Current Nutrition & Food Science - Volume 10, Issue 1, 2014

Vitamin D, a calciotropic hormone, is gaining attention for many aspects of health, particularly metabolic regulation. As societal trends towards increasing caloric intake become more prominent, the concern for diseases stemming from chronic inflammation grows. Excess caloric intake results in increased lipid and fatty acid storage in adipose tissue leading to adipocyte hypertrophy and hyperplasia. Adipocytes produce cytokines and adipose-related hormones and can promote a systematic chronic proinflammatory state with the development of the metabolic syndrome and increasing risk of cardiovascular disease. Proinflammatory cytokines can signal immunocytes to injure the pancreas and endothelium. This, in turn can result in a reduction in insulin secretion and increasing insulin resistance. Vitamin D may possess therapeutic potential for metabolism associated diseases, as a result of its role in metabolic regulation and its action on adipocytes and myocytes. Vitamin D inhibits adipocyte maturation and differentiation, and reduces the production of proinflammatory cytokines and adipose- related hormones by adipocytes. The purpose of this review is to elucidate the current literature on the therapeutic potential of vitamin D repletion in the treatment and prevention of metabolic and cardiovascular diseases. Although associations exist between vitamin D insufficiency and obesity, diabetes, hyperlipidemia, cardiovascular and all- cause mortality, there have not been prospective trials that have demonstrated the benefit of vitamin D in alleviating manifestations of disease. Nevertheless, correction of vitamin D insufficiency would be expected to confer many health benefits. A greater understanding of the interaction of vitamin D with not only adipose tissue but other components of the human metabolic regulatory system, such as the hypothalamus, pancreas, and bone, may help tailor interventions including vitamin D supplementations that address cardiovascular disease and obesity.

A number of studies have looked at Vitamin D supplementation as a possible means of therapy for atopic dermatitis (AD). The aim of this review was to summarize the current evidence on the role of vitamin D supplementation in the management of AD using the data from published clinical studies. We searched PubMed and Cochrane Central Registry of Trials to look for studies evaluating the effects of vitamin D in AD. Four studies which specifically investigated vitamin D supplementation and its possible role as a management tool in AD were identified; three of these were randomized. The evidence from the studies suggests that vitamin D may be a beneficial tool in the management of AD. However, due to the paucity in the number of studies, small sample sizes and variability in study designs and dosages, it is difficult to definitively conclude at this time whether vitamin D supplementation can be recommended as a management tool in patients with atopic dermatitis. Further observational and randomized studies investigating the effects of vitamin D in AD are warranted.

There is a growing interest in the possible associations between vitamin D and depression. In this mini-review we present diagnostic criteria of different depression scales, with special focus on somatic complaints, possible links between depression and vitamin D and an overview of studies on vitamin D levels / vitamin D supplementation in depressed patients. We observed that complaints of a somatic character, potentially linked to vitamin D deficiency, are important parts of the diagnostic assessment in depression. Depressed patients often had low levels of vitamin D, and seven out of nine large (n>1000) observational studies showed an association between vitamin D levels and depression. Five studies of vitamin D supplementation in depressed patients with vitamin D deficiency showed significant reductions in depressive symptoms post-supplementation. However, only two of these studies were randomized controlled trials, and one of them had only 15 subjects. We recommend that depressed patients should generally be screened for vitamin D deficiency. Aside an increased risk of impaired bone health, individual patients may have symptoms of depression related to potentially deficient vitamin D levels. However, further randomized controlled studies of the effects of vitamin D supplementation in depressed patients are needed.

Background: Obesity often coexists with poor vitamin D status. There is emerging evidence that improving vitamin D status could lower prevalence of many chronic diseases. We questioned whether vitamin D influenced body fat mass. Methods: A literature search from 1995 to date was conducted using prominent databases. Selection criteria included human, randomized controlled trials (RCTs) that were designed to test the supplementation of vitamin D on body weight and composition. Results: Eleven RCTs (4 primary and 7 secondary) that supplemented vitamin D met our criteria. Nine studies were of good quality with a Jadad et al. score ≥3. Three favoured an effect of vitamin D on body fatness, while six showed no difference between treatments. Better vitamin status before or during an RCT predicted greater weight and/or fat loss in a few trials. Conclusion: Current evidence from RCTs of good quality did not unequivocally support the contention that vitamin D accelerated weight or fat loss in obesity. Direct mechanistic pathways for obesity prevention remain untested in humans, though an indirect effect through an improvement in calcium metabolism, was plausible. Outcomes from trials recently completed or in progress will strength the evidence base in this important area.

