Bárbara Santarosa Emo Peters

Prevalence of Vitamin D Insufficiency in Brazilian Adolescents

Background/Aims: Cutaneous sun exposure and dietary vitamin D intake are important determinants of vitamin D status. The objective of the present study was to evaluate the vitamin D status of a group of healthy adolescent students living in Brazil. Methods: One hundred and thirty-six adolescents, 64 boys and 72 girls, aged 16–20 years old, living in a rural town in the state of São Paulo, Brazil, participated in this study. Results: The mean dietary vitamin D intake was 140 (120–156) IU/day [3.5 (3.0–3.9) μg/day]. Only 14.9% of the students met the daily adequate intake recommendation of vitamin D. Only 27.9% practice physical activity outdoors and 17.6% of the adolescents apply sunscreen daily. The mean 25(OH)D concentration was 73.0 (22.0) nmol/l [29.2 (8.8) ng/ml]. Vitamin D insufficiency was observed in 60% of adolescents. Conclusions: The present study suggests that even in a sunny climate like Brazil the prevalence of vitamin D insufficiency in adolescents is high. Most likely this is due to low intakes of vitamin D in this group. Due to the limited extent of natural dietary sources of vitamin D, a policy of vitamin D food fortification should be considered in the future, and in the meantime greater use of vitamin D supplements in this population group should be encouraged to provide the increased amounts of this essential nutrient for optimal health.

Nutritional aspects of the prevention and treatment of osteoporosis

Osteoporosis is a global health problem characterized by low bone mass and microarchitectural deterioration of bone tissue with a consequent increase in bone fragility and susceptibility to fracture. Nutrition plays a critical role in reducing the risk of osteoporosis through its effect on all of these fragility factors, especially on the development and maintenance of bone mass. An adequate calcium, vitamin D and protein intake resulted in reduced bone remodeling, better calcium retention, reduced age-related bone loss, and reduced fracture risk. Recent evidence indicates that a healthy dietary pattern including dairy products (mainly fat free), fruit and vegetables and adequate amounts of meat, fish and poultry is positively related to bone health. Furthermore, mineral and vitamin supplementation should be closely monitored by health professionals since it could have adverse effects and be insufficient to ensure optimal protection of bone health.

The influence of breakfast and dairy products on dietary calcium and vitamin D intake in postpubertal adolescents and young adults

BACKGROUND Given the importance of both calcium and vitamin D for bone health and the high prevalence of vitamin D from around the world, the present study aimed to evaluate calcium and vitamin D intake in a group of healthy Brazilian adolescents and young adults and to examine the influence of breakfast and dairy products in the total intake of these nutrients. METHODS   One hundred and sixty adolescents and young adults, aged 16-20 years old, from a public school, participated in the present study. Three-day dietary records were used to assess calcium and vitamin D intakes. Serum 25(OH)D levels were measured using a radioimmunoassay kit. The results were expressed as the mean (SD). RESULTS Only 3.8% of the subjects met the daily adequate intake recommendation for calcium, and none for vitamin D [682.2 (132.2)mg day(-1) and 124.0 (28.0)IU day(-1) , respectively]. 25(OH)D serum levels were insufficient in 51.5% and deficient in 9.7% of the individuals [72.5 (22.3) nmol L(-1) ]. There was a significant positive correlation between dairy product intake with both calcium and vitamin D (r=0.597 and r =0.561, respectively; P=0.000). Adolescents who ate breakfast had a significant higher mean calcium, vitamin D and dairy product intake than adolescents who did not report this meal. CONCLUSIONS The majority of adolescents and young adults did not consume recommended intakes of calcium and vitamin D and also presented 25(OH)D insufficiency. The results indicate that a regular breakfast and the consumption of dairy products represent important strategies in improving calcium and vitamin D intake in the diet.

Do patients with osteogenesis imperfecta need individualized nutritional support

OBJECTIVE Information regarding nutrition and body composition in patients diagnosed with osteogenesis imperfecta (OI) is scarce. In the present study, nutritional status, bone mineral density, and biochemical parameters of subjects with OI were evaluated. METHODS Patients with type I OI (n = 13) and type III OI (n = 13) and healthy controls (n = 8) were selected. Nutritional status and bone mineral density were assessed by a 3-d food diary and dual-energy X-ray absorptiometry at the lumbar spine, respectively. Body mass index, serum albumin, calcium, creatinine, cross-linked C-telopeptide, parathyroid hormone, and 25-hydroxivitamin D(3) were also evaluated. RESULTS Patients with OI had lower bone mineral density (P < 0.05 versus controls). Patients with type III OI had the highest body mass index (P < 0.05 versus patients with type I OI and controls) and the lowest lean body mass (P < 0.05 versus patients with type I OI and controls). In patients with OI, the number of fractures was positively correlated with body mass index (r = 0.581, P = 0.002) and the percentage of body fat (r = 0.451, P = 0.027) and negatively correlated to lean body mass (r = -0.523, P = 0.009). Even when taking dietary supplements, 58% and 12% of subjects with OI did not achieve the calcium and vitamin D recommendations, respectively. CONCLUSIONS Body composition is a risk factor for bone fractures in subjects with OI. Individualized nutritional support is recommended not only to improve body composition but also to potentiate pharmacologic and physical therapies.

