The combination of vitamins K2 and D3 has been shown to significantly increase bone mineral density (BMD) better than either vitamin alone (AlHajri et al., 2021). A high dose of vitamin K2 has been shown to significantly reduce fractures in double-blind research of postmenopausal women with osteopenia (Cheung et al., 2008). A review of seven controlled studies confirmed that a high dose of vitamin K2 reduces the risk of fractures, and preliminary research has shown that large amounts of vitamin K2 correlate with greater BMD and increase bone formation in some women (AlHajri et al., 2021). Vitamin K2 also supports the activation of proteins involved in tooth mineralization.
MK-7, the form of vitamin K2 in Vitamin K2+A+D3, has been shown to significantly reduce loss of BMD and improve bone strength in placebo-controlled research (AlHajri et al., 2021). K2 has also been shown to improve the ratio of bone formation to bone breakdown (AlHajri et al., 2021). A meta-analysis of 32 studies found that 500–1000 IU of daily vitamin D3 supplementation may reduce the risk of fracture by 13% (Kong et al., 2022). A meta-analysis of eight controlled studies found that vitamins D3 and K2 together help significantly increase bone density (AlHajri et al., 2021).
Vitamins D3 and A benefit the eyes and skin. People with the highest vitamin D levels are 36% less likely to have macular degeneration (Parekh et al., 2007). Vitamin A deficiency may cause, and supplementation may improve, night blindness. Doubleblind research shows that high-dose vitamin A can speed up recovery of light sensitivity and adaptation to dark (Owsley et al., 2006).
Vitamin D3 can help treat eczema in adults with low levels of D (Samochocki et al., 2013), and high-dose vitamin A has been shown to prevent acne (Kligman et al., 1981). People with the highest levels of vitamin D also have 20% less risk of gingivitis (Dietrich et al., 2005). Impressively, vitamin D has been found to reduce the risk of flu in children by 42% during the winter (Urashima et al., 2010). Both vitamin A and vitamin D play multiple roles in immune health (Cantorna et al., 2019).
