Variation of 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2 levels in human plasma obtained from 758 Japanese healthy subjects

Plasma levels of 25-hydroxyvitamin D3 (25-OH-D3) and 25-hydroxyvitamin D2 (25-OH-D2) in 758 Japanese healthy subjects (most of them adults) were determined by a high-performance liquid chromatographic method previously reported (6) and the following results were obtained: The mean and standard deviation (M +/- SD) of the assayed values of 25-OH-D (sum of 25-OH-D3 and 25-OH-D2) was 23.8 +/- 10.1 ng/ml. 25-OH-D3 was detected in all the samples and the M +/- SD was 23.0 +/- 10.1 ng/ml. The plasma levels clearly showed the seasonal variation that the levels in summer were significantly higher than those in winter. Moreover, the plasma levels were significantly correlated with the amounts of UV light in solar radiation. These results strongly suggested that 25-OH-D3 in plasma mainly originated from endogenous vitamin D3 formed by photo-conversion of 7-dehydrocholesterol in skin. 25-OH-D2 was detected only in 18.3% of the plasma samples and the M +/- SD in the detected samples was 4.4 +/- 2.9 ng/ml which was much lower than those of 25-OH-D3. The results suggested that few healthy Japanese are taking daily exogenous vitamin D2 from multivitamin preparations or others. The M +/- SD values of 25-OH-D3 plasma levels in men and women were 26.2 +/- 10.4 and 19.3 +/- 8.0 ng/ml, respectively. The formers were significantly higher than the latters. The results were thought to be due to the reason that men might be outdoors for longer periods than women. When age variation of plasma 25-OH-D3 levels was examined, the levels in the twenties were significantly lower than the other generations. This was confirmed to be due to the low values observed in the female twenties group, but the detailed reason is unclear at the present time. When 4 healthy volunteers were orally administered 400 I.U./day of vitamin D2 every day for 8 weeks, maximum levels (average: 11.5 ng/ml) were observed at the 8 weeks and the levels gradually decreased after stopping the administration. The results suggested that the half life of 25-OH-D2 in plasma might be 4-5 weeks.     

Effect of consumption of chicory inulin on bowel function in healthy subjects with constipation: a randomized,double-blind,placebo-controlled trial

Constipation is among the most common health impairments in Western countries. This study aimed to determine the effect of the chicory-derived fermentable dietary fiber Orafti^® Inulin on stool frequency in healthy subjects with constipation. The study was conducted according to recent guidance documents for investigating bowel function and used a randomized, double-blind, placebo-controlled, cross-over design with a 2-week wash-out phase. Each study period comprised a run-in phase followed by 4 weeks daily intake of 3?×?4g inulin or maltodextrin (placebo). Forty-four healthy volunteers with constipation documented stool frequency and consistency, gastrointestinal characteristics and quality of life. Consumption of Orafti^® Inulin significantly increased stool frequency compared to placebo (median 4.0 [IQR 2.5–4.5] versus 3.0 [IQR 2.5–4.0] stools/week, p?=?0.038). This was accompanied by a softening of stools and trend toward higher satisfaction versus placebo (p?=?0.059). In conclusion, Orafti^® Inulin was effective in volunteers with chronic constipation and significantly improved bowel function.

Clinical trial registration: This trial was registered at clinicaltrials.gov as NCT02548247.     

Prevalence and significance of low 25-hydroxyvitamin D concentrations in healthy subjects in Delhi

BACKGROUND: Despite abundant sunlight, rickets and osteomalacia are prevalent in South Asian countries. The cause of this paradox is not clear. OBJECTIVE: The objective was to assess 25-hydroxyvitamin D [25(OH)D] status and its functional significance in apparently healthy subjects residing in Delhi, a city in the northern part of India. DESIGN: Serum 25(OH)D, total calcium, inorganic phosphate, alkaline phosphatase, intact parathyroid hormone, and 1, 25-dihydroxyvitamin D [1,25(OH)(2)D] were measured in groups of healthy subjects who differed with respect to variables relevant to vitamin D and bone mineral metabolic status, such as direct sunlight exposure, season of measurement, skin pigmentation, dietary calcium and phytate contents, and altered physiologic states such as pregnancy and neonatal age. RESULTS: All groups except one with maximum direct sunlight exposure had subnormal concentrations of 25(OH)D. The 25(OH)D-deficient groups tended to have an imbalance in bone mineral metabolic homeostasis when exposed to winter weather and low dietary calcium and high dietary phytate, with significantly low calcium and elevated intact parathyroid hormone concentrations, chemical osteomalacia, or both. Increased values of 1,25(OH)(2)D during pregnancy did not help correct the imbalance in bone mineral metabolic homeostasis. CONCLUSION: Healthy subjects with low 25(OH)D concentrations are at risk of bone mineral metabolic imbalance when exposed to factors that strain bone mineral homeostasis.     

