Re: Need 2nd opinion about FDA Reference Values

[Guest guest]

Hi Tony:

About a year ago I asked (I think it was) nutritiondata.com a similar

question. The answer I got back seemed to amount to the following:

each of the different fat, protein and carbohydrate types (molecules)

contain different amounts of chemical energy per gram. The

multipliers 4 and 9 are just pretty decent overall averages. But if

a food contains significant amounts of molecules the energy content

of which are materially different from the averages, then its overall

caloric content will be materially different from that derived using

4 or 9.

They didn't provide a reference documenting this. But it certainly

seems like an explanation could make sense.

Rodney.

>

> Reference Values for Nutrition Labeling

> http://www.cfsan.fda.gov/~dms/flg-7a.html

>

> Based on a 2000 Calorie Intake

> Total Fat grams (g) 65

> Total carbohydrate grams (g) 300

> Fiber grams (g) 25

> Protein grams (g) 50

>

> ==

>

> By my calculation, the FDA reference values only add up to 1885

> Calories. Here is how I figure:

>

> Fat Calories = 9x65 = 586

> Carb Calories = 4x(total carbs - fiber) = 4x(300 -25) = 1100

> Protein Calories = 4x50 = 200

> Total = 1885 Calories

>

> It seems to me that if the FDA diet is 15%P, 30%F, 55%C with 25g of

> fiber, the number of grams for 2000 Calories should be P=75 g, F=66

g,

> Tot Carb = 300 g.

>

> Does anybody know why the official Reference values don't add up to

> 2000?

>

> Tony

>

[Guest guest]

Rodney,

Even if the chemical energy is slightly different from 4 kcal/g for

protein and carb, and 9 kcal/g for fat, this does not explain why most

of the missing 115 kcal (2000-1885) are from ~25 g of protein.

The only explanation that makes sense to me is that the minimum

protein requirement is 0.8 g per kg of body weight, and a 150 lb

person (68 kg) requires 54 g of protein which rounds to 50 g. I think

that the 50 grams represents some kind of implicit average minimum..

In any case, 115 kcal is only a ~5% difference which is a small

quantity of food in real life (an extra apple, half a soda, a handful

of corn chips, etc.), but if those calories should be coming from

protein, this difference is more serious. A low reference value of

protein will guarantee that the general population will be deficient

in protein even if they are meeting 100% of the USDA standard.

What bothers me most is that if the government which sets the rules

cannot count calories properly, how can we expect the manufacturers to

do so?

> >

> > Reference Values for Nutrition Labeling

> > http://www.cfsan.fda.gov/~dms/flg-7a.html

> >

> > Based on a 2000 Calorie Intake

> > Total Fat grams (g) 65

> > Total carbohydrate grams (g) 300

> > Fiber grams (g) 25

> > Protein grams (g) 50

> >

> > ==

> >

> > By my calculation, the FDA reference values only add up to 1885

> > Calories. Here is how I figure:

> >

> > Fat Calories = 9x65 = 586

> > Carb Calories = 4x(total carbs - fiber) = 4x(300 -25) = 1100

> > Protein Calories = 4x50 = 200

> > Total = 1885 Calories

> >

> > It seems to me that if the FDA diet is 15%P, 30%F, 55%C with 25g of

> > fiber, the number of grams for 2000 Calories should be P=75 g, F=66

> g,

> > Tot Carb = 300 g.

> >

> > Does anybody know why the official Reference values don't add up to

> > 2000?

> >

> > Tony

> >

>

[Guest guest]

>

> Based on a 2000 Calorie Intake

> Total Fat grams (g) 65

> Total carbohydrate grams (g) 300

> Fiber grams (g) 25

> Protein grams (g) 50

>

>

My count shows 1985 calories, as the government figures don't make

any distinction between soluble and nonsoluble fibers, so the 4

calories per gram count towards the 1985 calorie total, or rounding

to 2000 as they like to do.

Regards,

Don White

Seguin, Tx

[Guest guest]

Don,

Dietary fiber is defined as consisting of indigestible complex

carbohydrates. The fact that fiber cannot be digested means that you

cannot get any calories from it. This is why you subtract the grams

of fiber from the total carbohydrates to calculate the calories from

carbs.

It is known that microbial fermentation in the colon transforms some

of the fiber into short-chain fatty acids which are absorbed by the

intestines, but I have never heard that this is a significant source

of calories.

Tony

>

>

> >

> > Based on a 2000 Calorie Intake

> > Total Fat grams (g) 65

> > Total carbohydrate grams (g) 300

> > Fiber grams (g) 25

> > Protein grams (g) 50

> >

> >

> My count shows 1985 calories, as the government figures don't make

> any distinction between soluble and nonsoluble fibers, so the 4

> calories per gram count towards the 1985 calorie total, or rounding

> to 2000 as they like to do.

>

> Regards,

> Don White

> Seguin, Tx

>