Maximizing bone mineral accrual to attain an optimal peak bone mass (PBM), particularly during adolescence, appears to be an effective protective strategy in the prevention of osteoporosis. This study aimed to evaluate the influence of physical activity (PA), fat mass (FM), lean mass (LM), body mass index (BMI), calcium, or combination of vitamin D supplement intake, smoking and alcohol drinking status on bone health assessed by calcaneus quantitative ultrasound (QUS) in a healthy adolescent population. The participants comprised of 920 male and female secondary school adolescents aged 15–17 years old. Quantitative ultrasound measurements of the left heel were performed using Lunar Achilles EX II, which included results of broadband ultrasound attenuation (BUA), speed of sound (SOS), and a calculated stiffness index (SI). Multivariable linear regression analyses revealed that—PA was positively associated with all three QUS indices in both genders; BMI was positively associated with SI and SOS in females; LM was positively associated with BUA in both genders; and FM was negatively associated with SI in females. These variables accounted for 32.1%, 21.2% and 29.4% of females’ SOS, BUA and SI variances (p<0.001), respectively and 23.6%, 15.4% and 17.2% of males’ SOS, BUA and SI variances (p<0.001), respectively. Promoting health benefits from physical activity could influence bone status and consequently improve PBM, which is a potent protective determinant against osteoporosis in adulthood.

The repeatability of most questionnaires utilized in previous studies related to the consumption of dietary supplements (DS) among youth has not been well documented. Thus, a simple and easy-to-administer questionnaire to capture the habitual use of DS in the past one year known as the dietary supplement questionnaire (DiSQ) was developed and supported with external reliability evaluation. Analyses were done based on a convenience sample of 46 secondary school students. To elicit information regarding the intake of DS, the questionnaire was partitioned into two domains. The first domain was used to identify vitamin/mineral (VM) supplements, while the second domain was utilized to identify non-vitamin/non-mineral (NVNM) supplements. Cohen’s kappa coefficient (k) was used to evaluate the test–retest reliability of the questionnaire. Questionnaire administration to the respondents was done twice whereby a retest was given two weeks after the first test. Between test and retest, the reliability of individual items ranged from moderate to almost perfect for the VM (k = 0.53–1.00) and NVNM (k = 0.63–1.00) domains. None of the items had “fair” or ”poor” agreement. Various correlation coefficients can be obtained for the DiSQ but are generally reliable over time for assessing information on the consumption of supplements among the adolescent population.

Objective: Misreporting of energy intake (EI) in nutritional epidemiology is common and even severe among adolescents. Thus, the current study aims to examine the presence, bias and impact introduced by implausible reporters. Design: Cross-sectional. Setting: Central and eastern regions of Peninsular Malaysia. Participants: A stratified random sampling was employed to select 917 secondary school-going adolescents (aged 15–17 years). Results: The prevalence of under-reporters was 17·4 %, while no over-reporters were identified. Under-reporters had higher body composition and lower dietary intakes (except for vitamin C, Cr and Fl) compared with plausible reporters (P < 0·05). Adolescents with overweight and obesity had a higher odds of under-reporting compared with under-/normal weight adolescents (P < 0·001). In model 3, the highest regression coefficient (R2 = 0·404, P < 0·001) was obtained after adjusting for reporting status. Conclusions: Overweight and obese adolescents were more likely to under-report their food intake and consequently affect nutrient intakes estimates. Future analyses that include nutrient intake data should adjust for reporting status so that the impact of misreporting on study outcomes can be conceded and consequently improve the accuracy of dietary-related results.