Folato, B6 e B12 na adolescência: níveis séricos, prevalência de inadequação de ingestão e alimentos contribuintes

OBJECTIVE: To investigate serum concentrations and the prevalence of inadequate folate intake and also vitamin B6 and vitamin B12 intakes and to identify those foods that make a major contribution to intake levels of these nutrients. METHODS: This was a cross-sectional, observational study of adolescents of both sexes aged 16 to 19 years from the town of Indaiatuba, SP, Brazil. Data collection was by non-consecutive 3-day dietary record. The samples’ habitual diet was estimated by removing intraindividual variability, and the prevalence rates of inadequate intakes were calculated using the estimated average requirement as cutoff points. Biochemical assays for folate, vitamin B6 and vitamin B12 were conducted in accordance with the methods accepted in the literature. RESULTS: The study sample comprised 99 adolescents, the majority of whom were female (58.6%), with a mean age of 17.6 [standard deviation, (SD) 0.9]. Mean serum concentrations for folate, vitamin B6 and vitamin B12 were 9.2 (SD 3.4) ng/mL, 18.7 (SD 5.1) nmol/L and 397.5 (SD 188.4) pg/mL, respectively; and the prevalence rates of inadequate intake for these vitamins were 15.2, 10.2 and < 1%, respectively. The foods that made a major contribution to vitamin intakes were French bread, pasta and beans for folate; white rice, chicken and beef for vitamin B6; and lean beef, whole milk and fatty beef for vitamin B12. CONCLUSIONS: The prevalence rates of inadequate folate, vitamin B6 and vitamin B12 intakes were low, which is possibly the result of improved access to and availability of foods that are dietary sources of these vitamins. Beans, which are a part of the traditional Brazilian diet, remain one of the primary food items that contribute to folate intake, even after mandatory fortification with folic acid in Brazil.

Dietary patterns and bone mineral density in Brazilian postmenopausal women with osteoporosis: a cross-sectional study

Background/Objectives:The aim of this study was to investigate the association between dietary patterns and bone mineral density (BMD) in postmenopausal women with osteoporosis.Subjects/Methods:This cross-sectional study included 156 postmenopausal and osteoporotic Brazilian women aged over 45 years. BMD of lumbar spine, total femur (TF), femoral neck and of total body (TB), as well as body composition (fat and lean mass), was assessed by dual-energy X-ray absorptiometry. Body mass index and lifestyle information were also obtained. Dietary intake was assessed by using a 3-day food diary. Dietary patterns were obtained by principal component factor analysis. Adjusted multiple linear regression analysis was applied in order to evaluate the predictive effect of dietary patterns on BMD. Significance was set at P<0.05.Results:Five patterns were retained: ‘healthy’, ‘red meat and refined cereals’, ‘low-fat dairy’, ‘sweet foods, coffee and tea’ and ‘Western’. The ‘sweet foods, coffee and tea’ pattern was inversely associated with TF BMD (β=−0.178; 95% CI: −0.039 to −0.000) and with TB BMD (β=−0.320; 95% CI: −0.059 to −0.017) even after adjusting for energy and calcium intake, lean mass, age and postmenopausal time.Conclusions:A concomitant excessive consumption of sweet foods and caffeinated beverages appears to exert a negative effect on BMD even when the skeleton already presents some demineralization. Food and beverage intake is a modifiable factor that should not be neglected in the treatment of individuals with osteoporosis.

Body composition changes in haemodialysis patients with secondary hyperparathyroidism after parathyroidectomy measured by conventional and vector bioimpedance analysis.

