The skeletal benefits of calcium- and vitamin D3-fortified milk are sustained in older men after withdrawal of supplementation: an 18 mo follow-up study

Background: In a previous 2-y randomized controlled trial, we showed that calcium- and vitamin D₃–fortified milk stopped or slowed bone loss at several clinically relevant skeletal sites in older men.

Objective: The present study aimed to determine whether the skeletal benefits of the fortified milk were sustained after withdrawal of the supplementation.

Design: One hundred nine men >50 y old who had completed a 2-y fortified milk trial were followed for an additional 18 mo, during which no fortified milk was provided. Bone mineral density (BMD) of the total hip, femoral neck, lumbar spine, and forearm was measured by using dual-energy X-ray absorptiometry.

Results: Comparison of the mean changes from baseline between the groups (adjusted for baseline age, BMD, total calcium intake, and change in weight) showed that the net beneficial effects of fortified milk on femoral neck and ultradistal radius BMD at the end of the intervention (1.8% and 1.5%, respectively; P < 0.01 for both) were sustained at 18-mo follow-up (P < 0.05 for both). The nonsignificant between-group differences at the total hip (0.8%; P = 0.17) also persisted at follow-up (0.7%; P = 0.10), but there were no lasting benefits at the lumbar spine. The average total dietary calcium intake in the milk supplementation group at follow-up approximated recommended amounts for Australian men >50 y old (1000 mg/d) but did not differ significantly from that in the control subjects (1021 versus 890 mg/d).

Conclusion: Supplementation with calcium- and vitamin D₃–fortified milk for 2 y may provide some sustained benefits for BMD in older men after withdrawal of supplementation.

Effect of vitamin D supplementation on vitamin D status and bone turnover markers in young adults

Objective: To assess the vitamin D status of healthy young people living in Northern Ireland and the effect of vitamin D supplementation on vitamin D status and bone turnover.

Design: Double-blinded randomised controlled intervention study.

Setting: University of Ulster, Coleraine, Northern Ireland.

Subjects: In total, 30 apparently healthy students (15 male and 15 female subjects), aged 18–27 years, were recruited from the university, with 27 completing the intervention.

Interventions: Subjects were randomly assigned, to receive either 15 mug (600 IU) vitamin D3 and 1500 mg calcium/day (vitamin D group), or 1500 mg calcium/day (control group) for 8 weeks between January and March. Vitamin D status, bone turnover markers, serum calcium and parathyroid hormone concentrations were measured at baseline and post intervention.

Results: At baseline, vitamin D status was low in both the vitamin D group (47.9 (s.d. 16.0)) and the control group (55.5 (s.d. 18.6) nmol/l 25(OH)D). Post intervention vitamin D status was significantly higher in the vitamin D-treated group (86.5 (s.d. 24.5)) compared to the control group (48.3 (s.d. 16.8) nmol/l) (P<0.0001). There was no significant effect of supplementation on bone turnover markers or PTH concentrations.

Conclusions: This study suggests that young adults in Northern Ireland do not consume an adequate daily dietary intake of vitamin D to maintain plasma vitamin D concentrations in the wintertime. A daily supplement of 15 mug vitamin D3 significantly increased vitamin D status in these individuals to levels of sufficiency. Achievement of an optimum vitamin D status among young adults may have future positive health implications.

Vitamin D: status, supplementation and immuno-modulation

Numerous studies have shown suboptimal vitamin D status in populations at high geographical latitudes, owing to a reduced capacity to synthesise vitamin D, especially during wintertime. Vitamin D supplementation has been shown to be effective at maintaining adequate vitamin D status throughout the year in these countries. Classically reported to play a central role in bone health, vitamin D has more recently been shown to modulate immune function by promoting an anti-inflammatory response, which may be related to onset or progression of autoimmune inflammatory disorders. One such condition is multiple sclerosis (MS). There is an increasing incidence of MS with increasing latitude, with higher prevalence reported in countries further away from the equator, where vitamin D synthesis is inadequate. Vitamin D has been shown to have positive effects on the animal model of MS, experimental autoimmune encephalomyelitis. However, there have been few human intervention studies to investigate the effect of vitamin D supplementation on symptoms of MS or indeed of other autoimmune disorders. Further research is required to examine the potential beneficial role of vitamin D in MS to ultimately determine the optimal vitamin D status required to alleviate symptoms and possibly prevent this and other chronic diseases.

