Intestinal absorption of vitamin D: a systematic review

Use of carotenoids in feed mixtures for poultry: a review

Carotenoids are present in ingredients of feed for poultry. Their content can be further increased by supplementation of feed mixtures with synthetic or natural carotenoids. The present paper recapitulates knowledge on the use of carotenoids in broiler chickens and laying hens, and deals with synthetic or natural carotenoids derived from plants. The review describes effects of carotenoids on productive performance, oxidative stability of poultry products, colouring of yolks and accumulation of carotenoids in yolks. There are several alternatives to synthetic carotenoids which are usable in poultry diets and satisfy the interest of consumers in poultry products free of undesirable side effects.

Effect of 25-HydroxyVitamin D Deficiency and Its Interaction with Prednisone Treatment on Musculoskeletal Health in Growing Mdx Mice

Duchenne muscular dystrophy (DMD) results from genetic mutations of the gene encoding dystrophin, leading to muscle inflammation and degeneration that is typically treated with glucocorticoids. DMD and its treatment with glucocorticoids result in poor bone health and high risk of fractures. Insufficient levels of 25-hydroxyvitamin D (25-hydroxy D) that may contribute to weakened bone are routinely found in DMD patients. To determine the effect of 25-hydroxy D deficiency, this study examined the effects of low vitamin D dietary intake with and without glucocorticoids on the musculoskeletal system of the Mdx mouse model of DMD. At 10 weeks of age, Mdx mice on control diet had low trabecular bone mineral density of distal femurs and lumbar vertebrae with increased osteoclast numbers compared to wild-type mice. Low vitamin D intake resulted in 25-hydroxy D deficiency but had no effect on trabecular or cortical bone. Cortical bone loss and bone weakness were induced by glucocorticoids while they improved muscle grip strength in Mdx mice. 25-hydroxy D deficiency did not result in any significant effects on growing bone or muscle in the Mdx mice. In combination with glucocorticoid treatment, low 25-hydroxy D resulted in no change in cortical bone mineral density but bone ductility was significantly increased suggesting lower bone mineralization.

Vitamin D fortification of foods and prospective health outcomes

Vitamin D is essential for bone health and has significant roles in non-skeletal health and organ function. Dermal synthesis through exposure to ultraviolet B light is the major natural source of vitamin D, while only a small portion of the necessary amount can be acquired by a diet without fortified foods. In recent years, vitamin D deficiency as a result of lifestyles with inadequate sun exposure, has received increased attention due to its association with the increased risk of serious chronic diseases. This review summarizes our current understanding of food fortification strategies with vitamin D and the resulting health impact. Conventional and biotechnological approaches can be used for the production of new and novel vitamin D rich or vitamin D fortified foods. The availability of a wider range of every-day consumed fortified foods as part of a "Daily D" public health policy can contribute to the improvement of vitamin D status and to prevention of vitamin D deficiency.

Italian Association of Clinical Endocrinologists (AME) and Italian Chapter of the American Association of Clinical Endocrinologists (AACE) Position Statement: Clinical Management of Vitamin D Deficiency in Adults

Vitamin D deficiency is very common and prescriptions of both assay and supplementation are increasing more and more. Health expenditure is exponentially increasing, thus it is timely and appropriate to establish rules. The Italian Association of Clinical Endocrinologists appointed a task force to review literature about vitamin D deficiency in adults. Four topics were identified as worthy for the practicing clinicians. For each topic recommendations based on scientific evidence and clinical practice were issued according to the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) System. (1) What cut-off defines vitamin D deficiency: even though 20 ng/mL (50 nmol/L) can be considered appropriate in the general population, we recommend to maintain levels above 30 ng/mL (75 nmol/L) in categories at risk. (2) Whom, when, and how to perform screening for vitamin D deficiency: categories at risk (patients with bone, liver, kidney diseases, obesity, malabsorption, during pregnancy and lactation, some elderly) but not healthy people should be screened by the 25-hydroxy-vitamin D assay. (3) Whom and how to treat vitamin D deficiency: beyond healthy lifestyle (mostly sun exposure), we recommend oral vitamin D (vitamin D2 or vitamin D3) supplementation in patients treated with bone active drugs and in those with demonstrated deficiency. Dosages, molecules and modalities of administration can be profitably individually tailored. (4) How to monitor the efficacy of treatment with vitamin D: no routine monitoring is suggested during vitamin D treatment due to its large therapeutic index. In particular conditions, 25-hydroxy-vitamin D can be assayed after at least a 6-month treatment. We are confident that this document will help practicing clinicians in their daily clinical practice.