Is dieting behaviour decreasing in young adolescents?

OBJECTIVE: To report trends in underweight, overweight and obesity in 12-15-year-old adolescents and examine changes in dieting behaviour, which have been less well documented. DESIGN: Comparison of two independent representative cross-sectional surveys. SETTING: Northern Ireland. SUBJECTS: Weight and height were objectively measured in 1324 boys and 1160 girls in 1996 and 1274 boys and 1374 girls in 2007. Participants reported whether they were following any particular diet including a self-proposed or prescribed weight-reduction diet. RESULTS: Overweight and obesity increased in girls from 15 % to 23 % and 2 % to 6 %, respectively. Increases were more modest in boys with overweight increasing from 13 % to 18 % and obesity from 3 % to 6 %. The proportion of underweight adolescents decreased from 9 % to 6 % in girls and 8 % to 5 % in boys. Evidence of social disparity was observed in girls from a manual socio-economic background, with overweight/obesity prevalence rates increasing from 21 % to 36 % compared with 15 % to 26 % in girls from a non-manual background. Despite these trends fewer adolescents, in particular girls, reported following weight-reduction diets (14 % of overweight/obese girls in 2007 v. 21 % in 1996; 8 % of boys in 2007 v. 13 % in 1996). Of these girls, the proportion from a manual background following weight-reduction diets decreased from 25 % to 11 %. CONCLUSIONS: Overweight and obesity are continuing to increase in adolescents despite government and media awareness strategies. There also appears to be reduced dieting behaviour, despite increasing body weight, particularly in girls from manual socio-economic backgrounds.

Dietary patterns and bone mineral status in young adults: the Northern Ireland Young Hearts Project.

Studies of individual nutrients or foods have revealed much about dietary influences on bone. Multiple food or nutrient approaches, such as dietary pattern analysis, could offer further insight but research is limited and largely confined to older adults. We examined the relationship between dietary patterns, obtained by a posteriori and a priori methods, and bone mineral status (BMS; collective term for bone mineral content (BMC) and bone mineral density (BMD)) in young adults (20-25 years; n 489). Diet was assessed by 7 d diet history and BMD and BMC were determined at the lumbar spine and femoral neck (FN). A posteriori dietary patterns were derived using principal component analysis (PCA) and three a priori dietary quality scores were applied (dietary diversity score (DDS), nutritional risk score and Mediterranean diet score). For the PCA-derived dietary patterns, women in the top compared to the bottom fifth of the 'Nuts and Meat' pattern had greater FN BMD by 0·074 g/cm(2) (P = 0·049) and FN BMC by 0·40 g (P = 0·034) after adjustment for confounders. Similarly, men in the top compared to the bottom fifth of the 'Refined' pattern had lower FN BMC by 0·41 g (P = 0·049). For the a priori DDS, women in the top compared to the bottom third had lower FN BMD by 0·05 g/cm(2) after adjustments (P = 0·052), but no other relationships with BMS were identified. In conclusion, adherence to a 'Nuts and Meat' dietary pattern may be associated with greater BMS in young women and a 'Refined' dietary pattern may be detrimental for bone health in young men.

Homocysteine and related B-vitamin status in coeliac disease: Effects of gluten exclusion and histological recovery.

OBJECTIVE: Hyperhomocysteinaemia is considered to be a risk factor for cardiovascular disease (particularly stroke) and has been implicated in recurrent miscarriage and osteoporotic fracture, recognized manifestations of coeliac disease (CD). The objective of this study was to compare plasma homocysteine levels and biomarker status of metabolically related B vitamins (folate, vitamin B(12), B(6) and riboflavin) in treated and untreated CD patients and healthy controls. MATERIAL AND METHODS: CD patients attending a clinic for either initial or follow-up biopsy (at least 12 months after commencing a gluten-free diet) were categorized into three groups: 1) newly diagnosed (untreated; n=35); 2) persistent villous atrophy (VA) at follow-up (n=24) or 3) recovered VA at follow-up (n=41). Blood samples were analysed for plasma homocysteine, serum and red cell folate and serum vitamin B(12) levels, and for plasma pyridoxal 5-phosphate (PLP, vitamin B(6)) and riboflavin (vitamin B(2)) status. RESULTS: Homocysteine concentrations were significantly higher (p=0.05) and red cell and serum folate significantly lower (p<0.001) in untreated patients compared with controls, while all three reached normal levels in recovered VA patients. Although untreated and persistent VA patients tended to have lower B(12) levels, these did not reach significance. There was no evidence of compromised B(6) or riboflavin status, even in untreated CD patients. Homocysteine concentrations were inversely associated with both serum (r=-0.421; p<0.001) and red cell (r=-0.459; p<0.001) folate and with serum vitamin B(12) (r=-0.353; p=0.001). CONCLUSIONS: Gluten exclusion in CD improves folate status and normalizes homocysteine concentrations. Reducing the risk of homocysteine-related disease may be another reason for aggressive diagnosis and treatment of CD.