Micronutrient Status of Recreational Runners with Vegetarian or Non-Vegetarian Dietary Patterns.

Vegetarian diets have gained popularity in sports. However, few data exist on the status of micronutrients and related biomarkers for vegetarian and vegan athletes. The aim of this cross-sectional study was to compare the micronutrient status of omnivorous (OMN, n = 27), lacto-ovo-vegetarian (LOV, n = 26), and vegan (VEG, n = 28) recreational runners. Biomarkers of vitamin B12, folate, vitamin D, and iron were assessed. Additionally, serum levels of calcium, magnesium, and zinc were examined. Lifestyle factors and supplement intake were recorded via questionnaires. About 80% of each group showed vitamin B12 adequacy with higher levels in supplement users. Mean red blood cell folate exceeded the reference range (>340 nmol/L) in all three groups (OMN: 2213 ± 444, LOV: 2236 ± 596, and VEG: 2354 ± 639 nmol/L; not significant, n.s.). Furthermore, vitamin D levels were comparable (OMN: 90.6 ± 32.1, LOV: 76.8 ± 33.7, and VEG: 86.2 ± 39.5 nmol/L; n.s.), and we found low prevalence (<20%) of vitamin D inadequacy in all three groups. Less than 30% of each group had depleted iron stores, however, iron deficiency anemia was not found in any subject. Our findings suggest that a well-planned, health-conscious lacto-ovo-vegetarian and vegan diet, including supplements, can meet the athlete's requirements of vitamin B12, vitamin D and iron.

Alternative Ernährungsformen: Allgemeine Aspekte und vegetarische Kostformen.

Alternative diets (AD) differ from the current common mixed diet; AD are recommended as a permanent diet. These diets are based on ethical, philosophical and health promoting principles and lead to very different recommendations for food selection. Even within a particular AD there is usually a broad spectrum of versions, so that a general evaluation is only possible to a limited extent. This is also true for single AD. Vegetarian diets and partly paleo-diets have been investigated to a reasonable extent. Plant based diets are appropriate as permanent diets and offer health benefits as compared with currently practiced diets (risk reduction of cancers by 10-18% and of heart diseases by 30%; favorable effect on blood pressure and lipid profile; no risk reduction on cancer and total mortality). Vegan diets have to be critically assessed: they are linked to an increased risk of deficits for single nutrients (vitamin B12, iodine and as the case may be. calcium and long chain omega-3 fatty acids), if suitable supplements or fortified foods are not consumed.

[Nutrition and bone health: What ist the evidence?]. / Ernährung und Knochengesundheit.

Nutrients are of particular importance for bone health: they act as structural elements of bones, modulate the activity of osteoblasts and osteoclasts, and influence bone remodeling through various mediators. A bone protective diet can be characterised as a diet rich in fruits and vegetables, dairy products, seeds and nuts, whole grain and soy products and moderate amounts of fish, eggs and lean meat. This diet provides sufficient amounts of protein, calcium, magnesium and vitamins (e. g. K, C, folic acid, B6 and B12), which are important for bone development. For specific nutrients, the following bone-protective recommendations can be given: 1.0-1.3 g protein/kg body weight and day; 1000-1200 mg/day calcium, preferably as part of the normal diet. In case of insufficient calcium intake or on antiresorptive medication a supplementation of 200-500 mg or 500-1000 mg calcium/day, respectively, should be given. Furthermore, for prevention of bone fractures a cut off level of ≥ 75 nmol calcidiol/l is suggested.

[The calcium debate--strong bones at the expense of cardiovascular health?]. / Calcium: Knochenschutz auf Kosten der Gefässe?

Ensuring an adequate intake of calcium--by means of supplements, if necessary--is a well-established approach in prevention and therapy of osteoporosis. However, in the meantime concerns have been voiced doubting the safety of calcium supplements. The discussion commenced when a new evaluation of the Auckland calcium intervention study revealed a higher rate of myocardial infarction after administration of calcium, compared to placebo. Two meta-analyses on the cardiovascular risk of calcium supplements supported these findings. Nevertheless, these results are still discussed contentiously. Doubts were increased by the fact that neither a reevaluation of the WHI calcium vitamin D study, nor a current meta-analysis could identify calcium as a cardiovascular risk factor. Against this background the present article analyses the controversial data with respect to the well-known "Hill-criteria" of causality, including consistency of data, magnitude of association, dose-response relationship and biological plausibility.

