Assessing dietary intake in children and adolescents : considerations and recommendations for obesity research

Dietary intake and food habits are important contributors to the obesity epidemic. They are highly modifi able components of energy balance and are usually targeted in both obesity prevention and treatment programs. However, measurement of total diet creates challenges and can convey a large burden in terms of cost, technical expertise, impact on respondents and time. It is not surprising therefore that comprehensive reports of dietary intake in children are uncommon and, when reported, have limitations. The aim of this paper is to guide researchers and practitioners in selecting the most appropriate dietary assessment method for situations involving children and adolescents. This paper presents a summary of the issues to consider when choosing a method, a description of some of the more commonly used dietary assessment methods for young people and a series of case-studies to illustrate the range of circumstances faced when measuring dietary intake. We recommend that researchers consider the specifi c components of dietary intake addressed in their research and practice, and whether diet should be reported comprehensively or as targeted components. Other considerations include age, cognitive ability, weight status, physical activity level, respondent burden, and reliability and validity in the context of program goals and research questions. A checklist for selecting the appropriate dietary methodology is provided. This guide aims to facilitate the reporting of dietary intake and food habits in the context of obesity using valid and reliable measures, thus contributing to the evidence-base for nutrition policies and programs relating to obesity.

The association between perceived sweetness intensity and dietary intake in young adults

Individual differences in taste perception may influence dietary habits, nutritional status, and ultimately nutrition-related chronic disease risk. Individual differences in sweetness intensity perception and the relationship between perceived sweetness intensity, food behaviors, and dietary intake was investigated in 85 adults. Subjects (body mass index [BMI]= 21 ± 3, 21 ± 4 y) completed a food and diet questionnaire, food variety survey, 2 24-h food records, and a perceived sweetness intensity measurement using the general labeled magnitude scale (gLMS). There was interindividual variation in perceived sweetness intensity (0 to 34 gLMS units, mean 10 ± 7). One-way analysis of variance (ANOVA) revealed no difference between perceived sweetness intensity and degree of importance placed on not adding sugar to tea or coffee (P = 0.2) and the degree of importance placed on avoiding sugar-sweetened or fizzy drinks (P = 1.0). Independent t-test analysis revealed no significant association between perceived sweetness intensity and the food variety measure for sugar and confectionary intake (P = 0.6) and selected fruit and vegetable intake (P = 0.1 to 0.9). One-way ANOVA also demonstrated no difference between tertiles of sweetness intensity and BMI (P = 0.1), age (P = 0.3), and food variety score (P = 0.5). No correlation was observed with regards to perceived sweetness intensity and mean total energy (kJ) intake (r = 0.05, P = 0.7), percent energy from total fat, saturated fat, protein, carbohydrate, and grams of fiber (r =–0.1 to 0.1, P = 0.2 to 0.8) and also for intake of the micronutrients: folate, magnesium, calcium, iron, and zinc (r = 0.1 to 0.2, P = 0.1 to 0.4). Only modest correlations were observed between sodium (r = 0.3, P < 0.05), vitamin C (r = 0.3, P < 0.05), and potassium (r = 0.2, P < 0.0) intake and perceived sweetness intensity. Overall, perceived sweetness intensity does not appear to play a role in food behaviors relating to sugar consumption and dietary intake in adults.

Dietary intake of fish and PUFA, and clinical depressive and anxiety disorders in women

Fish and PUFA consumption are thought to play a role in mental health; however, many studies do not take into account multiple sources of PUFA. The present study analysed data from a sample of 935 randomly selected, population-based women aged 20–93 years. A validated and comprehensive dietary questionnaire ascertained the consumption of n-3 and n-6 PUFA. Another assessed fish and energy intake and provided data for a dietary quality score. The General Health Questionnaire-12 (GHQ-12) measured psychological symptoms and a clinical interview (Structured Clinical Interview for DSM-IV-TR Research Version, Non-patient edition) assessed depressive and anxiety disorders. Median dietary intakes of long-chain n-3 fatty acids (310 mg/d) were below suggested dietary target levels. The only PUFA related to categorical depressive and anxiety disorders was DHA. There was a non-linear relationship between DHA intake and depression; those in the second tertile of DHA intake were nearly 70 % less likely to report a current depressive disorder compared to those in the first tertile. The relationship of DHA to anxiety disorders was linear; for those in the highest tertile of DHA intake, the odds for anxiety disorders were reduced by nearly 50 % after adjustments, including adjustment for diet quality scores, compared to the lowest tertile. Those who ate fish less than once per week had higher GHQ-12 scores, and this relationship was particularly obvious in smokers. These are the first observational data to indicate a role for DHA in anxiety disorders, but suggest that the relationship between DHA and depressive disorders may be non-linear.

