Introduction
The dietary habits acquired in childhood affect the health of young adults in later years. Thus, dietary assessment can help young adults to monitor their food intake and ensure that it does not exceed their daily energy requirements. Evidence from epidemiologic studies shows that low physical activity and unhealthy eating habits are associated with disease conditions such as obesity and overweight (O’Connor, Yang, and Nicklas 2006). Biro et al. (2002: 526) suggest five factors, which should be considered when selecting a dietary assessment method. These include absolute intake vs. relative intake, the duration under consideration, the type of food, group vs. individual dietary needs and population characteristics.
Food Frequency Questionnaire (FFQ) is a common tool used to measure nutrient intake among participants; it has questions on one’s consumption frequency (food and beverage intake), food quantity and preparation methods over a past duration usually one month. However, this instrument has significant errors, as it is largely dependent on the participants’ memory (Palaniappan, Cue, and Gray-Donald 2003). Alternative methods involve the use of food diaries and 24-hour recalls. The use of food diary-based results is considered superior to the FFQ because they are open-ended and does not depend on the individual’s memory. A food diary or record also ensures a regulated food intake by a person at specific times to control weight. The aim of the proposed project is to measure the nutrient intake (macro- and micro-nutrients) of female students in their young adulthood based on the results of 3-day food diaries.
Types of Food Diaries/Records
A food record refers to a booklet with a description of the quantities and types of food nutrients, food supplements, and fluids/beverages an individual consumes over a specified duration. The duration often ranges from 3 days to 7 days (Biro et al. 2002: 528). Study subjects are required to enter the details of their nutrient intake, recipes, food preparation methods, quantity consumed and food brand names in the food diaries. In addition, the time and place of consumption as well as the actual name of the dish/meal are reported in the diaries. There are two approaches of preparing dietary records. The first one is the weighted food diary, whereby the exact intake is obtained from the subjects’ weighted intake (food and beverages) less any unconsumed food or beverage (Zimmerman and Snow 2009). While weighted food records yield detailed and accurate results, they are time consuming, labour intensive and expensive. The second approach is the estimating food record, which is based on the participants’ estimates of the food quantity consumed using plates, spoons and cups as measuring models. According to Palaniappan, Cue, and Gray-Donald (2003), instructing the participants on weighing procedures of their food and beverage intake can significantly improve the accuracy of the results. This study will use the second approach as it is relatively inexpensive and guarantees improved accuracy of the results.
Nutrient intake assessment among subjects raises two fundamental issues, namely, the exact time to record and the duration of recording. The most common recording periods are 7-day and 3-day periods. In research, the 3-day food diary is often the preferred assessment method, as it does not interfere with the subjects’ consumption habits. It also enhances the recruitment of subjects (Biro et al. 2002). However, short diaries raise concerns over whether they accurately represent the subjects’ habitual nutrient intake. In contrast, the 7-day diaries not only enhance participant compliance but they are also more accurate as the assessment covers the entire week, i.e., dietary assessment includes the records made in all the days of the week.
In 3-day diaries, the subject’s record the beverages and food intake in three consecutive days usually two week days and one weekend day. This study will use the participants’ Thursday, Friday, and Saturday food intakes to assess the young females’ dietary intake. In such assessment, the nutritionist uses specific software such as SPSS and CANDAT program to analyze the records to estimate the subjects’ carbohydrates, proteins, vitamins, fat, mineral nutrients and fibre intake (Presse et al. 2011). Food diaries also do not rely on the participants’ memory to obtain information about the frequency and quantity of nutrient intake (Zimmerman and Snow 2009). 3-day diaries are preferable to 7-day diaries as participants’ recording often declines when the participants have to record their intake for more than three days in a week.
Monitoring Food Intakes
Monitoring a population’s food intake helps individuals to control their dietary intake and maintain desirable body weights that are within healthy reference values as opposed to being overweight or obese (Presse et al. 2011). An individual’s intake correlates with his or her energy requirement. Thus, in the population context, some people may not be described as healthy because either their intake exceeds their energy requirements or their physical activity levels (PALs) are low. Zimmerman and Snow (2009: 75) define nutrient requirement as the amount of nutrients that meets the nutritional needs of a population or group. Therefore, monitoring the food consumption of a population helps to maintain body weights within healthy range of values. Furthermore, monitoring of nutrient intake based on the group-specific energy reference values would ensure that the population maintains desirable body weights.