Breastfeeding woman are at higher risk of vitamin D deficiency than non-breastfeeding women - insights from the German VitaMinFemin study.

BACKGROUND: Despite increased awareness of the adverse health effects of vitamin D deficiency, only a few studies have evaluated the vitamin D status (25-hydroxyvitamin D [25(OHD)]) of breastfeeding women and up to now, no information exits for German breastfeeding women. Therefore, the aim of study was to determine the vitamin D status of breastfeeding women compared to non-pregnant and non-breastfeeding (NPNB) women. METHODS: This cross-sectional study investigated 124 breastfeeding women and 124 age and season matched NPNB women from the German "Vitamin and mineral status among German women" study. The study participants were recruited from April 2013 to March 2015 and did not take vitamin D supplements. Serum 25(OH)D was analyzed by chemiluminescent immunoassay. RESULTS: Vitamin D deficiency (<25.0 nmol/L) was prevalent in 26.6% of the breastfeeding women. The majority of women (49.2%) showed 25(OH)D concentration between 25.0 and 49.9 nmol/L. In multiple binary logistic regression analysis, breastfeeding women had a 4.0-fold higher odds ratio (OR) (95% confidence interval [CI] 1.8, 8.7) for vitamin D deficiency than NPNB women. For breastfeeding women, the risk of vitamin D deficiency was higher in the winter and spring months (OR: 2.6, 95% CI 1.1, 6.3) and increased with lower longitude per one unit (OR 0.7, 95% CI 0.6, 0.9). CONCLUSION: Breastfeeding women in Germany had a higher risk of deficient vitamin D levels than NPNB women. In further studies, the optimal vitamin D status for breastfeeding women should be investigated and also the required vitamin D doses to ensure this vitamin D status. TRIAL REGISTRATION: German Clinical Trial Register (identification number: DRKS00004789).

L-Arginine and vascular health. / Bedeutung von L-Arginin für die Gefäßgesundheit.

Endothelial dysfunction, characterized by a disturbed vascular NO metabolism, represents a key point in atherogenesis. Modern antiatherogenic therapies improve NO availability within the endothelium. As L-arginine acts as the substrate of endothelial nitric oxide synthase (eNOS), arginine supplementation can enhance NO formation. Actually, L-arginine at appropriate dosage (6­8 g/day) improves endothelial function and lowers blood pressure. However, beneficial effects can only be expected in individuals with pronounced endothelial dysfunction and/or individuals with an absolute (patients with hemodialysis) or relative (patients with elevated ADMA levels) arginine deficiency. Whether L-arginine delays progression of atherosclerotic lesions and lowers cardiovascular morbidity and mortality is unknown.

Folate and Prevention of Neural Tube Defects: New Insights from a Bayesian Model.

Maternal folate status before and during pregnancy influences a woman's risk of having a pregnancy affected by congenital malformations of the neural tube (neural tube defects, NTD). For NTD prevention, it is recommended that women use periconceptional supplementation of folic acid. However, the recommended dose varies considerably (400 - 800 µg folic acid/day). Insufficient data exists on the relation between folate status and the risk of NTD. A recent study published in the British Medical Journal provides evidence for a generalizable dose-response relation between folate status and risk of NTD. The lowest risk of having a child with NTD was related to red blood cell (RBC) folate concentrations of ≥ 1000 nmol/L.

[Safety of folic acid]. / Sicherheit von Folsäure. Fakten und Fiktionen.

Improving dietary folate intake is a central public health goal. However, critical voices have become louder warning of too high intake of folic acid. Safety concerns of a high folic acid exposure are usually limited to synthetic folic acid contained in drugs and food supplements. Against this background, the present article focuses on two matters: (a) How do the absorption and metabolism of synthetic folic acid differ from that of other folates? (b) How has the longterm safety of folic acid to be judged, especially regarding the risk of colorectal cancer, autism, asthma, impaired immune defence, masking vitamin B12 deficiency and interactions with the methotrexate metabolism?

[Food supplements--possibilities and limitations: Part 6, Safety and possible risks]. / Nährstoffsupplemente--Möglichkeiten und Grenzen. Teil 6: Sicherheit und mögliche Risiken.

