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Vitamin D status: measurement, interpretation, and clinical application. Holick MF. Ann Epidemiol. 2009 Feb;19(2):73-8. Epub 2008 Mar 10. Review. PMID: 18329892 Conclusion The only way to determine whether a person is vitamin D deficient or sufficient is to measure their circulating level of 25(OH)D. There are a variety of assays used to measure 25(OH)D. The radioimmunoassays and competitive protein binding assays for 25(OH)D are useful in detecting vitamin D deficiency and sufficiency. However, these assays are fraught with technical difficulties, especially if they are not run routinely (Fig. 4) (33). Several reference laboratories have now switched to LC-MS ,which measures both 25(OH)D2 and 25(OH)D3 quantitatively. The total 25(OH)D, i.e., 25(OH)D2 plus 25(OH)D3, is what physicians need to be aware of for their patients. A level >30 ng/mL is

Serum 25-hydroxyvitamin D status of the US population: 1988-1994 compared with 2000-2004. Looker AC, Pfeiffer CM, Lacher DA, Schleicher RL, Picciano MF, Yetley EA. Am J Clin Nutr. 2008 Dec;88(6):1519-27. PMID: 19064511 doi:10.3945/ajcn.2008.26182 Conclusions: Overall, mean serum 25(OH)D was lower in 2000-2004 than 1988-1994. Assay changes unrelated to changes in vitamin D status accounted for much of the difference in most population groups. In an adult subgroup, combined changes in BMI, milk intake, and sun protection appeared to contribute to a real decline in vitamin D status. In summary, age-standardized mean serum 25(OH)D concentrations based on observed values were significantly lower in 2000-2004 than in 1988-1994 in all groups examined. Adjustment for assay changes noticeably reduced the difference between surveys. However, mean serum 25(OH)D concentrations remained significantly lower in males (except Mexican Americans) in NHANES 2000-2004 than in NHANES III, even after adjustment for assay differences. This remaining difference likely represents a real decline in vitamin D status. Changes in BMI, milk intake, and sun protection appeared to contribute to this decline in a subgroup of non-Hispanic white adults. The possibility that trends in overweight, sun protection, and milk intake may continue supports the need to continue monitoring the serum 25(OH)D status of the population

Using a new, more sensitive-testing approach they developed for fungi, Penn State food scientists have found that mushrooms are a better natural source of the antioxidant ergothioneine than either of the two dietary sources previously believed to be best. The researchers found that white button mushrooms, the most commonly consumed kind in the U.S., have about 12 times more of the antioxidant than wheat germ and 4 times more than chicken liver, the previous top-rated ergothioneine sources based on available data. Until the Penn State researchers developed their testing approach, known as an assay, there was no method employing the most sensitive modern instrumentation and analytical techniques to quantify the amount of ergothioneine in fungi. The researchers say that their assay can be used for other plants, too, not just mushrooms.

Effectiveness and safety of vitamin D in relation to bone health. Cranney A, Horsley T, O'Donnell S, Weiler H, Puil L, Ooi D, Atkinson S, Ward L, Moher D, Hanley D, Fang M, Yazdi F, Garritty C, Sampson M, Barrowman N, Tsertsvadze A, Mamaladze V. Evid Rep Technol Assess (Full Rep). 2007 Aug;(158):1-235. Review. PMID: 18088161 CONCLUSIONS: The results highlight the need for additional high quality studies in infants, children, premenopausal women, and diverse racial or ethnic groups. There was fair evidence from studies of an association between circulating 25(OH)D concentrations with some bone health outcomes (established rickets, PTH, falls, BMD). However, the evidence for an association was inconsistent for other outcomes (e.g., BMC in infants and fractures in adults). It was difficult to define specific thresholds of circulating 25(OH)D for optimal bone health due to the imprecision of different 25(OH)D assays. Standard reference preparations are needed so that serum 25(OH)D can be accurately and reliably measured, and validated. In most trials, the effects of vitamin D and calcium could not be separated. Vitamin D(3) (>700 IU/day) with calcium supplementation compared to placebo has a small beneficial effect on BMD, and reduces the risk of fractures and falls although benefit may be confined to specific subgroups. Vitamin D intake above current dietary reference intakes was not reported to be associated with an increased risk of adverse events. However, most trials of higher doses of vitamin D were not adequately designed to assess long-term harms.

