Irma Venter

Nutritional contribution of street foods to the diet of people in developing countries: a systematic review

OBJECTIVE To review studies examining the nutritional value of street foods and their contribution to the diet of consumers in developing countries. DESIGN The electronic databases PubMed/MEDLINE, Web of Science, Cochrane Library, Proquest Health and Science Direct were searched for articles on street foods in developing countries that included findings on nutritional value. RESULTS From a total of 639 articles, twenty-three studies were retained since they met the inclusion criteria. In summary, daily energy intake from street foods in adults ranged from 13 % to 50 % of energy and in children from 13 % to 40 % of energy. Although the amounts differed from place to place, even at the lowest values of the percentage of energy intake range, energy from street foods made a significant contribution to the diet. Furthermore, the majority of studies suggest that street foods contributed significantly to the daily intake of protein, often at 50 % of the RDA. The data on fat and carbohydrate intakes are of some concern because of the assumed high contribution of street foods to the total intakes of fat, trans-fat, salt and sugar in numerous studies and their possible role in the development of obesity and non-communicable diseases. Few studies have provided data on the intake of micronutrients, but these tended to be high for Fe and vitamin A while low for Ca and thiamin. CONCLUSIONS Street foods make a significant contribution to energy and protein intakes of people in developing countries and their use should be encouraged if they are healthy traditional foods.

Dietary fat knowledge and intake of mid-adolescents attending public schools in the Bellville/Durbanville area of the city of Cape Town

AbstractObjectives: This survey primarily investigated the dietary fat knowledge and intake of 17-year-olds.Design: Cross-sectional descriptive survey.Setting and subjects: A random sample of 168 learners (89% response rate) attending public schools in the Bellville/Durbanville area participated with parental consent after the area manager of the Department of Education and the school headmasters granted approval to conduct the survey.Outcome measures: Both the test and the food frequency screener selected to assess learner dietary fat knowledge and intake respectively was pilot tested.Results: The learners mostly obtained average (46%) as well as below average (52%) dietary fat knowledge scores and mostly (61%) followed diets that were categorised as typically Western, quite high in fat. The learners’ interest in nutrition and their source of nutritional information, which was a subject presented at school, were positively associated with their dietary fat knowledge (p < 0.05) and intake (p < 0.05) and t...Abstract Objectives: This survey primarily investigated the dietary fat knowledge and intake of 17-year-olds. Design: Cross-sectional descriptive survey. Setting and subjects: A random sample of 168 learners (89% response rate) attending public schools in the Bellville/Durbanville area participated with parental consent after the area manager of the Department of Education and the school headmasters granted approval to conduct the survey. Outcome measures: Both the test and the food frequency screener selected to assess learner dietary fat knowledge and intake respectively was pilot tested. Results: The learners mostly obtained average (46%) as well as below average (52%) dietary fat knowledge scores and mostly (61%) followed diets that were categorised as typically Western, quite high in fat. The learners’ interest in nutrition and their source of nutritional information, which was a subject presented at school, were positively associated with their dietary fat knowledge (p < 0.05) and intake (p < 0.05) and their dietary fat knowledge was positively associated with their fat intake (p < 0.05). Conclusions: These mid-adolescents lack knowledge of dietary fat and are not consuming fats sparingly. However, their interest in nutrition, reliable nutritional information and dietary fat knowledge positively affected their fat intake. Interest in nutrition through nutrition and health education intervention initiatives should be cultivated among adolescents as it was identified as positively affecting both the dietary fat knowledge and intake of these adolescents.

Construction of a valid and reliable test to determine knowledge on dietary fat of higher-educated young adults

