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Insulin: Body Weight and Energy Production Part 1

ByCrossFitMay 22, 2020

On March 12, 2010, Coach Greg Glassman and a small crew visited Dr. Scott Connelly in Los Angeles. The intent was to tap into Dr. Connelly’s vast knowledge of metabolism, particularly as it relates to long-term fitness and health.

The result was over 90 minutes of education about the relationships among glucose, insulin, ATP, protein, body weight, and health.

Topics include:

  • Why a calorie is not just a calorie.
  • How insulin resistance was evolutionarily beneficial.
  • How “dieting” can make you fatter.
  • What happens when you hit the calcium wall.

Originally published April 4, 2010.

Comments on Insulin: Body Weight and Energy Production Part 1


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Tyler Hass
May 23rd, 2020 at 11:12 pm
Commented on: Insulin: Body Weight and Energy Production Part 1

I rewatched this a few months ago and here it is back on the front page. It’s an incredible whirlwind of a presentation. Dr. Connelly really knows his stuff. He goes non-stop for an hour and a half on insulin and as best I can tell, he doesn’t even have notes to read from.

My favorite part is at roughly 8:00 of part 1 when he discusses the calorie balance hypothesis. He completely shatters it using basic reasoning from elementary chemistry/physics. Comparing mass on one side of the equation to energy on the other side simply doesn't work. It’s so obvious once he points it out. If you like this section as much as I did, Zoe Harcombe has done a whole speech on the topic: Kettles, Calories & Energy Balance: What went wrong? by Dr Zoe Harcombe PhD. The human body is nothing like a bomb calorimeter. If you want to understand anything about weight loss, you must understand insulin and the metabolic pathways that drive fat deposition.

Towards the end (30:00 of part 3), he discusses his protein intake, which would be controversial in many circles. Some longevity experts warn against high protein intake, as it stimulates the mTOR pathway. I'd love to see Dr. Connelly debate on this topic.

Some key takeaways:

Part 3 4:10 Get your vitamin D levels tested. Most people are devastingly low. Then figure out a dosing strategy to get them back up.

Part 2 4:30 Glycemia is the biggest threat to health today. The 55% carbohydrate diet is a disaster.

Part 2 24:00 Protein intake is discussed. The RDA recommendations are based on percent of calorie intake (15%). It should be based on bodyweight.

Part 3 8:20 Discusses the importance of triglyceride/HDLc ratio. It’s a cheap, easy blood test that correlates extremely well to insulin resistance and cardiovascular disease outcomes. It’s the best measurement of metabolic health.

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Georgios Gramatikakis
May 23rd, 2020 at 10:47 pm
Commented on: Insulin: Body Weight and Energy Production Part 1

I enjoyed the lecture. The information was relayed in very clear manner and I felt that much of what was said made more sense than the calorie theories that make up most of what is commonly taught regarding fat and insulin. There is however some negative press regarding Dr. Connelly’s educational background and his former supplement businesses. I am curious as to the community’s views on the accusations he has faced. Does anyone have more information or insight into the credibility of the information in the videos?

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