424 research outputs found
Vitamin B12: a novel indicator of bone health in vulnerable groups
No full textBackground: A number of modifiable predictors for osteoporosis and fractures have been identified, including nutritional factors, such as vitamin D deficiency and low calcium intake. Cobalamin deficiency has been suggested to affect bone metabolism. Pernicious anaemia, which can result in cobalamin deficiency, has been identified as a risk factor for osteoporosis. Also, it is known that homocystinuria patients are of ten diagnosed with osteoporosis. Both moderate hyperhomocysteinemia and vitamin B12 deficiency are highly prevalent in old age and may play a role in diseases characteristic for old age.Objectives: 1) To show the associations of vitamin B12 and homocysteine with measures of bone health in three different populations. 2) To assess the effect of supplementation with 1000 mg crystalline cobalamin, carried either by a milk product or a capsule, on cobalamin status in mildly cobalamin deficient Dutch elderly people .Results: Data analyses in three different populations supplied the following information. Macrobiotic-fed adolescents: adolescents (9-15 y) with a low BMD had a significantly less favorable vitamin B12 status (adjusted mean, SD: 344 :t 24 pmol/L) and MMA status (adjusted mean, P5, P95: 0.31 [0.26, 0.35] f-lIDol/L) than adolescents with a normal BMD, with levels of respectively 442 (18) and 0.20 (0.16, 0.23) f-lmol/L. Free-living elderly: An increased Hcy level appeared to be a strong and independent risk factor for osteoporotic fractures in elderly men and women of the Longitudinal Aging Study Amsterdam (n=1267, mean age: 76 yrs). Relative risks (95% CI) for the highest Hcy quartile versus lowest three homocysteine quartiles were 4.6 (1.4-14.5) in men, and 1.8 (0.8-3.7) in women. Frail elderly people: Osteoporosis (defined by BMD T-score< -2.5) occurred almost five times more of ten in frail elderly women with a marginal vitamin B12 status and seven times more of ten in women with a deficient vitamin B12 status than in women with a normal status in the VFit-study. Intervention study with vitamin B12: Crystalline cobalamin added to milk is an effective alternative for cobalamin capsules in improving cobalamin status.Conclusions: We found a relevant association between vitamin B12 metabolites and bone health in various studies with different study designs and diverse populations. Since these observed associations broaden the scope for randomized clinical trials, we conducted an intervention study in which we showed that milk enriched with vitamin B12 is an as effective treatment as cobalamin capsules
Seniorenvoeding biedt volop kansen voor midden- en kleinbedrijf
No full textDe komende dertig jaar groeit het aantal vijftigplussers in Nederland met 45 procent naar 7,1 miljoen. De groep zal bijna twee keer zoveel vermogen hebben als het gemiddelde Nederlandse huishouden. Een nieuwe markt met kansen. Ooit dacht de consument bij seniorenvoeding vooral aan de saaie keuken van een bejaardenhuis of een sondevoeding voor oudere patiënten. Tegenwoordig is dat anders. De huidige senioren zijn vaak vitale consumenten, met veel aandacht voor hun kwaliteit van leven, die geld overhebben voor een goede voeding. Senioren blijken een gat in de markt, zo bleek tijdens het symposium dat het Innovatiecentrum Gezonde Voeding (ICGV) deze zomer in Venlo hiel
Vitamin B-12 deficiency stimulates osteoclastogenesis via increased homocysteine and methylmalonic acid
No full textThe risk of nutrient deficiencies increases with age in our modern Western society, and vitamin B(12) deficiency is especially prevalent in the elderly and causes increased homocysteine (Hcy) and methylmalonic acid (MMA) levels. These three factors have been recognized as risk factors for reduced bone mineral density and increased fracture risk, though mechanistic evidence is still lacking. In the present study, we investigated the influence of B(12), Hcy, and MMA on differentiation and activity of bone cells. B(12) deficiency did not affect the onset of osteoblast differentiation, maturation, matrix mineralization, or adipocyte differentiation from human mesenchymal stem cells (hMSCs). B(12) deficiency caused an increase in the secretion of Hcy and MMA into the culture medium by osteoblasts, but Hcy and MMA appeared to have no effect on hMSC osteoblast differentiation. We further studied the effect of B(12), Hcy, and MMA on the formation of multinucleated tartrate-resistant acid phosphatase-positive osteoclasts from mouse bone marrow. We observed that B(12) did not show an effect on osteoclastogenesis. However, Hcy as well as MMA were found to induce osteoclastogenesis in a dose-dependent manner. On the basis of these results, we conclude that B(12) deficiency may lead to decreased bone mass by increased osteoclast formation due to increased MMA and Hcy levels
Prioritizing micronutrients for the purpose of reviewing their requirements:a protocol developed by EURRECA
No full textThe EURRECA (EURopean micronutrient RECommendations Aligned) Network of Excellence (http://www.eurreca.org) is working towards the development of aligned recommendations. A protocol was required to assign resources to those micronutrients for which recommendations are most in need of alignment
Folate Intake and Markers of Folate Status in Women of Reproductive Age, Pregnant and Lactating Women: A Meta-Analysis
No full textBackground. Pregnant and breastfeeding women are at risk for folate deficiency. Folate supplementation has been shown to be associated with enhanced markers of folate status. However, dose-response analyses for adult women are still lacking. Objective. To assess the dose-response relationship between total folate intake (folic acid plus dietary folate) and markers of folate status (plasma/serum folate, red blood cell folate, and plasma homocysteine); to evaluate potential differences between women in childbearing age, pregnant and lactating women. Methods. Electronic literature searches were carried out on three databases until February 2010. The overall pooled regression coefficient (β) and SE(β) were calculated using meta-analysis on a double-log scale.
Results. The majority of data was based on nonpregnant, nonlactating women in childbearingage. The pooled estimate of the relationship between folate intake and serum/plasma folate was 0.56 (95% CI = 0.40–0.72, P<0.00001); that is, the doubling of folate intake increases the folate level in serum/plasma by 47%. For red blood cell folate, the pooled-effect estimate was 0.30 (95% CI = 0.22–0.38, P<0.00001), that is, +23% for doubling intake. For plasma-homocysteine it was –0.10 (95% = –0.17 to –0.04, P=0.001), that is, –7% for doubling the intake. Associations tended to be weaker in pregnant and lactating women. Conclusion. Significant relationships between folate intake and serum/plasma folate, red blood cell folate, and plasma homocysteine were quantified. This dose-response methodology may be applied for setting requirements for women in childbearing age, as well as for pregnant and lactating women
Optimal Operation of a Network of Multi-purpose Reservoir: A Review
No full textAbstractDue to the effects of climate change and population growth, reservoirs play a more and more important role in water resources management. The management of a multi-reservoir system is complex due to the curse of dimensionalities, nonlinearities and conflicts between different objectives. The optimal operation of a multi-reservoir system operation typically involves optimization and simulation models, which can provide the quantitative information to improve operational water management. The objectives of this paper are to extend previous state-of-the-art reviews in the operational management of a network of multi-purpose reservoirs with recent developments and to focus on the application of Model Predictive Control for real time control of a reservoir system
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