Nutritional Needs for Young Healthy Adults
Young adults have a high nutrient and energy demands. At this stage, optimal nutrition is necessary for the young adults to attain full maturity and growth (Zimmerman and Snow 2009). Their nutritional needs are gender-specific. The recommended dietary allowances (RDAs) for young male and female adults (19-30 years) are as shown in table 1 below:
Table 1: The recommended dietary allowances (RDAs) for young adults
Source: Zimmerman and Snow (2009).
Subjects and Methodology
The proposed study will involve a prospective cohort approach. Young female adults (18-30 years) will be selected from Coventry University to participate in this research. The participants will be required to give a written consent before participating. They will then be instructed on how to complete the food diaries. According to O’Connor, Yang, and Nicklas (2006), eligible subjects should be healthy i.e., they should not be suffering from illnesses such as cancer, diabetes or stomach ulcers, which may affect their dietary intake. Moreover, pregnant women will be excluded from the study.
The dietary assessment will involve 3-day food diaries, which the subjects will be required to complete for a period of three days (Thursday, Friday, and Saturday). In literature, issues associated with reporting such as the ideal time of the day and the influence of seasons have been the centre of focus because they affect the accuracy of the assessment. In their study, Heaney et al. (1999) noted that more accurate food diaries could be achieved if the reporting is done on non-consecutive days (three-, five- and seven-day) as eating behaviour correlates with consecutive days. Therefore, the proposed study’s 3-day diaries will cover three non-consecutive days of the week to enhance subject compliance and accuracy of the reports entered on the diaries.
Heaney et al. (1999) suggest that a 3-day food record includes two working days and one day of the weekend as weekend days often have higher self-reports on nutrient (micro- and macro-nutrients) intake. It is believed that, for 3-day records, energy intake on Thursdays and Fridays can predict the weekend intake (Heaney et al. 1999). In the proposed study, the subjects will be required to complete their food diaries on a Thursday, a Friday, and a Saturday for one week.
A reminding call made to the subjects can improve the evaluation of nutrient intake using the 3-day dietary records (Presse et al. 2011). Women and overweight people often give biased reports or under-report their intake resulting to underestimation of their habitual intake. Thus, a reminder call made to female participants can improve the accuracy of the results. They will be required to use household items such as standard bowls, a ruler, spoons and glasses to estimate their food intake as the standardized measures facilitate nutrient analyses (Palaniappan, Cue, and Gray-Donald 2003: 233). They will be required to record their food and beverage intake over three non-consecutive days of the week. Completed diaries will then be returned to the researcher and analyzed using the dietary analysis packages, such as the CANDAT software, to determine consumption of nutrients among participants.
References
Biro, G., Hulshof, K., Ovesen, L., and Cruz, J. (2002) ‘Selection of methodology to assess food intake’. European Journal of Clinical Nutrition 56 (8), 25-32.
Heaney, R., Davies, M., Reckerand, R., and Packard, P. (1999) ‘Long-Term Consistency of Nutrient Intakes in Humans’. The Journal of Nutrition 120 (12), 869-875.
O’Connor, T., Yang, S., and Nicklas, A. (2006) ‘Beverage Intake Among Preschool Children and Its Effect on Weight Status’. Pediatrics 118 (4), 101-106.
Palaniappan, U., Cue, R., and Gray-Donald, K. (2003) ‘Implications of Day-to-Day Variability on Measurements of Usual Food and Nutrient Intakes’. The Journal of Nutrition 133 (1), 232-235.
Presse, N., Payette, H., Shatenstein, B., Greenwood, C., Kergoat, M., and Ferland, G. (2011) ‘A Minimum of Six Days of Diet Recording Is Needed to Assess Usual Vitamin K Intake among Older Adults’. The Journal of Nutrition 141 (7), 341-346.
Zimmerman, M., and Snow, B. (2009) An Introduction to Nutrition. New York: Prentice Hall.