Administration of a dietary supplement ( N-oleyl-phosphatidylethanolamine and epigallocatechin-3-gallate formula) enhances compliance with diet in healthy overweight subjects: a randomized controlled trial

Many studies have found that N-oleyl-ethanolamine (NOE), a metabolite of N-oleyl-phosphatidylethanolamine (NOPE), and epigallocatechin-3-gallate (EGCG) inhibit food intake. The main aim of this study was to evaluate the efficacy of 2 months of administration of an oily NOPE-EGCG complex (85 mg NOPE and 50 mg EGCG per capsule) and its effect on compliance with diet in healthy, overweight people. Secondary end-points of the study were to compare body composition, metabolic parameters, sensation of appetite, depressive symptoms and severity of binge eating. Using a parallel-arm, double-blind, placebo-controlled design, 138 healthy, overweight women (106) and men (thirty-two) were randomly assigned to one of two groups: (1) the treatment group (seventy-one patients: fifty-three females, eighteen males) taking two capsules per day of an oral supplement or (2) the placebo group (sixty-seven patients: fifty-three females, fourteen males). Both groups observed a 3344 kJ/d energy restriction. All parameters were assessed both before onset and after 2 months on the supplement. Dropout was 6 % in the NOPE-EGCG group and 27 % in the placebo group (P < 0.001). The treatment induced a significant weight reduction in both groups ( - 3.28 kg and - 2.67 kg in NOPE-EGCG and placebo, respectively); the weight changes were not significantly different between the groups. NOPE-EGCG treatment improved insulin resistance (P < 0.001), the sensation feelings of fullness (P < 0.05), depressive symptoms (P < 0.004) and severity of binge eating (P < 0.0001).     

Enhancement of a modified Mediterranean-style, low glycemic load diet with specific phytochemicals improves cardiometabolic risk factors in subjects with metabolic syndrome and hypercholesterolemia in a randomized trial

Background

As the worldwide dietary pattern becomes more westernized, the metabolic syndrome is reaching epidemic proportions. Lifestyle modifications including diet and exercise are recommended as first-line intervention for treating metabolic syndrome. Previously, we reported that a modified Mediterranean-style, low glycemic load diet with soy protein and phytosterols had a more favorable impact than the American Heart Association Step 1 diet on cardiovascular disease (CVD) risk factors. Subsequently, we screened for phytochemicals with a history of safe use that were capable of increasing insulin sensitivity through modulation of protein kinases, and identified hops rho iso-alpha acid and acacia proanthocyanidins. The objective of this study was to investigate whether enhancement of a modified Mediterranean-style, low glycemic load diet (MED) with specific phytochemicals (soy protein, phytosterols, rho iso-alpha acids and proanthocyanidins; PED) could improve cardiometabolic risk factors in subjects with metabolic syndrome and hypercholesterolemia.

Methods

Forty-nine subjects with metabolic syndrome and hypercholesterolemia, aged 25–80, entered a randomized, 2-arm, 12-week intervention trial; 23 randomized to the MED arm; 26 to the PED arm. Forty-four subjects completed at least 8 weeks [MED (n = 19); PED (n = 25)]. All subjects were instructed to follow the same aerobic exercise program. Three-day diet diaries and 7-day exercise diaries were assessed at each visit. Fasting blood samples were collected at baseline, 8 and 12 weeks for analysis.

Results

Both arms experienced equal weight loss (MED: -5.7 kg; PED: -5.9 kg). However, at 12 weeks, the PED arm experienced greater reductions (P < 0.05) in cholesterol, non-HDL cholesterol, triglycerides (TG), cholesterol/HDL and TG/HDL compared with the MED arm. Only the PED arm experienced increased HDL (P < 0.05) and decreased TG/HDL (P < 0.01), and continued reduction in apo B/apo A-I from 8 to 12 weeks. Furthermore, 43% of PED subjects vs. only 22% of MED subjects had net resolution of metabolic syndrome. The Framingham 10-year CVD risk score decreased by 5.6% in the PED arm (P < 0.01) and 2.9% in the MED arm (P < 0.05).

Conclusion

These results demonstrate that specific phytochemical supplementation increased the effectiveness of the modified Mediterranean-style low glycemic load dietary program on variables associated with metabolic syndrome and CVD.     