Quercetin, a widely occurring plant flavonoid, is well-known for its antioxidant activity. A great deal of research in the form of animal and cell culture studies has been performed over the last 30 years, as well as a few clinical studies in human populations; however, its specific effects on various contributing factors to cardiovascular disease are not fully understood. This review seeks to summarize many of the latest studies regarding the effects of quercetin on cardiovascular health. Overall, the research reflects positive effects of quercetin on atherosclerosis, hypertension, dyslipidemia and endothelial function. However, in vivo studies have shown that quercetin imparts varying plasma levels due to its poor aqueous solubility and low stability in biological fluids. Research efforts are currently being devoted to overcome these limitations by designing and testing modified forms of quercetin or improved formulations which provide enhanced bioavailability and higher efficacy. The development of improved dosage forms for in vivo administration of quercetin and well-designed clinical studies are warranted for further evaluation of the effects of quercetin on cardiovascular health.

Selenium (Se)-enriched yeast is a common form of Se for supplementation purpose. In this paper Se retention and metabolism in body, content in natural food and supplements have been introduced. Then recent investigations on the beneficial health effects of Se-enriched yeast addition to foods and impact of process variables in its production as well as, product characteristic, Se species, intended dietary use for Se-enriched yeast, bioavailability and stability have been reviewed. Finally safety of the yeast source in Se-enriched yeast, probable toxicity including acute and chronic toxicity have been discussed. Application of Se-enriched yeast, complying with the general product characteristics outlined in paper when used in food supplements is safe at the proposed intake levels, which upper bound total estimated daily intake for adults was calculated to be 150 µg as Se.

Prickly pear is the fruit of the nopal cactus; native from Mexico, where approximately 80 species and 150 cultivars are harvested. Production of prickly pear has been expanded to more than 30 countries. In Latin America, almost 511,035 Ton per year of prickly pear are harvested, which represents more than 50% of the worldwide production of this fruit. There are studies that have demonstrated its importance as a source of nutritional and functional compounds that provide antioxidant, antiatherogenic, antiulcerogenic, immunomodulatory and anticarcinogenic properties. Prickly pear is commonly consumed fresh, since the pulp is the edible portion; while peel and seeds are discarded as waste, these residuals contain minerals, dietary fiber, phenolics, and flavonoids in higher levels than the pulp, which could be used as a source of functional ingredients. There are findings related to the phytochemical composition of the prickly pear with functional effects, and further clinical studies are still needed in order to determine the mechanisms of action of these compounds, which could provide a greater added value to this fruit in the health area.

The essential oil of caraway (CEO) was analyzed by GC-MS. Its predominant components were (Z)-anethole (26.34%), carvone (17.85%), limonene (15.45%), hydrocinnamyl acetate (8.29%) and carvacrol (6.68%). Antioxidant activity (AOA) of CEO was evaluated in cake during 60 days storage at 25°C. CEO at 0.10 and 0.15% could inhibit the rate of oxidation products formation in cake and their effect was almost equal to BHA at 0.02% (p<0.01). AOA of CEO maybe due to the presence of carvone, limonene and carvacrol. Also, the antimycotic effect of CEO was evaluated in cake during 60 days storage and results indicated that CEO at 0.10 and 0.15% could prevent the growth of fungi in it. Organoleptic evaluation of cakes containing 0.05, 0.10 and 0.15% of CEO showed no significant difference between them and the control sample (p<0.01). This essential oil could be used as natural preservative in foodstuffs especially those containing lipid.

In this research, spray drying was used to produce malt extract powder. The effect of two parameters including inlet air temperature (at levels 160, 170, 180°C) and maltodextrin concentration (at levels 0, 10, 20, 30%) was investigated on malt extract powder properties including particle size, theoretical specific surface area, particle size distribution and span value, scorched particles and solubility index, vitamin B2 content, glass transition and sticky point temperature. Results indicated that spray drying method produced a malt extract powder with high quality. The drying efficiency depended on inlet air temperature and maltodextrin concentration. Increasing inlet air temperature and maltodextrin concentration enhanced the drying performance. The highest quality factors for the powdered malt extract were obtained at 170°C and 20% maltodextrin, which included disk B for scorched particles, solubility amount=0.05 ml, average particle size= 22 microns, vitamin B2 content=1.56mg-100g.