Effect of zinc supplementation on the immune status of healthy older individuals aged 55–70 years : the ZENITH Study

Aging is associated with alterations in the immune system, effects which may be exacerbated by inadequate zinc (Zn) status. We examined the relationship between Zn status and markers of immunity and the effect of supplementation with 15 mg or 30 mg Zn/d for 6 months on immune status in healthy individuals. Zn status was assessed by dietary intake and biochemical indices. Immune status was assessed by multiple flow cytometric methods. At baseline, Zn concentration was positively associated with lymphocyte subpopulation counts and T-lymphocyte activation. Zn supplementation of 30 mg/d significantly lowered B-lymphocyte count, albeit at month 3 only. Lower doses of Zn (15 mg Zn/d) significantly increased the ratio of CD4 to CD8 T lymphocytes at month 6. Overall, these findings suggest that total Zn intake (diet plus supplementation) of up to 40 mg Zn/d do not have significant long-term effects on immune status in apparently healthy persons aged 55–70 years.

Bioequivalence of encapsulated and microencapsulated fish-oil supplementation

Omega-3 oil from fish can be stabilised against oxidation using a variety of microencapsulation technologies. Complex coacervation has been used and found to be commercially useful for fortifying foods and beverages with long-chain omega-3 containing oils. Here we report a comparative human bioavailability study of microencapsulated omega-3 fish oil and standard fish-oil soft-gel capsules. Phospholipid levels of long-chain omega-3 fatty acids increased equivalently in both subjects groups. Also, triacylglycerol levels were reduced similarly in both groups. These results indicate that omega-3 fatty acids have equivalent bioavailability when delivered as microencapsulated complex coacervates or as soft-gel capsules.

α-Linolenic acid supplementation and conversion to n-3 long-chain polyunsaturated fatty acids in humans

Blood levels of polyunsaturated fatty acids (PUFA) are considered biomarkers of status. Alpha-linolenic acid, ALA, the plant omega-3, is the dietary precursor for the long-chain omega-3 PUFA eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA). Studies in normal healthy adults consuming western diets, which are rich in linoleic acid (LA), show that supplemental ALA raises EPA and DPA status in the blood and in breast milk. However, ALA or EPA dietary supplements have little effect on blood or breast milk DHA levels, whereas consumption of preformed DHA is effective in raising blood DHA levels. Addition of ALA to the diets of formula-fed infants does raise DHA, but no level of ALA tested raises DHA to levels achievable with preformed DHA at intakes similar to typical human milk DHA supply. The DHA status of infants and adults consuming preformed DHA in their diets is, on average, greater than that of people who do not consume DHA. With no other changes in diet, improvement of blood DHA status can be achieved with dietary supplements of preformed DHA, but not with supplementation of ALA, EPA, or other precursors.

Multivitamin supplementation improves nutritional status and bone quality in aged care residents

Objectives: To assess the effectiveness of a multivitamin (MV) tablet on nutritional status, quantitative heel ultrasound (QUS), mobility, muscle strength and falls. The design comprised two groups matched on mobility levels, randomized to receive a daily MV or placebo (P) tablet for 6 months. The setting was an Australian residential care facility.

Subjects: A total of 92 aged care residents. Serum micronutrients, body weight, QUS, rate of falls, hand grip strength, and the timed up and go test were assessed at baseline and 6 months.

Results: A total of 49 participants consumed a MV and 43, a matched P for 6 months. There was a greater increase in the MV vs P group for serum 25(OH)D (mean differencestandard error, 33.42.6 nmol l-1), folate (13.42.8 nmol l-1), and vitamin B12 (178.040.3 pmol l-1) (all P<0.001). Adequate 25(OH)D concentrations (50 nmol l-1) were found among 77% of participants in the MV group vs 10% taking P (P<0.001). Adjusting for baseline levels, the increase in QUS was greater in the MV vs P group (3.02.0 dB MHz-1 vs -2.92.1 dB MHz-1, respectively, P=0.041). There was a trend towards a 63% lower mean number of falls in the MV vs P group (0.30.1 falls vs 0.80.3 falls, P=0.078).

