title: The Validity of US Nutritional Surveillance: USDA's Loss-Adjusted Food Availability Data Series 1971-2010.
abstract: The purpose of this study was to examine the validity of the 1971-2010 United States Department of Agriculture's (USDA's) loss-adjusted food availability (LAFA) per capita caloric consumption estimates. Estimated total daily energy expenditure (TEE) was calculated for nationally representative samples of US adults, 20-74 years, using the Institute of Medicine's predictive equations with "low-active" (TEE L-ACT) and "sedentary" (TEE SED) physical activity values. TEE estimates were subtracted from LAFA estimates to create disparity values (kcal/d). A validated mathematical model was applied to calculate expected weight change in reference individuals resulting from the disparity. From 1971-2010, the disparity between LAFA and TEE L-ACT varied by 394kcal/d-(P < 0.001), from -205kcal/d (95% CI: -214, -196) to +189kcal/d (95% CI: 168, 209). The disparity between LAFA and TEE SED varied by 412kcal/d (P < 0.001), from -84kcal/d (95% CI: -93, -76) to +328kcal/d (95% CI: 309, 348). Our model suggests that if LAFA estimates were actually consumed, reference individuals would have lost ~1-4kg/y from 1971-1980 (an accumulated loss of ~12 to ~36kg), and gained ~3-7kg/y from 1988-2010 (an accumulated gain of ~42 to ~98kg). These estimates differed from the actual measured increments of 10kg and 9kg in reference men and women, respectively, over the 39-year period. The USDA LAFA data provided inconsistent, divergent estimates of per capita caloric consumption over its 39-year history. The large, variable misestimation suggests that the USDA LAFA per capita caloric intake estimates lack validity and should not be used to inform public policy.
authors.forename: Edward
authors.initials: E
authors.lastname: Archer
authors.forename: Diana M
authors.initials: DM
authors.lastname: Thomas
authors.forename: Samantha M
authors.initials: SM
authors.lastname: McDonald
authors.forename: Gregory
authors.initials: G
authors.lastname: Pavela
authors.forename: Carl J
authors.initials: CJ
authors.lastname: Lavie
authors.forename: James O
authors.initials: JO
authors.lastname: Hill
authors.forename: Steven N
authors.initials: SN
authors.lastname: Blair
mesh_terms: D000328:Adult; D000368:Aged; D000886:Anthropometry / Q000379:methods; D001835:Body Weight / Q000502:physiology; D002149:Energy Intake / Q000502:physiology*; D004734:Energy Metabolism / Q000502:physiology*; D015444:Exercise / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D009749:Nutrition Surveys; D050177:Overweight / Q000503:physiopathology*; D011159:Population Surveillance; D014481:United States; D055815:Young Adult