Consumption data dietary surveys

The food diary method of collecting food consumption data requires survey participants to maintain a journal of the foods they consume. The food diary methodology is much more rigorous than the dietary recall. One variation of the food diary method requires survey participants to measure (perhaps by weighing) the amount of food they consume. The UK food consumption surveys use the food diary technique, and participants are required to weigh the amount of food that is consumed [ 15,16,17,18]. 

These are estimates of dietary exposure to inorganic contaminants for individuals who eat average amounts of food (i.e. mean consumers) and those who eat more than average (i.e. upper range (97.5th percentile) consumers) and are based on consumption data from the UK National Adult Dietary Survey (NADS).4 They are calculated using the mean upper bound concentrations of specific contaminants in each food group and the consumption data from the NADS. Consumer exposure estimates are less suitable for following trends in exposure than population estimates as they are based on consumption data from the NADS which was carried out only once in 1986 and 1987 and is not updated... 

Dietary exposure to pesticides (or to xenobiotics in general) is determined by calculating the product of the amount of chemical in or on the food and the total quantity of food consumed. The quantity of chemical potentially consumed in foods can be estimated from data obtained from residue field trials, metabolism studies, and/or monitoring data. Information from these sources is then analyzed with one of several available models containing food consumption factors from surveys conducted by the United States Department of Agriculture (USDA). For calculation of... 

The intake estimates are based on dietary intake data collected in the Danish nationwide food consumption survey of 2000-2002 [3]. The food consumption data were sampled throughout the 3 year period in order to account for possible seasonal variations in dietary habits. The representative sample of Danes included... 

TABLE 9.5. Estimated Intakes by Infants (4-6 Years) of Cd, Hg, and Pb Using Age-Specific Consumption Data from the Danish Dietary Survey for the 2000-2002 Period... 

For a 4-6-year-old child however, the mean and 95th percentile of Pb intakes estimated on the basis of age-specific consumption data from the 2000-2002 dietary survey (Table 9.5) correspond to 13 and 20 percent of the PTWI value, respectively. 

Clearly, the data for food consumption is a very important component of the dietary exposure model. There are some differences in the approaches taken in the US and in the EU, although food consumption data are not collected or treated the same way across the EU. In addition to differences in survey design and collection methods, the organization of the data can also have an impact upon the dietary risk assessment. 

Food consumption surveys are often conducted using the dietary recall or food diary methodologies. In the dietary recall technique, either direct face-to-face interviews or telephone interviews may be used to obtain food consumption data. Consumption amounts frequently are estimated using standard equipment, pictures, and diagrams to aid participants in estimating the amount of food consumed. Data from such recall surveys may be used for both chronic and acute dietary risk assessment The food consumption surveys on which the US dietary risk assessment models are based are of the dietary recall type [14]. 

Several assessments were conducted to illushate the impact of different procedures on dietary risk assessment. In all cases, consumption data from the UK surveys were used. One of the differences between the US and the EU is the food consumption data. However, conducting assessments with both US and UK food consumption data will confound the comparisons, so the assessments will be run using only the UK food consumption data. All exposure estimates are presented as percent of the chronic Reference Dose (cRiD) of 0.005 mg/kg bw/day or the acute Reference Dose (aRfD) of 0.01 mg/kg bw/day (both toxicity values are hypothetical for illushative purposes). 

Plasma and urinary levels of pantothenic acid have been measured in dietary surveys as well as in controlled studies of the vitamin deficiency. One fairly recent study with human subjects involved the feeding of a pantothenic acid-free diet for 9 weeks. The urinary pantothenic acid levels (4-6 mg/day) in vitamin-sufficient subjects were roughly half that of the intake (10 mg/day). With consumption of the vitamin-free diet, urinary pantothenic acid levels gradually declined to about 0.8 mg/day over the 9-week period (Fry et ai., 1976). Both urinary and blood serum levels of pantothenate have been used to assess dietary status. Values from urinary measurements seem to be somewhat better correlated with intake of this vitamin, than blood measurements data (Berg, 1997). 

Despite a growing visibility of and increasing consumer interest in tree nnts, as well as a greater availability of information on the health effects of higher nut consumption, there is very little objective and reliable information on nut intake profiles and qualitative and quantitative differences in nut consumption patterns globally. Most descriptive information on nut consumption has been based on estimates from food disappearance or market data rather than on individual dietary intakes. In many dietary surveys, questions on nut intake have been asked in insufficient detail or not at all. 

