Everyone says we're not getting enough of it, but

what is vitamin D, anyway?

Schematic representation of the biosynthesis of vitamin D.

Vitamin D is photosynthesized in the skin and is also acquired by dietary intake. Two hydroxylation steps in the liver and the kidney are required for vitamin D activation,

thus forming 1,25-dihydroxyvitamin D.

Storage form Active form(Hormone)

VDRE (promoter region of target genes)

Vitamin D receptor (VDR) binds retinoid X receptor (RXR) at the vitamin D receptor element (VDRE) to regulate gene expression.

vitamin D deficiency and/or VDR gene deletion affects the heart, vasculature, and immune system, which may, in turn, contribute to the development of heart failure, hypertension, and increased atherosclerosis.

Decreased VDR Activation

1,25 VD3 binds to the VDR, which then combines with RXR to activate gene

Vitamin D is a Superhero ?

∗Treatment with vitamin D3 or D2. †Including recommended daily allowance. 25-OH D = 25-hydroxyvitamin D.

Categories of Vitamin D Status According to the Institute of Medicine Versus the Endocrine Society

Current Vitamin D GuidelinesSummary of guidelines regarding vitamin D deficiency

screening and supplementation

Note that all threshold and treatment values are to promote optimal serum 25-hydroxyvitamin D levels for bone health, and not the prevention of cardiovascular disease .

a IOM is a US organization, but the IOM Vitamin D report was funded by the US and Canadian governments .b The Endocrine Society recognizes that supplementation up to 10,000 IU/day in people aged 19 years and older may be needed to correct for deficiency .c Risk factors for deficiency include: African-American and Hispanic ethnicity, pregnant or lactating women, older adults with history of falls or fractures, obesity (BMI >30 kg/m2 ), malabsorption syndromes, chronic kidney disease, liver failure, conditions that cause weakening of bone, certain medications including anticonvulsants

Vitamin D and the Heart

Do lower vitamin D levels mean higher risk for cardiovascular disease?

Is Vitamin D a New Therapeutic Option in Coronary Artery Disease?

Do lower vitamin D levels mean higher risk for cardiovascular disease?

A Novel Biomarker for Cardiovascular Disease?

Reciprocal influences of vitamin D deficiency, CVD and cardiovascular risk factors.

Proposed mechanisms by which vitamin D deficiency and highcalcium levels (typically

from calcium supplementation and not dietary calcium sources)

may increase cardiovascular disease risk.

RAAS, reninangiotensin-aldosterone system; VSMC, vascular smooth muscle cell; LV,left ventricular

Vitamin D, Parathyroid Hormone And Cardiovascular Risk :

The Good, The Bad And The Ugly

The vitamin D-dependent parathyroid hormone is considered as the possible actuator of vitamin D effects on cardiovascular risk

(Vitamin D deficiency : A possible driver of T2D)

Published 2 November 2017

In cardiac patients with diabetes, the higher number of stenoticcoronary arteries is associated with lower values of the 25(OH)D.

A group of male cardiac patients with diabetes with significant stenosis in three coronary arteries, hospitalized due to acute coronary syndrome, with a history of previous MI and hyperlipidemia presented the lowest vitamin D level.

Is vitamin D deficiency a risk factor for severe coronary artery disease and acute coronary syndrome?

In this recent article, Lee et al. concluded that participants with coronary artery plaques are likely

to have relatively low vitamin D level. They added some evidence that vitamin D status is

associated with atherosclerosis.

2017

September 2017

Proposed models for the association of biomarkers of vitamin D status with risk of coronary disease.

This study adds to the growing literature indicating that biomarkers of vitamin D status beyond 25(OH)D may have an independent role in cardiovascular disease.

25-hydroxyvitamin D

parathyroid hormone

vitamin D–binding protein

Is Vitamin D a New Therapeutic Option in Coronary Artery Disease?

Meta-analyses on the association between

vitamin D and cardiovascular events and mortality

Pilz, S. et al. (2016) Vitamin D and cardiovascular disease prevention Nat. Rev. Cardiol. doi:10.1038/nrcardio.2016.73

Large, randomized, placebo-controlled trials on

vitamin D treatment effect on cardiovascular outcomes

Pilz, S. et al. (2016) Vitamin D and cardiovascular disease prevention Nat. Rev. Cardiol. doi:10.1038/nrcardio.2016.73

Published online April 5, 2017.

Vitamin D deficiency : “To D, or not to D,that is the question”.

78 pages

What do guidelines say?

Population Recommendation Grade

Community-dwelling, nonpregnant,

asymptomatic adults age 18 years and older

The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for vitamin D

deficiency in asymptomatic adults.

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The Unresolved Controversy

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Let 's go outside andget some sunshine

Vitamin D: How Much Sun Is Good For You?

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