Due to the precautionary principle in consumer protection, thresholds for long-term safety of nutrients have to be defined. Three toxical indicators are of interest: lowest observed adverse effect level (LOAEL); no observed adverse effect level (NOAEL) und tolerable level of upper intake (UL). An uptake of a nutrient within the range of UL is without side effects even on the basis of long-term consumption. The UL can be used to derive maximum levels for nutrients in food supplements. In general, vitamins can be regarded as safe nutrients except for vitamin A. Adverse effects only occur at excessive intake far beyond the recommended daily allowances. In contrast, the range of safe intake for minerals, especially trace elements, is much smaller. This can be seen clearly in the case of selenium. In order to prevent severe selenium deficiency a plasma concentration of > 0.25 micromol/l (> 20 microg/l) must be reached. To minimize cancer risk a plasma concentration of 1.5 micromol/l (120 microg/l) is needed. First signs of selenium intoxications occur at plasma levels over 250 microg/l. It is the dose that makes the preventive effect and the poison as well.

[Food supplements in primary prevention--methodological aspects]. / Nährstoffsupplemente--Möglichkeiten und Grenzen. Teil 5: Supplemente in der Primärprävention--Methodologische Aspekte.

The terms "evidence" or "evidence-based medicine" (EBM) dominate the current biomedical debate. When asked about the usefulness of nutritional supplements, increasingly reliable studies and "evidence-based" recommendations are demanded. However, usually, it remains unclear what is meant by "evidence" and "evidence-based medicine". The aim of the current paper is to clarify and explain why continuous designed evaluation instruments, proofing the efficacy of pharmacological active compounds, cannot be applied without modifications to prove the benefits of nutrients. The focus bases on the following questions: (a) What does evidence-based medicine exactly means and how does it differ from non-evidence-based medicine? (b) What is the meaning of "evidence" and "evidence-based statements"? (c) What types of studies are suitable for securing evidence? (d) How can be drawn summarizing conclusions from various, sometimes divergent, results of single studies? (e) Which specific characteristics must be considered in the nutrition context?

[Celiac disease--the chameleon among the food intolerances]. / Zöliakie. Das Chamäleon unter den Nahrungsmittelintoleranzen.

Celiac disease is an autoimmune disorder resulting from gluten intolerance and is based on a genetically predisposition. Symptoms occur upon exposure to prolamin from wheat, rye, barley and related grain. The pathogenesis of celiac disease has not yet been sufficiently elucidated but is being considered as an autoimmune process. At its core are the deamidation of prolamin fragments, the building of specific antibodies and the activation of cytotoxic T-cells. The immunological inflammatory process is accompanied by structural damages of the enterocytes (villous atrophy, colonization and crypt hyperplasia). The symptoms and their extent depend on the type of the celiac disease; classic and non-classic forms are being distinguished (atypical, oligosymptomatic, latent and silent celiac disease). Characteristics of the classic presentation are malabsorption syndrome and intestinal symptoms such as mushy diarrhea and abdominal distension. The diagnosis of celiac disease is based on four pillars: Anamnesis and clinical presentation, serological evidence of coeliac specific antibodies (IgA-t-TG; IgA-EmA), small intestine biopsy and improvement of symptoms after institution of a gluten-free diet. The basis of the therapy is a lifelong gluten-free diet, i. e. wheat, rye, barley, spelt, green-core, faro-wheat, kamuth and conventional oats as well as food items obtained therefrom. Small amounts of up to 50 mg gluten per day are usually tolerated by most patients; amounts of > or = 100 mg/day lead mostly to symptoms. Gluten-free foods contain < or = 20 ppm or 20 mg/kg (Sign: symbol of the 'crossed ear' or label 'gluten-free'). At the beginning of the therapy the fat and lactose intake may need to be reduced; also the supplementation of single micronutrients (fat-soluble vitamins, folic acid, B12, iron, and calcium) may be required. Alternative therapies are being developed but have not yet been clinically tested.

[Food supplements--potential and limits: part 3]. / Nährstoffsupplemente--Möglichkeiten und Grenzen. Teil 3: Supplemente im höheren Lebensalter.