The quality of dietary intake methodology and reporting in child and adolescent obesity intervention trials : a systematic review

Assessing dietary intake is important in evaluating childhood obesity intervention effectiveness. The purpose of this review was to evaluate the dietary intake methods and reporting in intervention studies that included a dietary component to treat overweight or obese children. A systematic review of studies published in the English language, between 1985 and August 2010 in health databases. The search identified 2,295 papers, of which 335 were retrieved and 31 met the inclusion criteria. Twenty-three studies reported energy intake as an outcome measure, 20 reported macronutrient intakes and 10 studies reported food intake outcomes. The most common dietary method employed was the food diary (n = 13), followed by 24-h recall (n = 5), food frequency questionnaire (FFQ) (n = 4) and dietary questionnaire (n = 4). The quality of the dietary intake methods reporting was rated as ‘poor’ in 15 studies (52%) and only 3 were rated as ‘excellent’. The reporting quality of FFQs tended to be higher than food diaries/recalls. Deficiencies in the quality of dietary intake methods reporting in child obesity studies were identified. Use of a dietary intake methods reporting checklist is recommended. This will enable the quality of dietary intake results to be evaluated, and an increased ability to replicate study methodology by other researchers.

Maternal dietary intake during pregnancy has longstanding consequences for the health of her offspring

Over the past 100 years, advances in pharmaceutical and medical technology have reduced the burden of communicable disease, and our appreciation of the mechanisms underlying the development of noncommunicable disease has broadened. During this time, a number of studies, both in humans and animal models, have highlighted the importance of maintaining an optimal diet during pregnancy. In particular, a number of studies support the hypothesis that suboptimal maternal protein and fat intake during pregnancy can have long-term effects on the growing fetus, and increase the likelihood of these offspring developing cardiovascular, renal, or metabolic diseases in adulthood. More recently, it has been shown that dietary intake of a number of micronutrients may offset or reverse the deleterious effects of macronutrient imbalance. Furthermore, maternal fat intake has also been identified as a major contributor to a healthy fetal environment, with a beneficial role for unsaturated fats during development as well as a beneficial impact on cell membrane physiology. Together these studies indicate that attempts to optimise maternal nutrition may prove to be an efficient and cost-effective strategy for preventing the development of cardiovascular, renal, or metabolic diseases.

Does personality affect dietary intake?

The purpose of this review is to evaluate the evidence for an association between the Big Five dimensions of personality, dietary intake, and compliance to dietary recommendations. Poor diet is a known risk factor for overweight and obesity and associated chronic lifestyle diseases and it has been proposed that personality may be linked to dietary choices. Findings from cross-sectional surveys from different countries and cultures show a positive association between Openness and consumption of fruits and vegetables and between Conscientiousness and healthy eating. Although no evidence has been found that personality dimensions are associated with adherence to dietary recommendations over time, Conscientiousness is associated with a number of prosocial and health-promoting behaviors that include avoiding alcohol-related harm, binge-drinking, and smoking, and adherence to medication regimens. With emerging evidence of an association between higher Conscientiousness and lower obesity risk, the hypothesis that higher Conscientiousness may predict adoption of healthy dietary and other lifestyle recommendations appears to be supported.

Dietary intake and dietary patterns related to blood pressure

 A sample of middle-aged Australians were consuming excessive amounts of salt from convenience foods and staple foods and consumed insufficient dietary potassium from fruits and vegetables. There needs increased awareness of the dietary sources of salt and potassium to assist in population blood pressure reduction.

Preventing mental health problems in offspring by targeting dietary intake of pregnant women

The concept of 'early life programming' considers the importance of very early environmental exposures throughout the gestational period on the subsequent health outcomes of offspring. The role of maternal dietary intake, specifically, has been highlighted after recent studies have shown maternal diet quality to predict mental health problems in offspring. Even in the pre-conception period, maternal nutrition can have permanent and sustained phenotypic consequences for offspring.