Conclusions: MV supplementation raised serum vitamin B12 and folate concentrations and increased serum 25(OH)D, which was accompanied by an apparent positive effect on bone density. We also found a trend towards a reduction in falls and this could contribute to a reduction in fractures.

Histological assessment of intermediate - and long-term creatine monohydrate supplementation in mice and rats

Creatine monohydrate (CrM) supplementation appears to be relatively safe based on data from short-term and intermediate-term human studies and results from several therapeutic trials. The purpose of the current study was to characterize pathological changes after intermediate-term and long-term CrM supplementation in mice [healthy control and SOD1 (G93A) transgenic] and rats (prednisolone and nonprednisolone treated). Histological assessment (18-20 organs/tissues) was performed on G93A mice after 159 days, and in Sprague-Dawley rats after 365 days, of CrM supplementation (2% wt/wt) compared with control feed. Liver histology was also evaluated in CD-1 mice after 300 days of low-dose CrM supplementation (0.025 and 0.05 g · kg^-1 · day^-1) and in Sprague-Dawley rats after 52 days of CrM supplementation (2% wt/wt) with and without prednisolone. Areas of hepatitis were observed in the livers of the CrM-supplemented G93A mice (P < 0.05), with no significant inflammatory lesions in any of the other 18-20 tissues/organs that were evaluated. The CD-1 mice also showed significant hepatic inflammatory lesions (P < 0.05), yet there was no negative effect of CrM on liver histology in the Sprague-Dawley rats after intermediate-term or long-term supplementation nor was inflammation seen in any other tissues/organs (P = not significant). Dietary CrM supplementation can induce inflammatory changes in the liver of mice, but not rats. The observed inflammatory changes in the murine liver must be considered in the evaluation of hepatic metabolism in CrM-supplemented mice. Species differences must be considered in the evaluation of toxicological and physiological studies.

Photodarkening of amorphous selenium under high pressure

The photodarkening phenomena of amorphous Se have been studied by the optical absorption coefficient, sound velocity and attenuation measurements. The light illumination at low temperatures induces the photodarkening, and the photodarkened state is completely recovered by annealing near 306 K corresponding to the glass transition temperature. The photodarkening is enhanced by application of pressure. The sound velocity decreases and the sound attenuation increases by the illumination at low temperature. These suggest that a structural disorder increases in the photodarkened state. Three stages are observed for the recovery process of the photodarkened specimen. The photodarkening and the recovery process are discussed on the basis of VAP (valence alternative pair) model.

Gender-specific inhibition of platelet aggregation following omega-3 fatty acid supplementation

Background and Aims : Increased platelet aggregation is a major risk factor for heart attacks, stroke and thrombosis. Long chain omega-3 polyunsaturated fatty acids (LCn-3PUFA; eicosapentaenoic acid, EPA; docosahexaenoic acid, DHA) reduce platelet aggregation; however studies in the published literature involving EPA and/or DHA supplementation have yielded equivocal results. Recent in vitro studies have demonstrated that inhibition of platelet aggregation by LCn-3PUFA is gender specific. We examined the acute effects of dietary supplementation with EPA or DHA rich oils on platelet aggregation in healthy male and females.

Methods and Results : A blinded placebo controlled trial involving 15 male and 15 female subjects. Platelet aggregation was measured at 0, 2, 5 and 24 h post-supplementation with a single dose of either a placebo or EPA or DHA rich oil capsules. The relationship between LCn-3PUFA and platelet activity at each time point was examined according to gender vs. treatment. EPA was significantly the most effective in reducing platelet aggregation in males at 2, 5 and 24 h post-supplementation (−11%, −10.6%, −20.5% respectively) whereas DHA was not effective relative to placebo. In contrast, in females, DHA significantly reduced platelet aggregation at 24 h (−13.7%) while EPA was not effective. An inverse relationship between testosterone levels and platelet aggregation following EPA supplementation was observed.

Conclusion : Interactions between sex hormones and omega-3 fatty acids exist to differentially reduce platelet aggregation. For healthy individuals, males may benefit more from EPA supplementation while females are more responsive to DHA.