Ageing processes are associated with physiological changes, e.g. a reduction of metabolically active body mass and an impaired hunger-satiety regulation, which--combined with chronic diseases and psychosocial problems--significantly increase the risk for malnutrition. However, considering their nutrition and health status elderly people are a very heterogeneous group. The nutrition situation of "young" seniors does generally not differ from the situation of working-age adults while institutionalized elderly people and those in need of care often show signs of a global malnutrition. The critical nutrients in the nutrition of the elderly particularly include vitamin B12 and D. Six percent of all elderly have a manifest and 10 to 30% a functional vitamin B12 deficiency. The main cause is vitamin B12 malabsorption resulting from a type B atrophic gastritis. The functional vitamin B12 deficiency and the associated hyperhomocysteinemia are risk factors for neurodegenerative diseases and accelerate bone loss. With increasing age the vitamin D status is deteriorating. About 50% of the elderly living in private households is deficient in vitamin D; in geriatrics vitamin D deficiency is more the rule than an exception. This is caused by a reduced endogenous biosynthesis, low UVB exposure and a diet low in vitamin D. A vitamin D deficiency increases the risk for falls and fractures as well as the risk for neurodegenerative diseases. Also the overall mortality is increased.

[Nutrient supplements--possibilities and limitations: part 2]. / Nährstoffsupplemente--Möglichkeiten und Grenzen Teil 2: Ausgewählte Risikogruppen--Supplemente in der Schwangerschaft.

Pregnant women are at greater risk of an insufficient vitamin and mineral supply. Based on hemodynamic, endocrine and metabolic changes due to pregnancy, the body weight and blood volume increase. These changes result in an increased requirement of most vitamins and minerals while the energy requirement increases by about 10%. Besides iodine (recommended intake as supplement 150 microg/d), iron (recommended intake 30-40 mg/d), vitamin D (recommended intake as supplement 20-50 microg/d), and docosahexaenoic acid (recommended intake 200 mg/d), folic acid is one of the critical micronutrients during pregnancy. Food folate and synthetic folic acid differ in their bioavailability. About 50% of the food folate is absorbed whereas almost 100% of folic acid from supplements is bioavailable. The contents are thus indicated as folate equivalents. In the form ofTHF, folic acid functions as coenzyme for the transfer of C1 units in the metabolism of amino acids, purines and pyrimidines. Folic acid (isolated or in combination with other vitamins and minerals) reduces the total risk for neural tube defects by 72%. For primary prevention it is recommended that all women who are planning to become pregnant take 400-800 microg synthetic folic acid along with a diet rich in folate. The additional intake should be continued at least until the end of the first trimester. For secondary prevention of neural tube defects an intake of 4 mg/d is recommended.

[Nutrient supplements - possibilities and limitations]. / Nährstoffsupplemente - Möglichkeiten und Grenzen. Teil 1: Von den rechtlichen Rahmenbedingungen zur Ergä nzungsfunktion.

The consumption of micronutrient-supplements by the general public has become widespread; between 25 and more than 40% of individuals questioned in western developed nations confirm to regularly consume such products. In principle, there are two product categories for micronutrient-supplements - medicinal products (drugs) and foodstuffs. The latter are marketed as food supplements (FS) and dietary foodstuffs for particular nutritional uses including foods for special medical purposes (FSMP). FS serve the general supplementation of any consumer whilst foodstuffs for particular nutritional uses are directed at consumers with special dietary requirements; FSMP are intended for the dietary management of patients. There are clearly defined legal frameworks for those product categories. Independently of their legal product status, six areas of application can be characterised for micronutrient-supplements: general and special supplementation, primary prevention, compensation of disease-related deficits, therapeutic function and containment of diseases or avoidance of subsequent damages (secondary and tertiary function). Gauged with the mean-intake, micro nutrient supply in Germany is sufficient (exception: folic acid and vitamin D; partially also iodine). However, the intake of vitamins E, C, B1 and B2 as well as the minerals calcium, magnesium, zinc and iodine could be improved in 20-50% of the general public. Micro nutrient preparations in physiological dose could contribute to closing this gap in supply.

[Food supplements--potential and limits. Part 4: supplements in primary prevention--conceptual aspects]. / Nährstoffsupplemente--Möglichkeiten und Grenzen. Teil 4: Supplemente in der Primärprävention--Konzeptionelle Aspekte.

Consumer's main cause for the use of food supplements is "disease prevention", but the benefit in prevention remains controversial. Furthermore, there are differing opinions concerning the doses of nutrients that should be applied. The conflict is due to two different sights of view on the effect of nutrients to health. The "classical" approach is on an endpoint: A deficit of a particular nutrient is associated with a specific deficiency syndrome. This means that the lack of a nutrient leads via a defined mechanism to one specific disease-related endpoint. Thus the adequate intake of nutrients is defined as the one in which no specific deficiency symptoms occur. In contrast, the modem approach is based on a multidimensional understanding of the nutrient-endpoint-relationship, taking into account long-term health effects. According to this extended approach, the adequate amount of nutrients is the one in which no specific, short-term deficiencies occur as well as the risk of chronic diseases is generally minimized. Usually, required nutrient intake to reach this exceeds the minimum requirements by several times.

