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Despite the role of calcium and vitamin D in osteoporosis and heart disease, little research has examined changes in the intake of calcium and vitamin D among individuals with these conditions over time. Using data from the 2004 and 2015 Canadian Community Health Surveys, we investigated changes in dietary and supplemental intake of calcium and vitamin D among Canadian older adults aged ≥ 50 years, both with and without heart disease and/or osteoporosis, between 2004 and 2015. Notable declines in dietary calcium intake occurred, particularly among non-supplement users. Surprisingly, individuals with osteoporosis and heart disease, who are at higher nutritional risk, were less likely to use calcium supplements in 2015 compared to 2004. Among calcium supplement users, those with osteoporosis or both conditions experienced significant reductions in their usual calcium intake in 2015, with an increased proportion failing to meet recommended intake levels. Conversely, vitamin D supplement users experienced a substantial rise in vitamin D intake in 2015. In 2015, only a small proportion of supplement users did not meet the recommended vitamin D intake levels. These findings underscore the importance of public health initiatives to facilitate safe increases in calcium and vitamin D intake for older adults, particularly those with heart disease and osteoporosis. [ABSTRACT FROM AUTHOR]

There is a need to increase the options for vitamin D fortification. We have developed a method to fortify hard cheese with vitamin D. Our aim was to characterize the bioavailability of vitamin D from fortified cheeses. Eighty adults were randomized to weekly servings of fortified cheddar cheese (DC) (34 g; n = 20); fortified low-fat cheese (DLF) (41 g; n = 10); liquid vitamin D supplement (1 mL), taken with food (DS+) (n = 20) or without food (DS-) (n = 10); placebo cheddar cheese (n = 10); or placebo supplement (n = 10). The treatments contained 28,000 IU cholecalciferol (vitamin D3), equivalent to 4000 IU (100 [micro]g/d). The primary outcome was the comparison of vitamin D bioavailability, as measured by the serum 25-hydroxyvitamin D [25(OH)D] response, between fortified cheeses and supplement. In the placebo groups, initial 25(OH)D, 55.0 [+ or -] 25.3 nmol/L, declined over the 8-wk winter protocol, to 50.7 [+ or -] 24.2 nmol/L (P = 0.046). In the vitamin D-treated groups, the mean increases in 25(OH)D over 8 wk were: 65.3 [+ or -] 24.1 (DC), 69.4 [+ or -] 21.7 (DLF), 59.3 [+ or -] 23.3 (DS+), and 59.3 [+ or -] 19.6 nmol/L (DS-); these changes differed from the placebo groups (P < 0.0001 ) but not from one another (P = 0.62). Compared with baseline, serum parathyroid hormone decreased with both fortification (P = 0.003) and supplementation (P = 0.012). These data demonstrate that vitamin D is equally bioavailable from fortified hard cheeses and supplements, making cheese suitable for vitamin D fortification.

In the USA, vitamin D supplements are sold over-the-counter as tablets, caplets or drops containing varying levels of vitamin D between 10 g and 250 g(17) explaining why a stand-alone vitamin D supplement could be effective in raising 25(OH)D levels above the target 25(OH)D concentration. Preventing vitamin D deficiency during the COVID-19 pandemic: UK definitions of vitamin D sufficiency and recommended supplement dose are set too low. An important gap in our ability to implement an effective approach needed to maintain vitamin D status among older adult residents is the lack of an integrated system of vitamin D supplement use in place across LTC facilities. [Extracted from the article]