Effectiveness and safety of vitamin D in relation to bone health. Cranney A, Horsley T, O'Donnell S, Weiler H, Puil L, Ooi D, Atkinson S, Ward L, Moher D, Hanley D, Fang M, Yazdi F, Garritty C, Sampson M, Barrowman N, Tsertsvadze A, Mamaladze V. Evid Rep Technol Assess (Full Rep). 2007 Aug;(158):1-235. Review. PMID: 18088161 CONCLUSIONS: The results highlight the need for additional high quality studies in infants, children, premenopausal women, and diverse racial or ethnic groups. There was fair evidence from studies of an association between circulating 25(OH)D concentrations with some bone health outcomes (established rickets, PTH, falls, BMD). However, the evidence for an association was inconsistent for other outcomes (e.g., BMC in infants and fractures in adults). It was difficult to define specific thresholds of circulating 25(OH)D for optimal bone health due to the imprecision of different 25(OH)D assays. Standard reference preparations are needed so that serum 25(OH)D can be accurately and reliably measured, and validated. In most trials, the effects of vitamin D and calcium could not be separated. Vitamin D(3) (>700 IU/day) with calcium supplementation compared to placebo has a small beneficial effect on BMD, and reduces the risk of fractures and falls although benefit may be confined to specific subgroups. Vitamin D intake above current dietary reference intakes was not reported to be associated with an increased risk of adverse events. However, most trials of higher doses of vitamin D were not adequately designed to assess long-term harms.

A vitamin D nutritional cornucopia: new insights concerning the serum 25-hydroxyvitamin D status of the US population. Norman AW. Am J Clin Nutr. 2008 Dec;88(6):1455-6. PMID: 19064502 doi:10.3945/ajcn.2008.27049 In summary, the report of Looker et al should be required reading for all nutritionists, clinicians, and vitamin D aficionados who are decision makers with regard to 25(OH)D assays, vitamin D nutritional policy, and the care of patients with vitamin D-related diseases.

Mechanisms of berberine (natural yellow 18)-induced mitochondrial dysfunction: interaction with the adenine nucleotide translocator. Pereira CV, Machado NG, Oliveira PJ. Toxicol Sci. 2008 Oct;105(2):408-17. Epub 2008 Jul 3. PMID: 18599498 doi: 10.1124/jpet.107.128017 The data from the present work appear to show that berberine also presents some degree of toxicity to "nontumor" systems, which should be carefully understood. ANT inhibition in nontumor cells by berberine would be responsible for a decrease in energy production and could also result in MPT induction. To the best of our knowledge, no full toxicity assessment exists for berberine in humans, although its use in several commercially available supplements suggests that the compound may present a relatively wide safety interval. In fact, a study with patients with congestive heart failure treated with 1.2 g/day of oral berberine revealed low toxicity and resulted into an average plasma concentration of 0.11 mg/l which would translate into 0.3µM (Zeng and Zeng, 1999Go). Repeated cumulative treatments, alternative forms of formulation (e.g., topical application vs. injection) or more importantly, active mitochondrial accumulation due to its positive charge would be expected to increase its concentration in cells into the range of concentrations used in this study. Empirical data from nontraditional medicines plus the use of extensive clinical assays would allow the use of berberine as a promising antimelanoma agent while maintaining its safety for humans. In radial/vertical forms of melanoma, a possible topical application of berberine would also be possible, thus minimizing side effects on other organs. In conclusion, the present work identifies the ANT as an important target for berberine, with clear relevance for its proposed antitumor effects.

An international comparison of serum 25-hydroxyvitamin D measurements. Lips P, Chapuy MC, Dawson-Hughes B, Pols HA, Holick MF. Osteoporos Int. 1999;9(5):394-7. PMID: 10550457 DOI: 10.1007/s001980050162 The results show that 25(OH)D values from different laboratories can not be assumed to be comparable unless a careful cross-calibration has been performed.