Considering the negative effects of secondary hyperparathyroidism (SHPT) in patients with chronic renal failure (CRF), the objective of the present study was to evaluate body composition changes using conventional and vector bioimpedance analysis in patients before and after parathyroidectomy (PTX). Twelve adult patients, mean age 43.4 (sd 12.7) years, were evaluated prior to and 6 months after PTX. Diets were assessed with 3 d dietary records, and mean energy, protein, calcium and phosphorus intake were estimated from these inventories. Weight, height, BMI and bioelectrical impedance were measured; and biochemical markers of nutritional status (albumin and total protein) and bone metabolism (calcium, phosphorus and intact parathyroid hormone) were determined. No significant differences were observed in mean energy, protein and phosphorus after surgery. There was a significant increase in calcium intake after PTX (382.3 (sd 209.6) mg to 656.6 (sd 313.8) mg; P<0.05). Mean weight, BMI, conventional bioelectrical impedance measurements, total body fat, lean body mass and total body water were unaffected by surgery. However, the phase angle and reactance significantly increased after PTX (5.0 degrees (sd 1.4) to 5.6 degrees (sd 1.3); 44.1 (sd 15.6) Omega to 57.1 (sd 14.4) Omega, respectively). The high levels of intact parathyroid hormone before surgery had a negative effect on total body fat (r -0.69, P<0.05). After PTX, the mean albumin significantly increased (3.9 (sd 0.4) g/dl to 4.2 (sd 0.6) g/dl; P<0.05). PTX for SHPT is associated with certain changes in laboratory values, dietary intake and body composition. The latter is best seen with bioimpedance vector analysis.

Influência do hiperparatireoidismo secundário grave no estado nutricional de pacientes com insuficiência renal crônica

OBJECTIVE: To evaluate parathyroid hormone effects in the nutritional status of hemodialysis patients with secondary hyperparathyroidism. METHODS: Twenty-six adult patients with a mean age of 47 ± 8 years were evaluated. The patients were divided into two groups according to their levels of parathyroid hormone and matched for gender. Patients in group 1 (n=13) presented parathyroid hormone levels above 300pg/ml (1486 ± 920pg/ml) and patients in group 2 (n=13) below 300pg/ml (199.8 ± 122.2pg/ml). The following parameters were also assessed: 3-day food diaries, anthropometric data and biochemical markers of bone metabolism. RESULTS: Group 1 presented significantly lower body mass index, midarm muscle circumference, skinfold thickness and body fat compared with patients from group 2 (p<0.05). There was a negative and significant correlation between parathyroid hormone and total body fat (r=-0.6; p<0.05). In addition, in the multiple regression analysis, the parathyroid hormone and the time in hemodialysis explain in 42% the decrease in total body fat. Concerning nutrient intakes and biochemical markers, except for parathyroid hormone, there was no statistically significant difference between the two groups. All patients presented lower energy, protein and calcium intakes than those recommended for dialysis patients. Phosphorus intake was 11±.6 and 15±5mg/kg/day for groups 1 and 2, respectively, values considered adequate for this population. CONCLUSION: In conclusion, elevated levels of parathyroid hormone and time in hemodialysis have a negative effect on total body fat and can influence the nutritional status of chronic renal failure patients.

There are no association between vitamin D metabolites and blood pressure in adolescents.

OBJECTIVES The purpose of this study was to evaluate the relationships between serum levels of vitamin D and blood pressure (BP) in adolescents. METHODS The anthropometric measurements, body composition, dietary intake, blood pressure and biochemical measurements was undertaken. RESULTS Two hundred and five adolescents, 106 boys and 99 girls, mean aged 18.2 years old, participate of the study. Elevated BP was observed in 12.19% of the adolescents. Mean 25OHD concentration was 29.2(0.8) ng/mL. Vitamin D insufficiency was observed in 62% of adolescents. There were no correlation between systolic and diastolic BP with 25OHD and 1,25(OH)2D concentration. An inverse correlation between adiponectin and diastolic BP was observed and positive significant correlation was observed between waist circumference with systolic and diastolic BP in both boys and in girls. In conclusion, no relationships between vitamin D levels and blood pressure were observed. CONCLUSION However, the intra-abdominal adiposity offers potential risk to BP elevation in adolescents.

Digital vertebral morphometry performed by DXA: a valuable opportunity for identifying fractures during bone mass assessment.

OBJECTIVES To evaluate the usefulness of vertebral morphometry in identifying unreferred vertebral fractures and correlate potential risk factors. SUBJECTS AND METHODS Female patients above 45 years, postmenopausal for at least 2 years, diagnosed with osteoporosis and undergoing treatment for at least three months were considered eligible. All of them underwent bone densitometry and vertebral morphometry performed by concomitant DXA. The presence of fractures was defined between T7 and L4; only moderate and severe fractures were considered for analysis. All volunteers were submitted to laboratory tests, anthropometry and responded a questionnaire on their lifestyle habits and medical history. RESULTS Thirty two (17%) out of the 188 female patients presented with at least one vertebral fracture, among whom only 4 (12.5%) were previously aware of the fracture. The fractures were mainly located on the thoracic spine. Nine patients had severe fractures (28.1%), whereas 23 had moderate fractures (71.9%). On average, patients with fractures were 5 years older and weighed 5 kilograms less than those without fractures. The creatinine clearance was on average 9 mL/min less in patients with vertebral fracture. The assessment of vertebral fractures by morphometry is a fast, accurate and complementary method associated with low radiation exposure for identifying moderate and severe vertebral fractures. Predisposition to vertebral fractures does not depend solely on BMD.