Micronutrients at the interface between inflammation and infection--ascorbic acid and calciferol. Part 2: calciferol and the significance of nutrient supplements.

As explained in the first part of the article, vitamins and trace elements influence various metabolic functions that are directly related to immune function. In this context, secosteroid vitamin D has met with growing interest. The discussion has focused on whether and, if so, to what extent, vitamin D might contribute to the prevention and possibly the treatment of infections and autoimmune diseases. We know, for instance, that immune cells are capable of synthesizing calcitriol from its precursor calcidiol, whereby the former enhances the synthesis of antibacterial peptides by macrophages while simultaneously inhibiting the (auto)immune response mediated by T helper cells (Th1). Numerous observational studies support the hypothesis that a vitamin D deficit increases the risk of autoimmune diseases such as type 1 diabetes mellitus, multiple sclerosis, psoriasis and rheumatoid arthritis; however, there are few reliable interventional studies to date. In general, immune status represents a sensitive indicator of micronutrient supply. Conversely, the activity of the immune system has an effect on the status of and requirements for nutrients.

Micronutrients at the interface between inflammation and infection--ascorbic acid and calciferol: part 1, general overview with a focus on ascorbic acid.

As elements of the antioxidant system, cofactors of enzymes, components of transcription factors, and epigenetic modulators, micronutrients, such as vitamins and trace elements, influence various metabolic processes that are directly associated with immune functions. Specifically, the vitamins C and D have been shown to have significance immune function. Therefore, the objective of this review is to elucidate interactions between micronutrients and the immune system. In the initial section of this review, we present a general overview of interactions between the immune system and micronutrients, with a focus on the immunobiologically relevant functions of vitamin C. Immune competent cells accumulate vitamin C against a concentration gradient, with a close relationship between vitamin C supply and immune cell activity, especially phagocytosis activity and T-cell function. Accordingly, one of the consequences of vitamin C deficiency is impaired resistance to various pathogens, while an enhanced supply increases antibody activity and infection resistance.

Nutrition in oncology: the case of micronutrients (review).

In the course of cancer disease, many oncological patients develop tumor-associated malnutrition characterized by an insufficient supply of macro- and micronutrients. The inadequate nutritional status and the cancer anorexia-cachexia syndrome related to it are clinically relevant, as the response to antineoplastic measures, such as radiation and chemotherapy, is diminished, their side effects aggravated and the patient's quality of life and prognosis negatively affected. Therefore, the supportive nutrition care of oncological patients is of central importance. In this context, vitamins, minerals and long-chain omega -3 fatty acids are becoming more and more relevant in oncology although the benefit of such supplements is discussed controversially. Starting from a description of the etiopathogenesis and the pathophysiological consequences of cancer-associated malnutrition, the present study provides an overview of the importance of micronutrients for oncological patients. In the case of reduced food intake and/or inappropriate food choice the use of a multi-vitamin-multimineral supplement administered in physiological doses, i.e. nutrient quantities approximately corresponding to the recommended daily allowances, can be generally recommended. However, to enhance postoperative wound healing, it seems that cancer patients require higher amounts of micronutrients than healthy individuals. Because vitamin D deficiency is highly prevalent in oncological patients, improvement of vitamin D status is of special interest.

[Vitamin C and immune function]. / Vitamin C und Immunfunktion.

The immune system is strongly influenced by the intake of nutrients. For a long time there has been a controversy whether vitamin C can contribute to the prevention and therapy of the common cold. Several cells of the immune system can indeed accumulate vitamin C and need the vitamin to perform their task, especially phagocytes and t-cells. Thus a vitamin C deficiency results in a reduced resistance against certain pathogens whilst a higher supply enhances several immune system parameters. With regard to the common cold different studies including meta-analyses underline that the prophylactic intake of vitamin C may slightly reduce the duration of the illness in healthy persons but does not affect its incidence and severity. Supplementation of vitamin C is most effective in cases of physical strain or insufficient intake of the vitamin. With regard to the therapy of the common cold the application of vitamin C alone is without clinical effects.