The Benefits of Vitamin K for Diabetes

vegetables An important aspect of diabetes is blood plasma glucose, and controlling that is one of the highest priorities for diabetics everywhere. Changes in lifestyle and diet are key to controlling blood glucose levels. Most of the conversations about this topic are rightfully centered around glucose - the glycemic index and glycemic load of foods - and often micro-nutrients (such as the less “prime time” vitamins and minerals) are added as an after-thought to the central conversations.

Although not always discussed, many of the micro-nutrients are crucially needed by the body for both protection and restoration of normal function. Given the interconnected and complex ways in which the body’s organs and systems are connected, it is important to get all the nutrition needed by every function to reduce the impact of diabetes on the body.

In this article we will explore the role of Vitamin K in glucose homeostasis based on recent (and not-so-recent) research findings.

What is Vitamin K?

Vitamin K (VK) is not a single compound, rather it is a group of compounds that can be found in the foods we eat, as well as produced by some awesome bacteria in our guts [1]

There are two general groups, VK1 (phylloquinone), which is found in green leafy vegetables, and VK2 (menaquinone), which is found in dairy products and fermented foods, as well as produced by some gut bacteria.

For adult men and women over the age of 18, 120 micro-grams(mcg) and 90 micro-grams(mcg) of Vitamin K respectively is the daily adequate intake recommendation [2].

While you can get all your vitamin K needs from a proper diet, supplementation is still an option that a doctor might recommend. It is important to note that VK is a fat soluble compound and can pose a greater risk for toxicity when too much is consumed. This is in contrast to water soluble vitamins, like the B vitamins, that the body can more readily wash out through excretion.

Why is Vitamin K important for Diabetics?

In general, VK supports the creation of many proteins that are responsible for blood coagulation and clotting, bone health and strength, and heart arterial health through matrix Gla proteins (MGP).

In Diabetes Mellitus (DM) patients, a number of recent studies have shown that VK circulating in the blood is positively correlated with plasma insulin levels. Sakamoto et al., demonstrated this with a group of 25 healthy young male volunteers with varying VK dietary intake. The participants were divided into separate groups representing their average VK intake and blood VK content, and given an oral dose of 75g of glucose. The researchers showed that, consistently, individuals with higher blood VK had lower plasma glucose and a higher insulinogenic index.

Several other studies [3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13] in human and other animal models, arrive at similar results; vitamin K is positively correlated to improved glucose homeostasis and/or reduction in the risk of complications from diabetes.

Possible explanations for the effects Researchers have a few hypotheses to explain the effects of VK on the observed insulin response and improved glucose tolerance. Without getting too technical, possible explanations include:

  1. Insulinotropic Effects [14,15,16,17]: A recent study has shown that MK-4, a homolog of VK2, amplified the glucose-stimulated insulin secretion in mice. This indicates that MK-4 might have the same effect as other gut peptides that are released after a meal to stimulate insulin production.
  2. Modulation of VK-dependent proteins (VKDPs) [18, 19,20,21,22,23,24,25, 26, 27]: VK-dependent proteins (VKDPs), are responsible for many bodily functions, including reducing the risk of arterial calcification, which has been observed in Type 2 DM patients. Furthermore, other studies report a specific VKDP (osteoblast-specific secreted osteocalcin) in involved in the regulation of glucose metabolism.
  3. Prevention of Inflammation [28, 29, 30 ]: Many reports have indicated that insulin sensitivity in adipose tissue is affected by the presence/absence of inflammatory cytokines (TNF-α, IL-1, IL-6). Some research has shown an association between high plasma VK1 concentration and intake with significant suppression of the inflammatory cytokines.

Lastly, new research is uncovering an increasing amount of evidence indicating that VK has protective and restoration properties on diabetic complications such as; Cataracts - through inhibiting a key enzyme (ALR2) in cataract formation; Diabetic Nephropathy - evidence showing MGP (a VKDP) plays a renoprotective role; Diabetic Peripheral Neuropathy - evidence shows plasma dpucMGP (inactive form of the VK-dependent protein MGP) levels increased in patients with low VK and with diabetic peripheral Neuropathy; Cardiovascular Disease (CVD) - many reports associate improved cardiovascular health with VK intake and reduced risk of vascular calcification with increased VKDP activity.

This article is intended to outline the importance of vitamin K and its impact on the body, and hopefully shines a light on some of the open questions in current cutting-edge research. There is a lot of promise in new therapies for diabetes control, and VK is proving itself a formidable force against diabetes mellitus.

This article draws directly from decades of amazing research, all of which are referenced as used above. A key resource has been one by Ho, Komai, and Shirakawa (2020), and can be found here