Background: Evidence is lacking to determine whether there have been any changes in dietary or total usual intakes of vitamin D among Canadians, in the light of recent evidence of beneficial health effects beyond bone.Objective: We aimed to examine trends in dietary and total usual intake of vitamin D among Canadians aged ≥1 y.Methods: This study used nationally representative nutrition data from the Canadian Community Health Survey Cycle 2.2 (CCHS 2004) and CCHS Nutrition in 2015. Dietary intake data were collected with use of two 24-h dietary recalls and dietary supplement use was determined by questionnaire. The National Cancer Institute method was used to estimate the usual intake of vitamin D as well as the prevalence of vitamin D inadequacy among Canadians aged ≥1 y.Results: From 2004 to 2015, the usual intake of vitamin D from food significantly decreased (P < 0.05) by 1 μg/d only in vitamin D supplement nonusers. The contribution of Milk and Alternatives food group (i.e., fluid milk, fortified soy beverages, powdered milk, and other milk alternatives) to dietary vitamin D intake significantly decreased (P < 0.05) in both supplement users (by 7.1%) and nonusers (by 5.8%). Prevalence of vitamin D supplement use and percentage contribution of vitamin D from supplemental sources significantly increased (P < 0.05) by 5.0% and 14.9%, respectively, from 2004 to 2015. Total usual intake of vitamin D (food + supplement) significantly increased (P < 0.05) from 15.1 ± 0.3 μg/d in 2004 to 31.5 ± 1.8 μg/d in 2015 in vitamin D supplement users. In contrast to vitamin D supplement nonusers, the prevalence of vitamin D inadequacy significantly decreased (P < 0.05) from 20.6% to 14.1% among users of vitamin D supplements.Conclusions: The prevalence of vitamin D supplement use and the percentage contribution of vitamin D from supplemental sources has increased in the Canadian population over an 11-y period. [ABSTRACT FROM AUTHOR]

Vitamin D deficiency can lead to musculoskeletal diseases such as rickets and osteomalacia, but vitamin D supplementation may also prevent extraskeletal diseases such as respiratory tract infections, asthma exacerbations, pregnancy complications and premature deaths. Vitamin D has a unique metabolism as it is mainly obtained through synthesis in the skin under the influence of sunlight (i.e., ultraviolet-B radiation) whereas intake by nutrition traditionally plays a relatively minor role. Dietary guidelines for vitamin D are based on a consensus that serum 25-hydroxyvitamin D (25[OH]D) concentrations are used to assess vitamin D status, with the recommended target concentrations ranging from ≥25 to ≥50 nmol/L (≥10–≥20 ng/mL), corresponding to a daily vitamin D intake of 10 to 20 μg (400–800 international units). Most populations fail to meet these recommended dietary vitamin D requirements. In Europe, 25(OH)D concentrations <30 nmol/L (12 ng/mL) and <50 nmol/L (20 ng/mL) are present in 13.0 and 40.4% of the general population, respectively. This substantial gap between officially recommended dietary reference intakes for vitamin D and the high prevalence of vitamin D deficiency in the general population requires action from health authorities. Promotion of a healthier lifestyle with more outdoor activities and optimal nutrition are definitely warranted but will not erase vitamin D deficiency and must, in the case of sunlight exposure, be well balanced with regard to potential adverse effects such as skin cancer. Intake of vitamin D supplements is limited by relatively poor adherence (in particular in individuals with low-socioeconomic status) and potential for overdosing. Systematic vitamin D food fortification is, however, an effective approach to improve vitamin D status in the general population, and this has already been introduced by countries such as the US, Canada, India, and Finland. Recent advances in our knowledge on the safety of vitamin D treatment, the dose-response relationship of vitamin D intake and 25(OH)D levels, as well as data on the effectiveness of vitamin D fortification in countries such as Finland provide a solid basis to introduce and modify vitamin D food fortification in order to improve public health with this likewise cost-effective approach. [ABSTRACT FROM AUTHOR]

