From the Guidelines
Vitamin K2 and vitamin D supplementation together may have a synergistic effect on bone health, but the current evidence does not specifically support their combined use for fracture prevention or other health outcomes, as the provided studies primarily focus on the effects of calcium and vitamin D supplementation. When considering the effects of vitamin D supplementation, a Cochrane review 1 found that vitamin D alone is unlikely to be effective in preventing hip fracture or any new fracture. However, the combination of vitamin D and calcium has been shown to result in a small reduction in hip fracture risk and a reduction in the incidence of new nonvertebral fractures 1. The optimal dosage and formulation of vitamin K2 and vitamin D supplements are not well established, but typical recommended daily intakes are 100-200 mcg for vitamin K2 and 1,000-5,000 IU for vitamin D. Some key points to consider when taking these supplements together include:
- Consuming them with a meal containing some fat to enhance absorption, as both are fat-soluble vitamins
- Potential interactions with blood thinners like warfarin, which may require consultation with a healthcare provider
- Regular blood tests to monitor vitamin D levels if supplementing long-term It is essential to consult with a healthcare provider before starting any supplement regimen, especially for individuals with specific medical conditions or taking medications that may interact with vitamin K2 or vitamin D. In terms of exercise and bone health, a Cochrane review 1 found that high-force exercise, such as progressive resistance strength training, seems to be ineffective in improving BMD in postmenopausal women, while combination exercise programs may be more effective. For cancer survivors, exercise may not be sufficient to improve bone health, but combined resistance and impact exercise interventions may have a positive effect on lumbar spine BMD 1. Overall, while vitamin K2 and vitamin D may have potential benefits for bone health, the current evidence does not provide strong support for their combined use, and individualized recommendations should be based on a person's specific needs and health status.
From the Research
Effect of Vitamin K2 with Vitamin D on Bone Health
- The combination of Vitamin K2 and Vitamin D has been shown to increase bone mineral density (BMD) in postmenopausal women with osteoporosis 2, 3.
- Vitamin K2 supplementation has been found to contribute to the structural integrity of osteocalcin, a major non-collagenous protein in bone matrix, and enhance the association of calcium and Vitamin D with bone health 4.
- A meta-analysis of randomized controlled trials found that the combination of Vitamin K and Vitamin D significantly increased total BMD and decreased undercarboxylated osteocalcin 3.
- Treatment with Vitamin D3 and/or Vitamin K2 has been found to sustain lumbar BMD and prevent osteoporotic fractures in postmenopausal women with osteoporosis 5.
Specific Studies on Vitamin K2 and Vitamin D
- A study published in 2000 found that the combined administration of Vitamin D3 and Vitamin K2 increased BMD of the lumbar spine in postmenopausal women with osteoporosis 2.
- A 2020 meta-analysis found that Vitamin K combined with Vitamin D significantly increased total BMD and decreased undercarboxylated osteocalcin 3.
- A 2021 clinical trial found that treatment with Vitamin K2 (MK-7) as an add-on to calcium and Vitamin D supplementation increased carboxylation of osteocalcin, but did not affect biochemical markers of bone turnover, bone mineral density, or bone microarchitecture in postmenopausal women with osteopenia 6.
Key Findings
- The combination of Vitamin K2 and Vitamin D may be more effective than treatment with Vitamin K2 alone in increasing BMD and preventing osteoporotic fractures 2, 5.
- Vitamin K2 supplementation may be beneficial in preserving bone quality and strength in postmenopausal women with osteoporosis 4, 5.
- Further research is needed to fully understand the effects of Vitamin K2 and Vitamin D on bone health and to determine the optimal dosage and treatment duration 3, 6.