I took a look a while back at Metabolism and Aging. The chart in that article shows the Basal Metabolic Rate (BMR) which is an estimate of how many calories you’d burn if you were to do nothing but rest for 24 hours. BMR represents the minimum amount of energy needed to keep your body functioning, including breathing and keeping your heart beating.
Total Energy Expenditure
But you probably do more than that and there are various additional calorie burners such as any activity, etc. Even the digestion of food consumes calories with each of the macros burning a different percent of their calories to digest the calories. See the article – Thermic Effect of Food and Metabolism of Food.
All of these lead to something that I call the Metabolic Burn Rate. It’s a composite number made up of the ratio of your caloric intake (at maintenance) to your body weight.
My current body weight is 165 lbs and my caloric intake is around 2400 calories. That’s a ratio of 14.5 calories per lb.
How is it that Fat People Seem to Eat Less?
When I was 285 lbs people commented that they rarely saw me eat. And I ate very little food. I wish I had food logs to help make the point so I have to go from memory. Here was a pretty typical day for me:
Here’s the macros for my pre-Low Carb diet.
I may be underestimating carbs since my Insulin pump shows my daily carbs as higher (200 grams of carbs a day on the average) but I’m not too far off. It must be a fairly accurate representation of my caloric intake since my weight was stable (and I can estimate my caloric usage to work the number backwards).
Calories In/Calories Out?
Here’s my claim that is amazing and few people will believe. In spite of the fact that I have lost 120 lbs my number of calories expended per day is nearly the same. It’s all due to activity level.
But, let’s pretend like I am wrong about all of this and show the same thing from the Calories calculator. Looking at both weight/calories numbers side by side:
Nearly the same amount of calories but at quite a different weight. The difference is activity level.
- My metabolic burn rate used to be 2552/285 = 8.9 calories per lb.
- My current metabolic burn rate is 15.7 calories per lb.
My Advice to Fat People
- Don’t exercise if you are 285 lbs.
- It is dangerous.
- Exercise and weight loss don’t go together (Diet Plus Exercise Equals Diet).
- Do Low Carb.
- Lose a bunch of weight.
- Then add activity as you are fit to do so.
- In fact, it will add itself nearly automatically as you lose weight.