Calcium-vitamin D-fortified milk is as effective on circulating bone biomarkers as fortified juice and supplement but has less acceptance: a randomised controlled school-based trial.

BACKGROUND: Hypovitaminosis D, especially during cold seasons, is quite prevalent among primary school children in Tehran. The present study aimed to compare the efficacy of calcium-vitamin D-fortified-milk, -orange juice and supplement in primary school children. METHODS: Children aged 9-12 years from both sexes were randomly assigned to one of six groups to receive plain milk, fortified milk, plain orange juice, fortified orange juice, supplement or placebo. Both fortified-milk and -juice contained 100 IU of vitamin D and 500 mg of calcium per 200 mL package, whereas supplement contained 200 IU of vitamin D and 500 mg of calcium. The duration of intervention was 12 weeks, from November 2008 to March 2009. RESULTS: A total of 410 children completed the study. Regression analysis with adjustment for both sex and initial values of 25(OH)D revealed that consumption of either supplement, fortified orange juice or fortified milk resulted in a 20.8 nm [confidence interval (CI) = 17.4-23.9], 9.9 nm (CI = 7.4-12.3) or 6.9 nm (CI = 3.3-10.5) increase in circulating 25(OH)D compared to the related control groups. However, changes in serum osteocalcin and intact parathyroid hormone in the supplement group did not differ from those of fortified milk or plain milk. The increment of osteocalcin in both plain milk and fortified milk was more than in fortified orange juice, although the difference was statistically insignificant. CONCLUSIONS: Despite having double amount of vitamin D and being more effective in raising serum 25(OH)D, supplementation did not confer additional benefit in terms of osteocalcin and intact parathyroid hormone compared to either fortified or plain milk.

Daily intake of vitamin D- or calcium-vitamin D-fortified Persian yogurt drink (doogh) attenuates diabetes-induced oxidative stress: evidence for antioxidative properties of vitamin D.

BACKGROUND: Both poor vitamin D status and oxidative stress (OS) have been independently associated with late diabetic complications, including cardiovascular disease (CVD). The present study aimed to examine the effect of daily intake of vitamin D alone or in combination with calcium as a fortified Persian yogurt drink (doogh) on OS over 12 weeks. METHODS: Ninety patients with type 2 diabetes aged 30-50 years from both sexes were randomly allocated to one of the three groups to receive two 250-mL bottles of doogh a day, which was either plain (PD; containing 150 mg per 250 mL of calcium and no detectable vitamin D), vitamin D-fortified (DD; containing 150 mg of calcium + 500 IU vitamin D per 250 mL) or calcium-vitamin D-fortified (CDD; 250 mg od calcium + 500 IU vitamin D per 250 mL). RESULTS: Although mean (SD) serum concentrations of protein carbonyl significantly decreased in both DD and CDD groups [-2.07 (4.39) nm, P = 0.015 and -4.4 (7.64) nm, P = 0.003, respectively], the change in PD group was not significant [-0.54 (6.96) nm, P = 0.674]. A similar pattern was observed for cardiac myeloperoxidase [PD: -19.4 (75.9) µg L(-1) , P = 0.173; DD: -21.8 (54.2) µg L(-1) , P = 0.035, CDD: -48.5 (76.9) µg L(-1) , P = 0.002]. Superoxide dismutase increased significantly only in DD and CDD [56.9 (74.0) U L(-1) , P < 0.001 and 51.6 (119.9) U L(-1) , P = 0.025, respectively]. Changes of serum advanced glycation end-products showed a significant between-group difference among PD, DD and CDD [239.4 (388.4) U L(-1) , -58.1 (147.6) U L(-1) and -143.7 (475.9) U L(-1)  × 10(3) , respectively, P = 0.003], which remained significant after controlling for changes of fasting serum glucose (P = 0.013) and glycated haemoglobin (P = 0.015). CONCLUSIONS: The findings of the present study demonstrated an OS attenuating effect of vitamin D. However, extra calcium did not convey additional benefit.

Evidence for augmented oxidative stress in the subjects with type 1 diabetes and their siblings: a possible preventive role for antioxidants.

