Caloric Accuracy & Under Reporting

[Guest guest]

from another discussion list I am on....

Many of us have heard the stories of 30+BMI clients

who report that they eat no more than 1,000- to 1,200

calories a day. When Dr. Heymsfield put 17

such clients (average BMI: 33) into his metabolic lab

he found that 16 of 17 had REEs ±15% of

predicted,()(Heymsfield) which is considered to be

within the normal range.([ii])(Buhl) Their initial

self-reported energy intake was 1,054 ±211 kcals/d,

while their measured intake was 2,227 ±647 kcals/d.

Other metabolic studies of subjects with

“self-reported diet resistance” have found comparable

underreporting of energy intake.([iii])(Lichtman)

In healthy people the “normal” range of measured REE

falls in a standard bell curve distribution with 80%

of measurements falling ±10% of predicted, and 95%

falling ±15% of predicted. (Note that Dr. Heymsfield’s

subjects fit this range). The remaining 5% fall within

±20% of predicted, which is considered to be either

high or low.(7)(DuBois) In this case “healthy” means

euthyroid, disease free and not on medications which

may affect REE.

Heymsfield’s study reminds us that underreporting of

energy intake is the norm rather than the exception.

Heymsfield’s subjects underreported an average of 53%.

The data indicate that most subjects underreport

energy intake; in general underreporting increases as

BMI increases;([vi])(Johansson) overweight/obese

persons may have intakes approximately 40% higher than

reported, while those with a £25 BMI underreport by

about 20%.18(Lichtman)

Subjects underreport for a variety of reasons, and we

clearly have much to learn in understanding this

phenomenon. The most obvious is that it’s difficult to

accurately estimate portions without weighing and

measuring. If records are written at the end of the

day, or the next day, incomplete recall contributes to

underestimation. There may also be psychosocial

motivations (“impression management,” the desire to

appear to be doing what is perceived to be expected)

as well as the unconscious process of

denial.(16)(Heymsfield) Some data indicates that

locally labeled baked goods frequently contain

significantly more calories than labeled

for,([vii],()[viii])(Young) therefore, in some

cases subjects may be regularly consuming mislabeled

food items.

Underreporting of energy intake represents a

significant challenge for nutrition professionals

attempting to facilitate weight loss. The problem: you

cannot help your client problem solve what has yet to

be acknowledged. Therefore, if the fallacy of

underreported intake cannot be “confronted” the path

forward is effectively blocked. Being confident in

your knowledge of REE supports nutrition professionals

in addressing underreporting of energy intake.

Physiologically plausible reported intakes should (at

minimum) fall 1.25 times REE, although the range for

low to moderately active individuals is usually 1.5 to

1.7.(14) (2002 NAS)

Heymsfield SB, Darby PC, Muhlheim LS, Gallagher D:

The calorie: myth, measurement, and reality. Am J Clin

Nutr. 1995;62:1034S-41S.

[ii] Buhl KM, Gallagher D, Hoy K, s DE:

Unexplained disturbance in body weight regulation:

Diagnostic outcome assessed by doubly labeled water

and body composition analyses in obese patients

reporting low energy intakes. J Am Diet Assoc.

1995;95:1393-1400.

[iii] Lichtman SW, Pisarska K, Berman ER, Pestone M:

Discrepancy between self-reported and actual caloric

intake and exercise in obese subjects. N Engl J Med.

1992;327:1893-1898.

[iv] enfield DC, Rowe WA, JS, Cooney RN.

Validation of several established equations for

metabolic rate in obese and non-obese people. J Am

Diet Assoc. 2003:103;1152-1159.

[v] In Press: J Am Diet Assoc. 2004 (new review of

predictive equations by the ADA Evidence Based Work

Group on Indirect Calorimetry).

[vi] Johansson L, Solvoll K, Bjorneboe G-EA, Drevon C.

Under- and overreporting of energy intake related to

weight status and lifestyle in a nationwide sample. Am

J Clin Nutr. 1998;68:266-74.

[vii] D, Heshka S, Sepulveda D, Heymsfield S:

Counting Calories--Caveat Emptor. JAMA.

1993;270:1454-1456.

[viii] Young L, Nestle M: Food labels consistently

underestimate the actual weights of single-serving

baked products. J Am Diet Assoc. 1995;95:1150-1151.