Background: Despite varying serum levels of 25(OH)D among schoolchildren in Ethiopia, data are lacking whether this affects their muscle function as measured by handgrip strength of these children. Handgrip strength may be used as a proxy indicator of muscle strength and function. This study evaluated the association between serum levels of 25(OH)D and handgrip strength among schoolchildren in Ethiopia.Methods: The study used a data set from a school-based cross-sectional study conducted on a total of 174 randomly selected schoolchildren from urban (N = 89) and rural (N = 85) settings of Adama Town and Adama Woreda, respectively. Handgrip strength, serum 25(OH)D levels, and anthropometry were measured for each child following standard procedures, while data on demographic characteristics of children and their parents were collected using a structured interviewer-administered questionnaire. A multivariable linear regression model was used to determine the association between serum vitamin D level and handgrip strength after adjusting for other predictors.Results: The mean handgrip muscle strength of the students was 17.6 ± 6.9 kg. The average serum 25(OH)D for the group was 54.5 ± 15.8 nmol/L. On multivariable linear regression model, serum 25(OH)D level was significantly associated with handgrip strength (β = 0.06, P = .008) of the children after controlling for potential confounders. Other variables, female gender (β = -2.20, P = .004), age (β = 1.97, P < .001), height (β = .22, P < .001), weight (β = 0.33, P < .001), and triceps skinfold thickness (β = -0.19, P = .023), were identified to have significant association with handgrip strength of schoolchildren.Conclusion: Serum 25(OH)D levels had significant positive association with handgrip strength of Ethiopian schoolchildren. The results imply the need for incorporating school nutrition education on consumption of foods rich in important nutrients including vitamin D-rich foods in the school curricula and also enhancing behavioral change communication toward exposure to sunlight in the school to produce adequate vitamin D. Further longitudinal study involving a larger sample is recommended to confirm the findings. [ABSTRACT FROM AUTHOR]

Introduction: There is evidence that 25-hydroxyvitamin D levels are lower in overweight and obese youth. This study examined the relationship between weight status and 25-hydroxyvitamin D, while controlling for confounders, in Canadian youth. Methods: Plasma 25-hydroxyvitamin D from subjects aged 6 to 17 years from the Canadian Health Measures Survey cycles 1 (2007 to 2009) and 2 (2009 to 2011) was used. Sex-specific multiple linear regression and logistic regressions examined the relationship of overweight and obesity (body mass index = 85th percentile) with 25-hydroxyvitamin D levels and the odds of 25-hydroxyvitamin D <40 nmol/L and <50 nmol/L. Results: The prevalence of risk of vitamin D deficiency (25-hydroxyvitamin D < 30 nmol/L) was 6% (95% confidence interval [CI] 3.26% to 10.12%). Vitamin D inadequacy, estimated by levels <40 nmol/L, was 15% (95% CI 10.34% to 20.39%; 19% [95% CI 13.1 to 25.6] for teenagers). Seventy per cent (95% CI 63.59 to 75.17) had levels >50 nmol/L, consistent with achieving the Recommended Dietary Allowance. In adjusted analyses, overweight/obesity (1/3 of subjects) was independently associated with lower 25-hydroxyvitamin D for both sexes after adjustment for age, race, income, season, vitamin D supplementation and daily milk consumption. For 25-hydroxyvitamin D <40 nmol/L, the overweight/obese odds ratio for males was 2.63 (95% CI 1.34 to 5.18). For 25-hydroxyvitamin D <50 nmol/L, overweight/obese odds ratios were 2.19 (95% CI 1.46 to 3.28) for males and 1.39 (95% CI 1.05 to 1.84) for females. Conclusions: This study confirms the inverse association between adiposity and serum concentrations of 25-hydroxyvitamin D in Canadian youth and the independent association of overweight/obesity to 25-hydroxyvitamin D level and vitamin D status after adjustment for other factors. [ABSTRACT FROM AUTHOR]