AFBi dietary exposure estimates were assessed in Japan based on food consumption data from the 2005 National Health and Nutrition Survey for 2 consecutive days (17 827 individuals). Surveillance data on AFBi concentration levels were available from a retail food survey, with samples purchased in a random manner from local supermarkets and small retail shops in all parts of Japan from the summer of 2004 to the winter of 2006 (Sugita-Konishi et al., 2007). Foods analysed included peanut, peanut butter, chocolate, pistachio, spices, almond, job s tears tea and buckwheat. A probabilistic approach was used to simulate the dietary exposure distributions in each age group with three different scenarios of MLs of AFT in tree nuts (10, 15 and 20 pg/kg), following the same methodology as described previously for the EFSA opinion and assuming a lognormal distribution for occurrence data. 

Source Pietinen, P (1982) Estimating sodium intake from food consumption data. Ann Nutr Metab, 26 90-99 Gregoy J, Foster K, Tyler H, Wiseman M. The Dietary and Nutritional Survey of British Aduits. HMSO (London, 1990). Sanchez-Castillo et at. (1996) Salt intake and blood pressure in rural and metropolitan Mexico. Archives of Medical Research 27 559-566. 

Cohort study data on population dietary exposure, dietary data from case-control studies and food consumption surveys... 

It has been well established that the ingestion of high dietary protein levels results in hypercalciuria in man, and that hypercalciuria is frequently accompanied by negative calcium balance (1-3). In a summary of data from nutritional surveys in the U.S., Pao (4J showed that dietary protein intake was well above the Recommended Dietary Allowances (RDA) for both men and women regardless of age (1). Although dietary calcium intakes are generally at the RDA for men, women below the age of 50 yr consume only 75% of the RDA (4J. Women above the age of 50 yr consume only two-thirds of the RDA for calcium (4). These low consumptions become critical when we consider the reduced ability for calcium absorption demonstrated in both men and women over the age of 60 yr (6). 

The FDA and EPA recognize that the diets of infants and children may differ substantially from those of adults and that they consume more food for their size than adults. As a result, they may be exposed to proportionately more residues. The FDA and EPA address these differences by combining survey information on food consumption by nursing infants, non-nursing infants, and children with data on residues to estimate their dietary exposure. The FDA and EPA also use this process to estimate exposure for other age groups, as well as several different ethnic groups and regional populations. 

According to the FDA Total Diet Study, in which dietary sodium and potassium intakes of three age groups of Americans were estimated from 1977 through 1980, cow s milk supplied 32 to 39% of the total sodium intake for infants, whereas the percentage for toddlers was much lower, 12 to 14% (Shank et al. 1982). Dairy products contributed about 10% of the sodium in the total diet consumed by adults. Data obtained from the National Health and Nutrition Examination Survey (HANES II) 1976-1980 (Carroll et al. 1983) reveal that the median daily consumption of sodium found naturally in food and added during... 

The UK Total Diet Study (TDS) relies on nationally representative information about the average food consumption by individual households researched in the UK National Food Survey (based on a survey of approximately 7000 households).2,3 Typical diets are constructed based on these data. Foodstuffs are purchased from retail outlets, then prepared and cooked in the normal manner. The individual foodstuffs are then usually combined into various groups of similar foods - for example cereals, green vegetables and fish - in the proportions eaten on average by consumers. Population dietary exposures can then be calculated using data from the TDS samples. 

As a result of the transfer of CDDs through the placenta to the fetus, by breast milk to infants and young children, and by lifelong dietary intakes from the consumption of meat, milk and dairy products, and fish, CDDs are found to be widespread in the adipose tissue of members of the general population (Orban et al. 1994). Human adipose samples from the recent 1987 NHATS Study provide a representative sample of CDD body burden in the general U.S. population (see Section 5.5.1). The average concentration of 2,3,7,8-TCDD in the U.S. population was estimated to be 5.38 pg/g ( 6%). The 1987 survey data clearly... 

In the UK, the Ministry of Agriculture, Fisheries, and Food and the Department of Health have conducted four sets of food consumption surveys between 1983 and 1997. These surveys make up the UK s National Diet and Nutrition Survey (NDNS) program. The UK has conducted surveys for infants [15], schoolchildren [16], adults [17], and most recently, yoimg people [18]. The food consumption information from these surveys is used for the various UK dietary exposure models, including the TMDI and the NESTI calculations. Elsewhere in the EU, dietary risk assessments may be based upon national food consultation surveys, such as the German data [20], or upon the regional diets... 

Dietary exposure is calculated as the very simple product of the amount of food consumed and the magnitude of the residue on the food. Unlike the food consumption value, which often is available from only one source (a government survey), the value of the residue portion of the equation may be provided from a wide variety of sources. These values range from the tolerance or MRL value, to data obtained from residue monitoring programs. The use to which various residue data may be put is often dictated by specific science policies within a given coimtry. 

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