Flaxseed on cardiovascular disease markers in healthy menopausal women: a randomized, double-blind, placebo-controlled trial

OBJECTIVE: Due to its high content of lignans, alpha-linolenic acid and fiber, flaxseed may reduce cardiovascular disease risk in humans. The present study evaluated the effect of flaxseed on markers of cardiovascular disease risk in healthy menopausal women. METHODS: One hundred ninety-nine women were randomly assigned to consume 40 g daily of flaxseed or wheat germ placebo for 12 mo. Fatty acids, apolipoproteins A-1 and B, lipoprotein(a), low-density lipoprotein particle size, fibrinogen, C-reactive protein, insulin, and glucose were measured at baseline and at 12 mo. RESULTS: In total 179 women were available for the intention-to-treat analysis. Flaxseed increased plasma alpha-linolenic (P < 0.0001), docosapentaenoic (P = 0.001), and total omega-3 fatty (P = 0.0004) acids. Differences between flaxseed and wheat germ were observed for apolipoprotein A-1 (-0.10 +/- 0.26 g/L, P = 0.011) and apolipoprotein B (-0.05 +/- 0.16 g/L, P = 0.047). From baseline, flaxseed raised apolipoproteins A-1 and B by 4.4% (P = 0.006) and 3% (P = 0.054), whereas wheat germ increased these apolipoproteins by 11.6% (P < 0.0001) and 7% (P = 0.0001), respectively. Both treatments increased lipoprotein(a) (P < 0.0001) and decreased low-density lipoprotein peak particle size (P < 0.0001). CONCLUSION: In this large, long-term, placebo-controlled trial in healthy menopausal women, flaxseed increased some omega-3 fatty acids in plasma and had a limited effect on apolipoprotein metabolism.     

Effect of fish-oil supplementation on mental well-being in older subjects: a randomized, double-blind, placebo-controlled trial

BACKGROUND: It is suggested that a low intake of fish and/or n-3 PUFA is associated with depressed mood. However, results from epidemiologic studies are mixed, and randomized trials have mainly been performed in depressed patients, yielding conflicting results. OBJECTIVE: We investigated the effect of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on mental well-being in a double-blind, placebo-controlled trial. DESIGN: Independently living individuals (n = 302) aged > or =65 y were randomly assigned to consume 1800 mg/d EPA+DHA, 400 mg/d EPA+DHA, or placebo capsules for 26 wk. Changes in mental well-being were assessed as the primary outcome with the Center for Epidemiologic Studies Depression Scale (CES-D), Montgomery-Asberg Rating Scale (MADRS), Geriatric Depression Scale (GDS-15), and Hospital Anxiety and Depression Scale (HADS-A). RESULTS: Plasma concentrations of EPA+DHA increased by 238% in the high-dose and 51% in the low-dose fish-oil group compared with the placebo group, reflecting excellent compliance. Baseline CES-D scores ranged from 5.9 to 6.8 in the 3 groups and were not significantly different between groups. Mean changes in CES-D scores after 26 wk were -0.2, 0.2, and -0.4 (P = 0.87) in the high-dose fish oil, low-dose fish oil, and placebo groups, respectively. Treatment with neither 1800 mg nor 400 mg EPA+DHA differentially affected any of the measures of mental well-being after 13 or 26 wk of intervention compared with placebo. CONCLUSIONS: In this randomized, double-blind, placebo-controlled trial we observed no effect of EPA+DHA supplementation for 26 wk on mental well-being in the general older population studied. This trial was registered at clinicaltrials.gov as NCT00124852.     

Effects of a high-fiber diet on symptoms of irritable bowel syndrome: a randomized clinical trial

OBJECTIVE: We investigated the effects of dietary fiber on symptoms of irritable bowel syndrome. METHODS: A single-blind randomized clinical trial was designed. Fifty-six subjects with irritable bowel syndrome were prospectively and randomly assigned to one of two groups: group 1 received a diet containing 10.4 g/d of fiber and group 2 received a diet containing 30.5 g/d of fiber. Patients' body weights, nutritional intakes as assessed with 3-d written food records, and symptom scores were assessed at baseline and at 3 mo. RESULTS: There were no dropouts during the study. Total energy intake and the distribution of macronutrients were not significantly different between groups. Total dietary fiber intake did not reach recommended levels in either group but was higher in group 2 than in group 1 (25.95 +/- 2.12 g/d versus 6.06 +/- 2.7 g/d, P < 0.05). Initial fiber intake did not differ significantly between groups. Pain scores, bowel scores, and general scores improved in both groups (from baseline to 3 mo), and no significant differences were detected between groups. CONCLUSIONS: A modest fiber intake in patients with irritable bowel syndrome relieved symptoms, but this therapeutic benefit of fiber may have been due to a placebo effect because the results were similar in the low-fiber group.     

