Re: Re: Need 2nd opinion about FDA Reference Values

[Guest guest]

Tony..

I think you will find your answer in the text below...

and it is in their allowable variance...

Jeff

http://www.cfsan.fda.gov/~dms/owg-rpt.html

c. Other Labeling Issues

The OWG considered comments from the FTC on the issues

of (1) reduced/fewer calorie comparisons, (2)

comparison to food of different portion size, (3)

comparison to food of different product type, and (4)

disclosure requirements for comparative claims.

Reduced/fewer calorie comparisons. The underlying

principle for FDA's regulation is that reductions be

significant compared to the reference food (21 CFR

101.60((4). FDA determined that percentage

reductions less than 25% were too small to be

meaningful because of normal product variability. Such

variability may be caused by factors such as: natural

nutrient variability of the food due to season of the

year, soil type, variety, and weather conditions;

variability in processing; rounding rules (e.g.,

rounding to the nearest 5 calories up to 50 calories

and to the nearest 10 calories above 50 calories);

analytical variance (ranging from +/- 3-4% to +/- 30 %

with an average variance of about +/- 15%); sampling

procedures; and shelf life and stability of nutrients

in the product.

As a result, 21 CFR 101.9(g) allows for a 20% excess

in the actual (analytical) nutrient content of

calories, sugars, total fat, saturated fat,

cholesterol or sodium of a product compared to the

declared nutrient values for that product (and

consequently the qualifying values for nutrient

content claims) before the food is considered to be

misbranded. Therefore, nutrient reductions less than

25% are virtually within the allowable product

variability and are not considered significant. The

minimum absolute reduction (e.g., equivalent to the

value of " low " ) was changed to permit claims compared

to reference foods that were not already " low " in the

nutrient because it was the agency's conclusion that

benefits derived from several servings of

nutritionally modified nutrient dense foods over a day

could have a significant impact provided that the

reduction was significant, i.e., 25 % or more. FDA

further concluded foods already " low " in that nutrient

were below the level at which the amount of nutrient

in the food becomes significant relative to the total

diet and therefore should not be used as reference

foods.

[Guest guest]

> 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

the estimate is 1.5-2.5 cal/g. So lets say 2. As

most american get in around 15 grams of fiber, its

around 30 calories. If you hit the RDA or 25, its 50

calories. If you hit the higher recommendations of

30-40 ish, its still only 60-80. So, for most people

it doesnt contribute many calories.

http://darwin.nap.edu/books/0309085373/html/349.html

Contribution of Fiber to Energy

When a metabolizable carbohydrate is absorbed in the

small intestine, its energy value is 16.7 kJ/g (4

kcal/g); when fiber is anaerobically fermented by

colonic microflora in the large intestine, short-chain

fatty acids (e.g., butyrate, acetate, and propionate)

are produced and absorbed as an energy source. Once

absorbed into the colon cells, butyrate can be used as

an energy source by colonocytes (Roediger, 1982);

acetate and propionate travel through the portal vein

to the liver, where propionate is then utilized by the

liver. Acetate can be metabolized peripherally. A

small proportion of energy from fermented fiber is

used for bacterial growth and maintenance, and

bacteria are excreted in feces, which also contain

short-chain fatty acids (Cummings and Branch, 1986).

Differences in food composition, patterns of food

consumption, the administered dose of fiber, the

metabolic status of the individual (e.g., obese, lean,

malnourished), and the digestive capability of the

individual influence the digestible energy consumed

and the metabolizable energy available from various

dietary fibers. Because the process of fermentation is

anaerobic, less energy is recovered from fiber than

the 4 kcal/g that is recovered from carbohydrate.

While it is still unclear as to the energy yield of

fibers in humans, current data indicate that the yield

is in the range of 1.5 to 2.5 kcal/g (Livesey, 1990;

et al., 1998).

[Guest guest]

Tony

I found this tonight on the USDA site and thought you

would appreciate it..

I multiplied protein, fat and carbohydrate values by

4-9-4, but my energy value is different from USDA's.

Why?

Calorie values are based on the Atwater system for

determining energy values. The factors used in the

calculation of energy in the database are given in the

food description file of the USDA Nutrient Database

for Standard Reference, Release 18. The basis and

derivation of these factors are described in

Merrill, A.L. and Watt, B.K. 1973. Energy Value of

Foods...Basis and Derivation. Agriculture Handbook No.

74. U.S. Government Printing Office. Washington, DC.

105p.

This reference is out of print, but a scanned copy is

viewable on our home page.

http://www.nal.usda.gov/fnic/foodcomp/Data/Classics/ah74.pdf

It may also be available at many university libraries.

The Atwater system uses specific energy factors which

have been determined for basic food commodities. These

specific factors take into account the physiological

availability of the energy from these foods. The more

general factors of 4-9-4 were developed from the

specific calorie factors determined by Professor

Atwater and associates. For multi-ingredient foods

which are listed by brand name, calorie values

generally reflect industry practices of calculating

calories from 4-9-4 kcal/g for protein, fat, and

carbohydrate, respectively, or from 4-9-4 minus

insoluble fiber. The latter method is frequently used

for high-fiber foods because insoluble fiber is

considered to provide no physiological energy. If the

calorie factors are blank or zero for an item in the

Database, energy was calculated by recipe from

ingredients or was supplied by the manufacturer.