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Validation Information: Oxford FFQ

Samaras 1998

Gene versus environment: The relationship between dietary fat and total and central abdominal fat

Objective: The influence of diet on body fat has not been quantified independently of genetic influences, although both are held to contribute to regulation of body fat stores. This study examined 1) the relationship between recent diet and total body and central abdominal fat in middle-aged female twins independent of genetic and important environmental factors and 2) evidence of interaction between diet and genetic predisposition.

Research Design And Methods: Measurements in 436 healthy female twins (aged 58 ± 10 years) included dietary intake by food frequency questionnaire (validated against a 7-day food diary, n = 162), BMI, total body and central abdominal fat by dual-energy X-ray absorpiometry, and environmental covariates (smoking habit, hormonereplacement, and physical activity) by standardized questionnaire. Dietary energy underreporters were excluded.

Results: Intake of dietary fat (total and subtype) and carbohydrates was not related to BMI or to total or central fat, confirmed in quintile analysis. With genetic and environmental factors controlled in 90 monozygotic pairs, differences in the intake of energy, fat, or protein were not related to intrapair differences in total and central body fat. However, a minor inverse relationship between carbohydrate intake and total adiposity was confirmed (r = -0.25, P = 0.02). In paired analyses, the twin with the higher intake of total sugars had significantly lower total body and central abdominal adiposity. There was no evidence of a gene-environment interaction between intake of fat or carbohydrates contributing to greater body fat mass in subjects genetically predisposed to obesity.

Conclusions: Using validated dietary measures and direct measures of body fat and excluding underreporters, no relationship between dietary fat and body fat was found in middle-aged women, particularly after controlling for genetic and some environmental factors. The role of dietary factors in determining total body and central abdominal fat appears to have been overestimated in past cross-sectional studies.

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Validation Information

Year of Publication

Tool Information

Dietary Exposure Measured
Full Nutrient, Food Groups
Tool Type
Food Frequency Questionnaire
Timeframe Tool Measures info
1 Year
Portion Size Measures info
'Medium servings' or specified units using household measures. 'Medium servings' were derived from experience with other dietary surveys and from published values (Crawley, 1988).
Reporting Method info
Usual; Retrospective
Format info
Supplements Measured
Not Reported
Administration Method info

Study Information

Study Location
London, England
Associated Nutrient Database
McCance & Widdowson's The Composition of Foods, 5th edition
Comparator Validated Against
Food Diary Estimated


Sample Size
Age of Population

Mean: 58 ± 10 years

Female Only
Other Notable Characteristics
Participants were twins.

Total number of nutrients validated: 5 info

Not all of the nutrients validated in the validation studies are included in the table below, as statistical data was only selected to be displayed for a number of nutrients, this included:

  • Energy
  • Fat
  • Saturated Fat
  • Mono-unsaturated Fat
  • Poly-unsaturated Fat
  • Carbohydrates
  • Protein
  • Sugar
  • Non‐starch polysaccharides(NSP)
  • Sodium
  • Calcium
  • Iron
  • Zinc
  • Retinol
  • Folate
  • Folic Acid
  • Vitamin B12
  • Vitamin C
  • Fruit & Vegetables
  • Urinary Nitrogen

To find information on the other validated nutrients please read the validation study.

  • Energy
  • Macronutrients: 4
  • Micronutrients: 0
Comparator Lifestage Sex Nutrient Measured info Mean Difference Standard Deviation info Correlation Coefficient info Cohen's Kappa Coefficient Percentage Agreement Percentage Agreement Categories info Lower Limits of Agreement Upper Limits of Agreement
Estimated Food Diary Adults Female Only Energy (kcal) 164 0.42 (P)
Energy (kJ) 686 0.42 (P)
Protein (g) 1.4 0.50 (P)
Fat (g) -0.3 0.46 (P)
Carbohydrates (g) 1.4 0.53 (P)
Total Sugars (g) 2 0.56 (P)

Some results have been calculated using statistical techniques based on the published data.

For further information on statistical terms click on Statistical tests used in validation studies

All correlations coefficients in the table are unadjusted unless stated otherwise. For adjusted correlation coefficients and other statistical methods used in the study e.g. paired t-tests, please read the validation articles.

  • # Adjusted
  • † Energy adjusted.
  • ‡ For loge-transformed, energy-adjusted nutrient intakes.
  • ^ Adjacent included.
  • ᵟ Participants provided identical responses.
  • (w) = Weighted.

Samaras K, Kelly PJ, Chiano MN, Arden N, Spector TD, Campbell LV. Genes versus environment: the relationship between dietary fat and total and central abdominal fat. Diabetes Care. 1998 Dec 1;21(12):2069-76.