Pro-inflammatory dietary intake as a risk factor for CVD in men: a 5-year longitudinal study

Convincing evidence has identified inflammation as an initiator of atherosclerosis, underpinning CVD. We investigated (i) whether dietary inflammation, as measured by the 'dietary inflammatory index (DII)', was predictive of 5-year CVD in men and (ii) its predictive ability compared with that of SFA intake alone. The sample consisted of 1363 men enrolled in the Geelong Osteoporosis Study who completed an FFQ at baseline (2001-2006) (excluding participants who were identified as having previous CVD). DII scores were computed from participants' reported intakes of carbohydrate, micronutrients and glycaemic load. DII scores were dichotomised into a pro-inflammatory diet (positive values) or an anti-inflammatory diet (negative values). The primary outcome was a formal diagnosis of CVD resulting in hospitalisation over the 5-year study period. In total, seventy-six events were observed during the 5-year follow-up period. Men with a pro-inflammatory diet at baseline were twice as likely to experience a CVD event over the study period (OR 2·07; 95 % CI 1·20, 3·55). This association held following adjustment for traditional CVD risk factors and total energy intake (adjusted OR 2·00; 95 % CI 1·03, 3·96). This effect appeared to be stronger with the inclusion of an age-by-DII score interaction. In contrast, SFA intake alone did not predict 5-year CVD events after adjustment for covariates (adjusted OR 1·40; 95 % CI 0·73, 2·70). We conclude that an association exists between a pro-inflammatory diet and CVD in Australian men. CVD clinical guidelines and public health recommendations may have to expand to include dietary patterns in the context of vascular inflammation.

Factors related to the accuracy of self-reported dietary intake of children aged 6 to 12 years elicited with interviews: a systematic review

BACKGROUND: Understanding the relationship between children's dietary consumption and health is important. As such, it is crucial to explore factors related to the accuracy of children's reports of what they consumed. OBJECTIVE: The objective was to evaluate factors related to the accuracy of self-reported dietary intake information elicited by interview methods from children aged 6 to 12 years. METHODS: A systematic review of English articles using PsycINFO, PsycARTICLES, PsycEXTRA, PsycBOOKS, CINAHL Complete, Global Health, and MEDLINE Complete was performed. Search terms included interview, diet, children, and recall; studies were limited to those published from 1970 onward. Additional studies were identified using the reference lists of published articles. Studies that assessed children's dietary intake using direct observation, doubly labeled water, or the double-portion method and compared it with their recall of that intake (unassisted by parents) using an interview were included. RESULTS: The 45 studies that met the inclusion criteria showed that specific interview techniques designed to enhance children's recall accuracy had little effect. Rather, the timing of the interview appeared most important: The shorter the retention interval between children's consumption and their recall, the more accurate their memories. Children's age, body mass index, social desirability, food preferences, and cognitive ability were also related to accuracy. CONCLUSIONS: Factors related to the accuracy of children's dietary reporting should be taken into consideration when asking about consumption. Further research is required to examine whether other interview techniques, such as those developed to enhance children's recall of repeated staged events, can improve children's dietary reporting accuracy.

Maternal dietary intake and physical activity habits during the postpartum period: associations with clinician advice in a sample of Australian first time mothers

BACKGROUND: Numerous health benefits are associated with achieving optimal diet and physical activity behaviours during and after pregnancy. Understanding predictors of these behaviours is an important public health consideration, yet little is known regarding associations between clinician advice and diet and physical activity behaviours in postpartum women. The aims of this study were to compare the frequency of dietary and physical activity advice provided by clinicians during and after pregnancy and assess if this advice is associated with postpartum diet and physical activity behaviours.

METHODS: First time mothers (n = 448) enrolled in the Melbourne InFANT Extend trial completed the Cancer Council of Australia's Food Frequency Questionnaire when they were three to four months postpartum, which assessed usual fruit and vegetable intake (serves/day). Total physical activity time, time spent walking and time in both moderate and vigorous activity for the previous week (min/week) were assessed using the Active Australia Survey. Advice received during and following pregnancy were assessed by separate survey items, which asked whether a healthcare practitioner had discussed eating a healthy diet and being physically active. Linear and logistic regression assessed associations of advice with dietary intake and physical activity.

RESULTS: In total, 8.6 % of women met guidelines for combined fruit and vegetable intake. Overall, mean total physical activity time was 350.9 ± 281.1 min/week. Time spent walking (251.97 ± 196.78 min/week), was greater than time spent in moderate (36.68 ± 88.58 min/week) or vigorous activity (61.74 ± 109.96 min/week) and 63.2 % of women were meeting physical activity recommendations. The majority of women reported they received advice regarding healthy eating (87.1 %) and physical activity (82.8 %) during pregnancy. Fewer women reported receiving healthy eating (47.5 %) and physical activity (51.9 %) advice by three months postpartum. There was no significant association found between provision of dietary and/or physical activity advice, and mother's dietary intakes or physical activity levels.

CONCLUSIONS: Healthy diet and physical activity advice was received less after pregnancy than during pregnancy yet no association between receipt of advice and behaviour was observed. More intensive approaches than provision of advice may be required to promote healthy diet and physical activity behaviours in new mothers.