Postprandial lipemia in men with metabolic syndrome,hypertensives and healthy subjects

Background  

The metabolic syndrome (MetS), as well as postprandial hypertriglyceridemia, is associated with coronary heart disease. This study aimed to evaluate the postprandial lipemia after oral fat tolerance test (OFTT) in subjects with MetS and compare them to hypertensive (HTN) and healthy subjects.     

Effect of sun exposure versus oral vitamin D supplementation on serum 25-hydroxyvitamin D concentrations in young adults: A randomized clinical trial

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Tanning is associated with optimal vitamin D status (serum 25-hydroxyvitamin D concentration) and higher bone mineral density

BACKGROUND: Vitamin D is made in the skin on exposure to solar radiation, and it is necessary to optimal skeletal health. Subjects who use a tanning bed that emits ultraviolet B radiation (290-315 nm) are likely to have higher 25-hydroxyvitamin D [25(OH)D] concentrations than do subjects who do not regularly use a tanning bed. OBJECTIVE: The first objective of this study was to ascertain whether subjects who regularly use a tanning bed have higher 25(OH)D concentrations than do subjects who do not use a tanning bed. The second objective was to ascertain whether higher 25(OH)D concentrations correlated positively with bone mineral density. DESIGN: This cross-sectional analysis examined 50 subjects who used a tanning bed at least once a week and 106 control subjects. Each subject gave a blood specimen for measurement of serum 25(OH)D and parathyroid hormone concentrations. Each subject underwent bone mineral density testing of the hip and spine. RESULTS: Subjects who used a tanning bed had serum 25(OH)D concentrations 90% higher than those of control subjects (115.5 +/- 8.0 and 60.3 +/- 3.0 nmol/L, respectively; P <0.001). Subjects who used a tanning bed had parathyroid hormone concentrations 18% lower than those of control subjects (21.4 +/- 1.0 and 25.3 +/- 0.8 pg/mL, respectively; P=0.01). Tanners had significantly higher BMD and z scores at the total hip than did nontanners. CONCLUSION: The regular use of a tanning bed that emits vitamin D-producing ultraviolet radiation is associated with higher 25(OH)D concentrations and thus may have a benefit for the skeleton.     

Effects of vitamin D supplementation on 25-hydroxyvitamin D, high-density lipoprotein cholesterol, and other cardiovascular disease risk markers in subjects with elevated waist circumference

The objective of the present trial was to assess the effects of vitamin D supplementation on serum 25-hydroxyvitamin D [25(OH)D] and high-density lipoprotein cholesterol (HDL-C) in subjects with high waist circumference. Subjects were randomly assigned a daily multivitamin and mineral (MVM) supplement or a MVM supplement plus vitamin D 1,200 IU/day (MVM+D) for 8 weeks. There was a significant difference in mean change for 25(OH)D between the MVM and MVM+D treatment groups ( - 1.2 ± 2.5 nmol/l vs. 11.7 ± 3.0 nmol/l, respectively; P = 0.003). Vitamin D 1,200 IU/day did not increase 25(OH)D to a desirable level ( ≥ 75 nmol/l) in 61% of participants. There were no significant changes in cardiovascular disease risk markers. Thus, vitamin D supplementation with 1,200 IU/day was insufficient to achieve desirable serum 25(OH)D in most participants and did not affect cardiovascular disease risk markers.     

Effects of vitamin D supplementation on 25-hydroxyvitamin D,high-density lipoprotein cholesterol,and other cardiovascular disease risk markers in subjects with elevated waist circumference

The objective of the present trial was to assess the effects of vitamin D supplementation on serum 25-hydroxyvitamin D [25(OH)D] and high-density lipoprotein cholesterol (HDL-C) in subjects with high waist circumference. Subjects were randomly assigned a daily multivitamin and mineral (MVM) supplement or a MVM supplement plus vitamin D 1,200 IU/day (MVM+D) for 8 weeks. There was a significant difference in mean change for 25(OH)D between the MVM and MVM+D treatment groups ( ? 1.2 ± 2.5 nmol/l vs. 11.7 ± 3.0 nmol/l, respectively; P = 0.003). Vitamin D 1,200 IU/day did not increase 25(OH)D to a desirable level ( ≥ 75 nmol/l) in 61% of participants. There were no significant changes in cardiovascular disease risk markers. Thus, vitamin D supplementation with 1,200 IU/day was insufficient to achieve desirable serum 25(OH)D in most participants and did not affect cardiovascular disease risk markers.