Vitamin K2 is needed for osteoporosis but contraindicated for other conditions e.g. thrombosis 

Vitamin K2(K2), a therapeutic agent osteoporosis, is prohibited for patients with thrombosis who are receiving warfarin (WF). However, because some aged patients with thrombosis have osteoporosis, some patients treated with WF may be administered K2 concomitantly. We investigated here the interactio …

Source: [Interaction of warfarin and vitamin K2 on arterial thrombotic tendency using a rat aorta loop model] – PubMed

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Can Cumadin (Warfarin) aggravate osteoporosis?

Magnesium to prevent and reverse Aurtic stenosis and calcification in general

the SEM data show that the protein-protein cross-linking bonds are the starting sites of calcification. In addition, substitution of Ca2+ cations by Mg2+ cations leads to the formation of amorphous hydroxyapatite, preventing aortic valve stenosis, which suggests that treatment with magnesium salts may reduce stenosis of aortic valves…
iv.iiarjournals.org/content/28/1/91.full

We observed strong, favorable associations between higher self-reported total (dietary and supplemental) magnesium intake and lower calcification of the coronary arteries…
www.ncbi.nlm.nih.gov/pmc/articles/PMC3957229/

Studies showed that a calcium to magnesium intake ratio <2.8 is critical for optimal health, supporting a long-held but non–evidence-based recommendation that the calcium to magnesium ratio should be close to 2. Increasing calcium intakes in the United States since 1977 have resulted in a calcium to magnesium ratio >3.0 since 2000, coinciding with increasing rates of T2D and colorectal cancer. US studies assessing oral magnesium therapy or dietary magnesium intakes showed beneficial effects of dietary magnesium in CVD, T2D, and cancers, although similar studies in populations with lower calcium to magnesium ratios (≥1.7) reported the opposite…
www.ncbi.nlm.nih.gov/pmc/articles/PMC4717874/

 

Vitamin D

does vit D cause calcification of arteries?
according to one article, it could in some settings, not clear when, many other sources point out the benefits of vit d

Vitamin D in Vascular Calcification: A Double-Edged Sword?

#q
How much sun exposure is needed for vit D instead of supplements?

answer from https://www.healthline.com/nutrition/vitamin-d-from-sun#time-of-day

At noon, the sun is at its highest point, and its UVB rays are most intense. That means you need less time in the sun to make sufficient vitamin D (5Trusted Source).

Many studies also show that the body is most efficient at making vitamin D at noon (6Trusted Source7Trusted Source).

For example, in the UK, 13 minutes of midday sunlight exposure during summer three times per week is enough to maintain healthy levels among Caucasian adults (5Trusted Source).

Another study found that 30 minutes ttof midday summer sun exposure in Oslo, Norway was equivalent to consuming 10,000–20,000 IU of vitamin D (8Trusted Source).

The commonly recommended daily dose of vitamin D is 600 IU (15 mcg) (3).

Vitamin D is critical for brain health…