The New Math on Weight Loss: Goodbye 3,500-Calorie Rule

By: Scottsdale Weight Loss Center

Published: January 24, 2019

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For years doctors have been telling their patients to cut out 3500 calories and they will lose 1 pound of fat. By cutting 500 calories daily, one should lose a pound each week. The calculation came from simple thermodynamics: If one burns a pound of fat in a bomb calorimeter, it releases 3500 Kcals. So, it would stand to reason that our bodies are just a simple physics equation. When their patients did not lose weight, they surmised the patient was overeating. Studies have since proven the 3500 calorie per pound theory wrong, as challenged by the following article in NEJM.

The new math on weight loss: Goodbye 3500 Calorie rule

So, the new math shows that one must create a calorie deficit of between 4500 and 7000 calories for each pound of fat. The reasons behind this include:

Reduction of calories and weight loss leads to lower levels of the fat burning hormone leptin, resulting in a lower metabolism.
Reducing calories often leads to decreased levels of physical activity.
Creating a calorie deficit from increased activity often leads to compensatory increases in intake.

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Nick's Story

"I wish I would have come here first. We spend all our time reacting to the next great weight loss tip or program. It might work for a while, but does not last and we end up yo-yoing from one fad to the next – as we gain more weight." Read More

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Lost 44.5 lbs

"I had no trouble adhering to the meals and they really helped catapult my progress! The classes were so beneficial to me because they helped change my thinking about how I viewed health, nutrition, and fitness.

I will always have my relationship with Scottsdale Weight Loss Center. They truly helped me change my life forever." Read More

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Lost 60 lbs

"Dr. Ziltzer and everyone who I have come in contact with at the Scottsdale Weight Loss office have been so encouraging and I look forward to seeing them each week. It is now a year and 2 months later since I started. I am down 60 lbs., which is the average amount a 9-year-old weighs, it is crazy to think I lost a whole person! I feel amazing, I hit my goal weight in November 2021 just before Thanksgiving. Nothing on my body hurts anymore..." Read More

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Lost 66 lbs

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Lost 101 lbs

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   Trustindex verifies that the original source of the review is Google. I'd lost 20 pounds on my own and struggled to keep it off.  I decided GLP-1 meds were the next step in losing more and keeping it off.  I wanted a medical doctor supervised program and chose SWLC. I am so very glad I did!  The team in Glendale is so supportive and kind; and when I feel discouraged, they pick me up with positive energy and input.  They really do a great job with encouragement all the time. 6 weeks in I've lost 17 pounds, and am approaching weight loss with a very new perspective.  Also knowing that when I reach my target goal, they'll be there through maintenance and beyond is encouraging as well.  Good to not feel alone on this journey.
     
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