T Nation

KCals or Just Cals?

Can someone please explain to me why sometimes I see people talking about “kcals” and sometimes it’s just “cals”. For instance, why do I see on a nutritional label a serving listed as 200 calories, then someone else will refer to that exact same thing and say it contains 200 kcals?

99% of the time when someone is saying calories they actually mean kcals.

Any label on food items are measured in kcals.

fun fact: a calorie is the amount of energy needed to raise 1g of water by 1 degree Celsius.

[quote]ajweins wrote:
99% of the time when someone is saying calories they actually mean kcals.

Any label on food items are measured in kcals.[/quote]

Yep. An actual calorie is 1/1000 of a kilocalorie. Somewhere along the line people got lazy and started to refer to kilocalories as calories.

The point is, nobody actually talks about calories. So whether they say kilocalories or calories, they mean the same thing.

Ok so if I thought I was eating 4000 calories a day I’m actually eating 4 000 000?

The two are usually differentiated in chemistry as Calories (kcal) and calories. Just imagine reading the nutrition facts for a Snickers bar and seeing 320000 calories on the label.

[quote]Peot wrote:
Just imagine reading the nutrition facts for a Snickers bar and seeing 320000 calories on the label. [/quote]

Well it sure would make bulking a whole lot easier.

There are actually two definitions of the word “calorie” and it depends how you spell it.

With a lower-case ‘c’ it basically means what you see listed. EX: 100 calories = 100. Simple.

With an upper-case ‘C’ it is an abbrev. for kCal or 1,000 calorie. EX: 1 Calorie = 1,000 calories.

Somewhere in the midst of the “Nutrition Data” information thing that started years back they made the choice of putting 1 calorie equal to 1,000 calorie.

When people put “kcal” they are being technically correct.

It is more complicated that what has been previously posted.

I don’t have long to post right now but I will try and then come back later.

  1. Protein, Fat, and Carbs have burned at separate rates.

Carbohydrates: 1 g = 4 kcals
Protein: 1 g = 4 kcal
Fat: 1 g = 9 kcal

You would have to know how many grams of each nutrient you ate to calculate your total Kcal consumed.

Now determining how many Kcal you need is hard to do unless you are readily able to measure your VO2 max.

That being said you can get a close estimate if you have the following:

  1. Resting metabolic rate (RMR)
  2. Thermogenic effect of food you eat each day (TEF)
  3. Thermogenic effect of exercise (TEE)

Gotta run, class. I will resume in the next 24hr.

Always wrap your rascal!

[quote]hardgnr wrote:
Peot wrote:
Just imagine reading the nutrition facts for a Snickers bar and seeing 320000 calories on the label.

Well it sure would make bulking a whole lot easier.[/quote]

Good Christ - I had to laugh at that.

DJ

[quote]JGerman wrote:
It is more complicated that what has been previously posted.

I don’t have long to post right now but I will try and then come back later.

  1. Protein, Fat, and Carbs have burned at separate rates.

Carbohydrates: 1 g = 4 kcals
Protein: 1 g = 4 kcal
Fat: 1 g = 9 kcal

You would have to know how many grams of each nutrient you ate to calculate your total Kcal consumed.

Now determining how many Kcal you need is hard to do unless you are readily able to measure your VO2 max.

That being said you can get a close estimate if you have the following:

  1. Resting metabolic rate (RMR)
  2. Thermogenic effect of food you eat each day (TEF)
  3. Thermogenic effect of exercise (TEE)

Gotta run, class. I will resume in the next 24hr.

Always wrap your rascal!

[/quote]

The OP asked the difference between cals and kcals. He did not ask about macronutrients, vo2 maxes, metabolic rates, or the thermogenic effect of food.

I did chuckle at the “wrap your rascal” part, however.

[quote]ktennies wrote:
JGerman wrote:
It is more complicated that what has been previously posted.

I don’t have long to post right now but I will try and then come back later.

  1. Protein, Fat, and Carbs have burned at separate rates.

Carbohydrates: 1 g = 4 kcals
Protein: 1 g = 4 kcal
Fat: 1 g = 9 kcal

You would have to know how many grams of each nutrient you ate to calculate your total Kcal consumed.

Now determining how many Kcal you need is hard to do unless you are readily able to measure your VO2 max.

That being said you can get a close estimate if you have the following:

  1. Resting metabolic rate (RMR)
  2. Thermogenic effect of food you eat each day (TEF)
  3. Thermogenic effect of exercise (TEE)

Gotta run, class. I will resume in the next 24hr.

Always wrap your rascal!

The OP asked the difference between cals and kcals. He did not ask about macronutrients, vo2 maxes, metabolic rates, or the thermogenic effect of food.

I did chuckle at the “wrap your rascal” part, however.
[/quote]

Okay, well I’ll assume I was going too in depth about this so I will just wrap it up with what I have already posted.

Carbohydrates: 1 g = 4 kcals
Protein: 1 g = 4 kcal
Fat: 1 g = 9 kcal

If you have a shake with 40g of Protein, 4 g of fat, and 3 g of carbs you would have (404)+(49)+(3*4)=208 kcals (energy)

Depending on you age, weight, gender, exercise intensity and duration you can determine how many kcals you burn (expend) during exercise and your ‘normal daily activity’.

If you burn more kcals, you are at a deficit and if you eat more you are at a surplus.

Hope it makes sense.