We determined the association between vitamin D status as 25hydroxyvitamin D [25(OH)D] and disease activity in a cohort of 201 Crohn's Disease (CD) patients in Saskatoon, Canada over three years. The association between high-sensitivity C-reactive protein (hs-CRP) and 25(OH)D and several disease predictors were evaluated by the generalized estimating equation (GEE) over three time-point measurements. A GEE binary logistic regression test was used to evaluate the association between vitamin D status and the Harvey-Bradshaw Index (HBI). The deficient vitamin D group (≤29 nmol/L) had significantly higher mean hs-CRP levels compared with the three other categories of vitamin D status (p < 0.05). CRP was significantly lower in all of the other groups compared with the vitamin D-deficient group, which had Coef. = 12.8 units lower (95% CI -19.8, -5.8), Coef. 7.85 units (95% CI -14.9, -0.7), Coef. 9.87 units (95% CI -17.6, -2.0) for the vitamin D insufficient, adequate, and optimal groups, respectively. The vitamin D status was associated with the HBI active disease category. However, the difference in the odds ratio compared with the reference category of deficient vitamin D category was only significant in the insufficient category (odds ratio = 3.45, p = 0.03, 95% CI 1.0, 10.8). Vitamin D status was inversely associated with indicators of disease activity in Crohn's disease, particularly with the objective measures of inflammation. [ABSTRACT FROM AUTHOR]

Background: Vitamin D supplementation is recommended for breastfed infants. Maternal supplementation beginning in gestation is a potential alternative, but its efficacy in maintaining infant 25-hydroxyvitamin D [25(OH)D] concentration after birth is unknown. Objectives: We determined the effect of 3 doses of maternal vitamin D supplementation beginning in gestation and continued in lactation on infant serum 25(OH)D and compared the prevalence of infant serum 25(OH)D cutoffs (>30, >40, >50, and >75 nmol/L) by dose at 8 wk of age. Design: Pregnant women (n = 226) were randomly allocated to receive 10, 25, or 50 µg vitamin D3/d from 13 to 24 wk of gestation until 8 wk postpartum, with no infant supplementation. Mother and infant blood was collected at 8 wk postpartum. Results: At 8 wk postpartum, mean [nmol/L (95% CI)] infant 25(OH)D at 8 wk was higher in the 50-µg/d [75 (67, 83)] than in the 25-µg/d [52 (45, 58)] or 10-µg/d [45 (38, 52)] vitamin D groups (P < 0.05). Fewer infants born to mothers in the 50-µg/d group had a 25(OH)D concentration,30 nmol/L (indicative of deficiency) than infants in the 25- and 10-µg/d groups, respectively (2% compared with 16% and 43%; P< 0.05). Fewer than 15% of infants in the 10-or 25-µg/d groups achieved a 25(OH)D concentration .75 nmol/L compared with 44% in the 50-µg/d group (P < 0.05). Almost all infants (w98%, n = 44) born to mothers in the 50-µg/d group achieved a 25(OH)D concentration .30 nmol/L. At 8 wk postpartum, mean maternal 25(OH)D concentration was higher in the 50-µg/d [88 (84, 91)] than in the 25-µg/d [78 (74, 81)] or 10-µg/d [69 (66, 73)] groups (P< 0.05). Conclusions: Maternal supplementation beginning in gestation with 50 µg vitamin D3/d protects 98% of unsupplemented breastfed infants against 25(OH)D deficiency (<30 nmol/L) to at least 8 wk, whereas 10 or 25 µg vitamin D/d protects only 57% and 84% of infants, respectively. This trial was registered at clinicaltrials.gov as NCT01112891. [ABSTRACT FROM AUTHOR]

