effect is compounded: As James Fell explains, a lighter, fitter body actually burns fewer calories, akin to a car using less fuel after a tuneup. 

      In reality, Hall says, actual weight loss over the course of 12 months is about half of what would be expected following the 3,500 calorie rule. Put another way, you actually have to create a deficit of 7,000 calories for each pound of fat shed.

      To be clear, that should not be taken as a sign that you need to cut 1,000 calories per day to achieve a weight loss goal of one pound per week — you’d be lucky if you could even last a week before caving and eating an entire pizza, at that rate. Instead, Hall says that dieters using the new weight loss planner should temper their expectations if they hope to lose weight safely and sustainably.

      “I suppose some people will be bummed out,” Hall says. “But we believe it’s better to have an accurate assessment of what you might lose. That way you don’t feel like a failure if you don’t reach your goal.”

      Own The Conversation

      Ask The Big Question: If this is true, does that make any substantial weight loss goal mathematically impossible?

      Disrupt Your Feed: On the bright side, I no longer feel like a failure for not losing weight.

      Drop This Fact: The “3,500 Calorie = one pound of fat” rule was first posited in 1958.

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