Abstract Objective: The construction of a questionnaire, in the format of a test, to determine knowledge on dietary fat of higher-educated young adults. Design: The topics on dietary fat included were in accordance with those tested in other studies. Forty multiple-choice items were drafted as questions and incomplete statements following the item construction rules. The items were reviewed by nutrition and food science professionals for content- and face-related evidence (n = 4 respectively) and by students representing the study population for face-related evidence (n = 16) of validity. Twenty items were removed as the panel questioned their relevance and replaced with 17 items reviewed by them. The items now largely focused on food sources of fat. These 37 items formed the preliminary test that was administered to two groups of higher-education students expected to differ in nutrition knowledge level. The completed and scored items were statistically analysed to determine which items could be retained for the test. Items meeting the item analysis criteria formed the test. The Mann-Whitney statistic was used to determine the construct-related evidence of validity and the Kuder-Richardson (K-R) 20 formula for the reliability of the test. Results: The 37-item preliminary test was completed by 99 and 87 students respectively forming the knowledgeable and less knowledgeable groups. Eighteen items remained after the statistical item analysis. Eight items did not meet the difficulty and discrimination index criteria respectively, nine the item-to-total correlation criteria and 13 the answer distribution criteria. The 18-item test was found to be reliable (K-R20 = 0.8997), as well as valid, since a significant difference (p < 0.001) in knowledge was found between the groups in the expected direction. Conclusion: The test can be used to compare the knowledge scores of groups and of individuals as it met the reliability coefficient of 0.75 and 0.85 respectively to make such score decisions.

South African dietary total antioxidant capacity based on secondary intake data in relation to dietary recommendations

Abstract Objective: In this exploratory study, the average adult South African dietary total antioxidant capacity (TAC) was estimated using secondary data and was evaluated against that determined for dietary intake recommendations. Design: The average adult South African dietary TAC was estimated using a report published by the Department of Health that summarises food consumption studies conducted in South Africa between 1983 and 2000. This estimated adult South African dietary TAC was evaluated against that determined for dietary intake recommendations incorporating the five-a-day concept and the basic food groups and beverages (tea and coffee). Results: The average adult South African dietary TAC was estimated as 11 433 micromoles (µmoles) Trolox equivalents (TE)/person/day, with beverages (tea) being the main contributor (38.5%). The dietary TAC based on the recommended five-a-day concept and other dietary intake recommendations was 20 513 µmoles TE/person/day, with beverages again being the main contributor (47.8%). Conclusions: Compared to the TAC of the five-a-day concept and other dietary intake recommendations, the South African population consumes about half of this estimated TAC per day. It is especially in the vegetable group and beverages where actual consumption is well below the coupled TAC. Grains are the only food group where consumption is above the coupled TAC. The five-a-day concept is only the aim for minimum intake and not the ultimate goal. An increase in these foods, along with beverages (tea) and whole grains to the recommended servings, can uphold the dietary TAC and health benefits.

Use of dietary supplements, and awareness and knowledge of the recommended fruit and vegetable intakes and consumption of health food store customers in the Cape Town city bowl

Abstract Objectives: The objectives of this study were to determine the dietary supplement use and demographic characteristics of customers visiting health food stores in the Cape Town city bowl, and to determine their awareness and knowledge of the recommended fruit and vegetable intake servings and their fruit and vegetable consumption. Design and setting: A self-administered questionnaire was completed by customers visiting two health food stores in the Cape Town city bowl. Subjects: Participants were recruited systematically. One hundred and sixteen of the 146 invited customers participated in the survey (79.5%), but the sample consisted of 112 because four questionnaires were not completed fully. Results: The majority of the sample (81.3%) used supplements, and 79.1% of these were regular users. The demographics of the sample and of the supplement users were mainly female and white, with a higher education, and a younger age. Vitamin (63.2%), mineral (42.5%) and herbal (42.5%) supplements were consumed most. The two main reasons for use were to supplement the diet (68.1%) and to prevent disease (59.3%). A third of the sample (33.0%) was aware of the “5-a-day” concept, while only 21.4% understood the concept. Knowledge of the recommended daily fruit (92.0%) and vegetable (47.3%) intake servings was higher than the awareness of the “5-a-day” concept, although only 65.2% and 14.3% of the respondents consumed the recommended daily servings of fruit and vegetables respectively. Conclusions: The demographic profile of the supplement users was similar to that reported in other studies. Knowledge of the recommended daily fruit and vegetable intake servings was higher than the consumption behaviour, as fewer servings were consumed than were indicated should be consumed, especially regarding vegetable intake. More respondents who were aware of the “5-a-day” concept were consuming the recommended intake of five fruit and vegetables servings daily.