Previous research indicates that circulating vitamin D levels are low in many otherwise healthy adults and that there is considerable seasonal variation in 25-hydroxyvitamin D 125(OH)D] concentrations at high latitudes. We examined seasonal variation in 25(OH)D levels in a sample of young adults of diverse ancestry living in the Greater Toronto Area. Three hundred and fifty-one 1351) healthy young adults completed both a fall and winter visit during this study. The study was conducted over 2 y )y 1: fall 2007 to winter 2008 andy 2: fall 2008 to winter 2009). At both visits, each participants serum 25(OH)D concentration was measured. Information was also obtained on skin pigmentation (measured via reflectometer), vitamin D intake, and extent of sun exposure. Overall, the serum 25(OH)D concentration was 54.4 ± 1.3 nmol/L in the fall and 38.4 ± 1.1 nmol/L in the winter. Concentrations differed among ancestral groups at both visits (P < 0.001), with South Asians and East Asians having substantially lower concentrations than Europeans. Skin pigmentation 1r2 = 0.14; p < 0.001), supplemental vitamin D intake (r2 = 0.09; P< 0.0011, sun exposure (r2= 0.04; P< 0.001), and study year )r2 = 0.02; P= 0.0171 were predictors of fall 25(OH)D concentrations. During the wintertime, serum 25(OH)D concentrations were associated with concentrations taken in the fall (r2 = 0.45; P < 0.001), supplemental (r2 = 0.15; P < 0.001) and dietary vitamin D intake (r2 = 0.06; P < 0.001), and with study year = 0.02; P = 0.009). Our study confirms that serum 25(OH)D concentrations undergo strong seasonal variation at high latitudes and are influenced by vitamin D intake, skin pigmentation, and sun exposure. [ABSTRACT FROM AUTHOR]

In North America, there is increasing public health awareness of the importance of adequate vitamin D intake to the maintenance of optimal vitamin D status and overall health. Experts now define this as circulating levels of 25-hydroxyvitamin D of 75-80 nmol/L. This serum level and high levels of dietary intake have been associated with significantly reduced risk of chronic diseases, such as osteoporosis, cardiovascular disease, diabetes, and some cancers. All of these diseases are more prevalent in the elderly of all races, and some are more prevalent and of greater severity among blacks than whites. Our objective is to review recent actions to increase public awareness of the health importance of maintaining optimal circulating 25(OH)D and potential strategies to increase vitamin D intake. Clinicians and educators are encouraged to promote improved vitamin D intake and status, particularly among the elderly and blacks. This will largely depend on combined efforts to judiciously fortify our food supply and to develop individual supplementation protocols for supplements or controlled use of UV light exposure to maintain optimal serum 25(OH)D, especially in high-risk groups. Growing evidence supports a low risk of toxicity with vitamin D use in fortification or supplementation, despite its past reputation of potential toxicity in excess. The cost to fortify food or supplements with vitamin D is relatively inexpensive compared with developing drugs used to treat or prevent chronic diseases; moreover, there is significant potential for broad health benefits in the reduced risk and prevention of multiple chronic diseases. [ABSTRACT FROM AUTHOR]

Global high prevalence of vitamin D insufficiency and re-emergence of rickets and the growing scientific evidence linking low circulating 25-hydroxyvitamin D to increased risk of osteoporosis, diabetes, cancer, and autoimmune disorders have stimulated recommendations to increase sunlight (UVB) exposure as a source of vitamin D. However, concern over increased risk of melanoma with unprotected UVB exposure has led to the alternative recommendation that sufficient vitamin D should be supplied through dietary sources alone. Here, we examine the adequacy of vitamin D intake worldwide and evaluate the ability of current fortification policies and supplement use practices among various countries to meet this recommendation. It is evident from our review that vitamin D intake is often too low to sustain healthy circulating levels of 25-hydroxyvitamin D in countries without mandatory staple food fortification, such as with milk and margarine. Even in countries that do fortify, vitamin D intakes are low in some groups due to their unique dietary patterns, such as low milk consumption, vegetarian diet, limited use of dietary supplements, or loss of traditional high fish intakes. Our global review indicates that dietary supplement use may contribute 6-47% of the average vitamin D intake in some countries. Recent studies demonstrate safety and efficacy of community-based vitamin D supplementation trials and food staple fortification introduced in countries without fortification policies. Reliance on the world food supply as an alternative to UVB exposure will necessitate greater availability of fortified food staples, dietary supplement use, and/or change in dietary patterns to consume more fish. [ABSTRACT FROM AUTHOR]

