How many Calories are in a 1 pound of human fat ??

[302efi]

Anyone know ?

 

[Witling]

Well, right off the bat, what question are you really asking? Although you may really be asking something else, here are two choices: (1) If you burn a pound of human fat, how many calories are released? (2) How many dietary calories are needed to form a pound of human fat? As you may or may not know, the calories used in the nutrition field are really kilocalories. I trust I don't need to define a kilocalorie.

 

[damonpip]

Fats are usually considered to have 9 dietary calories per gram. 1 pound is 453.59 grams. So 1 pound of fat has about 4080 dietary calories.

 

[bobsmith1492]

I'll look it up... my physics book had a question to do with that

I don't know if dietary fat is the same as human fat as far as calories per gram....

EDIT: Ok, the question says "Assume this much fat burning [1lb] requires 3500 Cal to be transferred."

So it says 3500 Cal (that is, kilocalories) per pound of human fat. Pretty close to damonpip's calculation.

 

[302efi]

Thanks guys...I need to burn 120,000 kilocalories to get in shape:Q

 

[bobsmith1492]

Well, the problem in my physics book was: how many liters of ice water would you have to drink to burn one pound of fat (the energy would be going only into raising 32 degree water up to body temperature).

You could try it!

However, upon solving the problem, it turns out you would need to drink some 478,000 liters of water....

 

[imported_Macros]

one lb. of fat is 3500 calories.

Also, while exercise does help, it takes an enormous ammount of it to burn even 1 lb of fat (considering an average hour of intense running would burn only 600-800 calories). The best way to lose weight is to cut back on consumption to where it is about your BMR or basal metabolic rate(the energy your body burns at complete rest in order to stay alive) which is about 1800-2000 calories for an adult AND at the same time incorporate exercise and strength training into your daily workout.

 

[Dough1397]

calorie = 1J
Calorie = 1kJ

so i learned in a bio class that 1 gram of fat has 9kcal so i assume thats 9 Calories and times that by 453.5 and you get the approx amount

 

[ddviper]

so if u say on ur @ss the whole day didnt move, and ate more than 3500 calories, ud be one pound heavier?

 

[bobsmith1492]

1calorie != 1J

1 cal = 4.19J

1Cal = 1000 cal;

1Cal = 4190J



Trusty physics book they wouldn't buy back.....

 

[bobsmith1492]

Whoa dude... we posted at the same time!

Actually your body burns a lot of energy just breathing. According to one calculation someone of my body size burns about 1900Cal/day just breathing. Also, if you live where it's cold, you burn a lot more. And who knows if all that energy would go to fat.....

 

[FrustratedUser]

Originally posted by: 302efi
Thanks guys...I need to burn 120,000 kilocalories to get in shape:Q

210 000 here. :Q:Q:Q:Q
Asuming medium hard cardio on the bike for me burns 300 kcal/hour I need to be on the bike for 29 days straight.

 

[Peter]

6000 per kilo. Pure fat would be 9000, but in human-storage form, one gram of fat binds half a gram of water.

 

[ddviper]

Originally posted by: bobsmith1492
Whoa dude... we posted at the same time!

Actually your body burns a lot of energy just breathing. According to one calculation someone of my body size burns about 1900Cal/day just breathing. Also, if you live where it's cold, you burn a lot more. And who knows if all that energy would go to fat.....

ahh ok ic, so it would take a lot more cals to store up a pound of fat

 

[Peter]

The point is that every gram of fat you're OVEReating goes straight to storage. And, since most of the immediate power usage is taken from carbohydrates (and no, "low carb" diet isn't shifting that), you're not using a lot of fat during the day unless you put some (endurance) exercising into it. Even then, you won't get your body to cover more than half its energy expenditure from fat.

 

[res0n0xg]

just cut the fat out with a knife, no you can light it on fire with some gasoline afterwards and your still "burning" away that fat right?

 

[TimothyX]

Originally posted by: res0n0xg
just cut the fat out with a knife, no you can light it on fire with some gasoline afterwards and your still "burning" away that fat right?

.....r-i-g-h-t.

 

[Gnarly]

There's always the Lipo. Then you might make some soap, like in that movie fight club. Add a little spice and some aroma and you've got yourself some return on the food investment.

 

[Calin]

The dietary calories per gram of fat (9 cal) takes into account the energy needed to ingest/process/... it. For the fat that is already in organism, you should consider a bit more. Also, as Peter said, reduce the amount of water in fat storage. But the calculations are mostly correct, and good for just a physics problem.
Also, some energy is used by the body to heat itself (and the surroundings). This is called metabolism, and I think the metabolism combined with breathing (not only breathing as bobsmith1492 said)

 

[Peter]

Pure fat (the material) is 9 kcal per gram. Yes there is a certain amount of energy involved in getting that into storage, but this isn't in those 9 kcal. One gram of body fat tissue contains 6 kcal, because of the water tied into it.

 

[ribbon13]

If you want to burn fat quickly get your body into ketosis.

 

[Peter]

That's a myth. Recent - independent, not billion-dollar-diet-book-industry funded - research has shown the effect of the "Atkins" (South Beach, Low Carb, Blah Blah) diets to fuel the rapid weight loss from the strain put on the metabolism by the protein overkill, not the lack of carbohydrates or any other of the reasoning Dr. Atkins has been using. He made a correct observation, but came up with all-wrong explanations. Ketosis is just a way to ruin your kidneys faster - and it actually puts the brakes on your physical capabilities since, like it or not, the human body is primarily a carbohydrate burner. There are no tricks to make it run on fat alone whilst maintaining a remotely comparable amount of power - if anyone had come up with one, then the world of endurance sports would have had another revolution (after the one in the 1960s when it was discovered that it was the pasta that made the italian cyclists so much better, whilst everyone else still thought that Steak Power was the right thing).

Have carbs, exercise lots, burn fat. Most effective, and most healthy.

 

[Gibsons]

That's a myth. Recent - independent, not billion-dollar-diet-book-industry funded - research has shown the effect of the "Atkins" (South Beach, Low Carb, Blah Blah) diets to fuel the rapid weight loss from the strain put on the metabolism by the protein overkill, not the lack of carbohydrates or any other of the reasoning Dr. Atkins has been using.

Just speaking anecdotally, I think some of the effect is that it's an easy way to cut some calories. I noticed while my friends are on one of these diets, they'll eat the enchilada, but not the rice and beans for example. Certainly not the ideal way to cut calories, but I guess it's better than nothing... maybe....

Have carbs, exercise lots, burn fat. Most effective, and most healthy.

yep.

 

[nyarrgh]

So, is it better to exercise somewhere hot, where you will sweat. or somewhere cold, where your body needs to burn more to keep your body temperature constant?

 

[Gibsons]

Without researching this (ie, this is just an off the cuff opinion) if you're exercising fairly rigorously, you generate enough heat to keep warm in all but the very coldest climates... you don't burn any extra calories to keep warm. On the other hand, a colder environment might mean that you can exercise more/harder and thereby burn more calories. Running 10 miles is easier when it's 42F out than when it's 100F, but the caloric expenditure is probably about the same.

As someone already said, when you're not exercising you'll burn more calories in a colder climate.