BACKGROUND/OBJECTIVES: Oxidative stress (OS) is thought to be involved in both development of type 1 diabetes (T1D) and its further complications. In this study, certain biomarkers of OS were compared among the subjects with T1D, their non-diabetic siblings and unrelated healthy controls. SUBJECTS/METHODS: Known cases of T1D from both sexes aged 5-25 years were enrolled in a case-control study (n(1)=60). There were two control groups; non-diabetic siblings (n(2)=60) and unrelated apparently healthy subjects (n(3)=60). Anthropometric, dietary and laboratory assessments were done. RESULTS: There was no significant difference in dietary data among the groups. Total antioxidant capacity was significantly lower in T1D than both related and unrelated controls (1.6 ± 0.05, 1.7 ± 0.05 and 1.8 ± 0.06 mmol BSA equivalent/l, respectively, P=0.044). Both T1D subjects and their siblings showed lower glutathione peroxidase (GSH-px) levels (median (interquartile range): 22.2 (28.6), 29.9 (23) and 41.8 (73.6) U/ml, respectively, P=0.006). On the contrary, superoxide dismutase concentrations were significantly higher in T1D group and the siblings than unrelated healthy controls (243 (45.3), 157.8 (176.9) and 27.9 (8.7) U/l, respectively, P<0.001). Serum concentrations of GSH correlated with energy intake in the siblings (r=0.521, P<0.001) and unrelated controls (r=0.268, P=0.042) but not in T1D group. The associations remained significant after controlling for blood glucose (r=0.437, P=0.001 and r=0.420, P=0.011, respectively) in both the groups. CONCLUSION: Augmented OS in the siblings may indicate an increased requirement for antioxidants in genetically diabetes-prone subjects.

Vitamin D status and the predictors of circulating T helper 1-type immunoglobulin levels in Iranian subjects with type 1 diabetes and their siblings: a case-control study.

BACKGROUND: Vitamin D status has been linked to both T helper (Th)1/Th2 balance and susceptibility to type 1 diabetes (T1D). The present study aimed to evaluate vitamin D status and its relation to Th1/Th2 balance in subjects with T1D, their siblings and unrelated healthy controls during autumn and winter 2008-2009. METHODS: A case-control study was conducted on subjects with T1D (n(1) = 60) and two control groups comprising nondiabetic siblings (n(2) = 60) and unrelated healthy controls (n(3) = 60). Assessments of dietary intake, anthropometry, intact parathyroid hormone (iPTH) and 25(OH)D were performed. Serum levels of immunoglobulin (Ig)G(2) and IgE, as well as the IgG2/IgE ratio, were used to evaluate Th1/Th2 balance. Vitamin D status was defined based on circulating 25(OH)D as deficiency: <27.5 nm; insufficiency 27.5 ≤ 25(OH)D <50 nm; and sufficiency ≥50 nm. RESULTS: Vitamin D status did not differ significantly among the groups. Similarly, no significant difference in 25(OH)D, iPTH, IgG(2), IgE and IgG(2)/IgE was found. In multiple regression analysis of pooled data, PTH and body mass index were the predictors of IgG(2)/IgE. In the diabetic group, both PTH and age and, in siblings, PTH only, were the predictors of IgG(2)/IgE ratio. CONCLUSIONS: These data suggest PTH as the major predictor of immune deviance towards the Th1 response in both type 1 diabetic subjects and their siblings. Considering that the active form of vitamin D suppresses PTH production, it is hypothesised that vitamin D replenishment of just those who are genetically prone to the disease (i.e. siblings) may be regarded as a preventive measure against T1D.

Physiological dose of lycopene suppressed oxidative stress and enhanced serum levels of immunoglobulin M in patients with Type 2 diabetes mellitus: a possible role in the prevention of long-term complications.

OBJECTIVE: This study was undertaken to evaluate the antioxidant effects of lycopene in physiological doses and its possible effects on the immune response in patients with Type 2 diabetes mellitus (T2DM). RESEARCH DESIGN AND METHODS: A total of 35 patients with T2DM of both sexes aged 54+/-9 yr were enrolled in a double-blind placebo-controlled clinical trial conducted for 2 months. After a 2-week lycopene-free diet washout period, patients were allocated to either lycopene supplementation group (10 mg/day) (no.=16) or placebo group (no.=19), which were age- and sex matched. Patients were instructed to keep their diet and physical activity as unchanged as possible. RESULTS: While dietary intake of energy and body weight did not change, the ratio of serum total antioxidant capacity (TAC) to malondialdehyde (MDA) increased significantly in the lycopene group compared to the placebo group (p=0.007). Though a statistically significant increase in serum concentrations of lycopene (p<0.001) was not accompanied by enhanced delayed-type hypersensitivity response, a significant negative correlation was found between serum levels of lycopene and immunoglobulin (Ig)G (r=-0.338, p=0.008). Interestingly, variations of serum levels of lycopene directly correlated with those of IgM (r=0.466, p=0.005). There was an insignificant decrement in serum anti-oxidized LDL IgG levels in the lycopene group. CONCLUSIONS: Lycopene, probably by increasing TAC and inhibiting MDA-LDL formation, may attenuate T cell-dependent adaptive (pro-atherogenic) immune response. Meanwhile, with enhancement of innate immunity and hence prevention of ox-LDL uptake by macrophage and foam cell formation, lycopene may be effective in prevention of long-term diabetic complications, notably cardiovascular disease.