From its inaugural value in 1941, the Recommended Dietary Allowance (RDA) for adults for vitamin D has remained close to 400 IU (10 microg) level. This original recommended intake was based on the observation that the amount of vitamin D activity in a teaspoon of cod liver oil was sufficient to prevent rickets in infants. Since that time until 1997, determination of vitamin D requirements and status was more conjecture than science. In 1997, when the recommended intake level of vitamin D was set as an adequate intake value rather than an RDA, much has been learned about metabolism of vitamin D. The circulating metabolite 25-hydroxyvitamin D is the major static indicator of vitamin D status. Using its response to diet in the absence of sun exposure, a dose-response study suggests a mean requirement of at least 500 IU (12.5 microg) from which an RDA could be set. Other factors may need adjustment, such as sun exposure and body fat. However, functional indicators of status are needed. The role of vitamin D in calcium metabolism (i.e., calciotropic functions) is better understood; bone turnover and parathyroid hormone are potential indicators. Vitamin D has noncalciotropic functions arising from extrarenal synthesis of the active metabolite 1,25 dihydroxyvitamin D involving cell proliferation and immunity, from which function indicators of status may be derived. Despite gaps in our knowledge, there are data from which new dietary reference intake values for vitamin D may be set. [ABSTRACT FROM AUTHOR]

The article overviews the proceedings of the 2005 Experimental Biology Symposium titled "Optimizing Vitamin D Intake for Populations with Special Needs: Barriers to Effective Food Fortification and Supplementation." The symposium examines the reasons why there are many barriers in the provisions of enough vitamin D foods in compliance of the newly emerging recommendations about vitamin D nutrition. In addition, it also canvasses on the current upper intake level of vitamin D. Concerns on darkly pigmented skin which blocks cutaneous Vitamin D synthesis is also examined.

Presents an overview of the proceedings from Experimental Biology 2004 Symposium: Vitamin D Insufficiency: A Significant Risk Factor in Chronic Diseases and Potential Disease-Specific Biomarkers of Vitamin D Sufficiency. Need to reevaluate current dietary reference intakes for Vitamin D; Inability of the food supply to provide adequate Vitamin D in the absence of sunlight; Diet supplementation in infancy to prevent type 1 diabetes.

Mounting evidence from observational and clinical trials indicates that optimal vitamin D reduces the risk of many diseases. We used observational studies and recent data on 25-hydroxyvitamin D [25(OH)D] concentrations of Canadians from Cycle 3 of the Canadian Health Measures Survey to estimate the reduction in disease incidence, mortality rates, and the total economic burden (direct plus indirect) of disease if 25(OH)D concentrations of all Canadians were raised to or above 100 nmol/L. Recently, the mean 25(OH)D concentration of Canadians varied depending on age and season (51–69 nmol/L), with an overall mean of 61 nmol/L. The diseases affected by 25(OH)D concentration included cancer, cardiovascular disease, dementia, diabetes mellitus, multiple sclerosis, respiratory infections, and musculoskeletal disorders. We used 25(OH)D concentration–health outcome relations for breast cancer and cardiovascular disease and results of clinical trials with vitamin D for respiratory infections and musculoskeletal disorders to estimate the reductions in disease burden for increased 25(OH)D concentrations. If all Canadians attained 25(OH)D concentrations>100 nmol/L, the calculated reduction in annual economic burden of disease was $12.5 ± 6 billion on the basis of economic burdens for 2016 and a reduction in annual premature deaths by 23,000 (11,000–34,000) on the basis of rates for 2011. However, the effects on disease incidence, economic burden, and mortality rate would be phased in gradually over several years primarily because once a chronic disease is established, vitamin D affects its progression only modestly. Nevertheless, national policy changes are justified to improve vitamin D status of Canadians through promotion of safe sun exposure messages, vitamin D supplement use, and/or facilitation of food fortification. [ABSTRACT FROM PUBLISHER]