Hi all,

Been using fitday for ages. But I just noticed some weird numbers today, did a bit of math, and my thinking is that FitDay is calculating calories from carbs *including* fiber.

Basically, it seems it's doing 4 cals / g of non-fiber carbohydrate, and something around 1.8 - 1.9 cals / g of dietary fiber.

Is this correct? I was blown away because I was trying to hit macros for a program I am on that is specified with a macro breakdown and calorie total. If you multiply carb target x 4, protein target x4, and fat target x 9, it equals the target total calorie figure.

But I ate pretty close to that in the past couple days and realized I was hitting my calorie limit even though my fat grams were almost 14 grams lower than the target (and nothing was really over).

I realized in the end that FitDay doesn't subtract fiber grams from the total carbs. Which may be fair -- what is the research on this?

I read somewhere that the practical effect of fiber on metabolism is around 2 calories / g.

Anyone offer any insight?

P.S. Here is an example of a day that confuses me:

http://www.fitday.com/fitness/PublicJournals.html?Owner=ceefbake&Year=2008&Month=9&Day=26

Been using fitday for ages. But I just noticed some weird numbers today, did a bit of math, and my thinking is that FitDay is calculating calories from carbs *including* fiber.
From their FAQ:

Does grams of carbohydrates include grams of fiber?
Yes. However, FitDay also has a special nutrient called Carb - Fiber which gives you total grams of carbohydrates excluding grams of fiber.

I realized in the end that FitDay doesn't subtract fiber grams from the total carbs. Which may be fair -- what is the research on this?I briefly mentioned this in my sticky (http://forums.johnstonefitness.com/showthread.php?t=42001):

"Insoluble fiber passes through your body without being converted to a form that provides energy, or calories. Knowing this, the manufacturer may subtract the caloric value of the insoluble fiber (but not the soluble fibre) from the total calories figure."

I don't examine my Fitday numbers very carefully, so I'm not sure if Fitday calculates their soluble and insoluble fibre the same way.

See also this article: The Case of the Missing Calories (http://findarticles.com/p/articles/mi_m0820/is_/ai_18696320)

Of note:

If a product has 50 calories or fewer, the manufacturer must round off to the nearest multiple of five. If a product has more than 50 calories, the manufacturer must round off to the nearest multiple of 10

THE 9-4-4 NUMBERS that nutrition-savvy consumers can recite with the fluency of the alphabet are also approximations meant for rough calculations. For example, the notion that carbohydrates have four calories per gram is rounded up from 3.6. This explains the label on a can of Coca-Cola Classic. This product has no fat or protein and 39 grams of carbohydrates. Multiplied by 4, the soda appears to have 156 calories, but the label claims 140. Coca-Cola spokesperson George Barkley confirmed that the company reaches the 140 figure by multiplying the carbohydrate grams by 3.6. "Those 16 calories won't make a hill of beans in a diet," explains Kathleen Zelman, R.D., a Marietta, Georgia-based nutritionist and spokesperson for the American Dietetic Association. "People must believe the numbers on a label but accept that there is a margin of error." Protein tends to have 4.1 or 4.2 calories per gram, depending on the source.


So, if you want to be really specific, 100 grams of protein has about as many calories as 115 grams of fibre-free carbohydrate, or as many calories as 125 grams of carbohydrate, if 10 of those grams are insoluble fibre.

So some fiber isn't broken down at all. Then isn't that going to throw everything off? If you are trying to eat clean and get decent amounts of fiber, while keeping protein up I'd imagine you're gonna have a hell of a time keeping things accurate!

Yes, it's pretty much impossible to calculate your exact energy intake.
Things like glycemic load of the meal, timing around workouts, and other factors can affect your hormone levels, which will impact how efficiently your calories are converted to energy and stored as fat.

But it's pretty much impossible to calculate your exact energy expenditure too.

Turning down your thermostat or drinking lots of cold water could cause you to burn an extra 100 calories a day. Chewing gum or tapping your toes could burn that many too.

There's a lot of unrecordable stuff we just can't account for. Most of it is so small it's insignificant. At those precise levels (more accurate than within about 10% of your "true" intake and expenditure), meal timing and macronutrient splits likely have more of an impact than the amount of calories.