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The Integrative Coronary Heart Disease (CHD) Prevention Program
Published in Mark C Houston, The Truth About Heart Disease, 2023
There are two forms of vitamin K—called K1 and K2—and there are subtypes of each of these. Vitamin K is a fat-soluble vitamin. Vitamin K1 (phylloquinone) is found in plant foods, like leafy greens. Vitamin K2 (menaquinone) is found in animal and fermented foods. However, supplementing with K2 MK 7 is recommended to obtain an adequate blood level in order to prevent CHD, coronary artery calcification, and heart disease. While vitamin K1 is absorbed and used primarily by the liver, vitamin K2 MK 7 is available, and measurable, in the blood. As such, unlike vitamin K1, vitamin K2 does not get sequestered in the liver for only the liver's function. Rather, because it is available in serum blood, it can travel and go to work in other areas of the body.
Vitamin Deficiencies – Diagnosis and Treatment
Published in Jennifer Doley, Mary J. Marian, Adult Malnutrition, 2023
Patients on anticoagulant therapy may require closer monitoring, as warfarin and vitamin K counteract each other. Anticoagulant doses are adjusted to achieve a therapeutic international normalized ratio (INR). INR is calculated based on prothrombin time (PT), which measures how long it takes for a clot to form in a blood sample. Once the goal INR is met, daily vitamin K intake should remain consistent. Without warfarin dose adjustments, increased vitamin K intake leads to an increased risk of blood clots, whereas decreased vitamin K intake could increase the risk of bleeding. The INR is the most common laboratory test used to monitor warfarin therapy and detect potential bleeding problems, while plasma phylloquinone is measured to assess vitamin K status. Normal fasting phylloquinone levels in healthy adults are 0.15 to 1.0 μg/L.1
Micronutrients
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
People are generally encouraged to get their daily requirement of vitamin K through dietary foods because deficiency in vitamin K is rare. In addition, fat-soluble vitamins A, D, E, and K, are stored long-term in the body’s fat tissues, and can cause hypervitaminosis, which is toxic for the body. Vitamin K1 (phylloquinone) is present primarily in green leafy vegetables because it is synthesized in plants through photosynthesis. Vitamin K1 is the main dietary form of vitamin K. Vitamin K2 (menaquinones) have several related chemical subtypes with different unsaturated isoprenyl side chains and are designated as MK-4 through MK-13, based on the length of their side chain. MK-4, MK-7, and MK-9 are the most well studied menaquinones (3, 9, 33, 82–88). Menaquinones, which are predominantly of bacterial origin, are present in modest amounts in various animal-based and fermented foods. Almost all menaquinones, in particular the long-chain menaquinones, are also produced by bacteria in the human gut (82).
Vitamin K status and inflammation are associated with cognition in older Irish adults
Published in Nutritional Neuroscience, 2020
A. Kiely, G. Ferland, B. Ouliass, P.W. O’Toole, H. Purtill, E.M. O’Connor
Analysis of Covariance (ANCOVA) was used to examine differences in dietary phylloquinone, serum phylloquinone and inflammatory blood markers (IL-6, IL-8, IL-10, TNFα and high-sensitivity C-Reactive) Protein (hsCRP) across the MMSE categories, controlling for sex, age, BMI, triglycerides and blood pressure. Bonferroni adjusted pairwise comparisons were used to examine between-group differences. Partial correlations were used to examine the linear relationships between dietary phylloquinone, serum phylloquinone and the inflammatory blood markers (IL-6, IL-8, IL-10 and TNFa), controlling for sex, age, BMI, triglycerides and blood pressure. All positively skewed data were normalised using a natural logarithm transformation prior to analyses. Diastolic blood pressure was used as the control variable for blood pressure throughout the analyses.
Vitamin K Deficiency in the Setting of Blenderized Tube Feeding Regimen in a Teenager: A Case Report
Published in Journal of Dietary Supplements, 2023
N. Khan, M. Taimur, A. Malkani, R. Lamsal
Vitamin K is a naturally occurring fat-soluble vitamin that exists in two dietary forms- K1(phylloquinone) and K2 (menaquinone). Phylloquinone is the main dietary and circulatory form of vitamin K which is primarily found in green-leafy vegetables such as broccoli, spinach, iceberg lettuce, soybean, and vegetable oil (1). Menaquinone is found in meat, dairy products, eggs and is also synthesized by the gut bacteria in amounts not sufficient to meet the human requirement (2). Vitamin K functions as an important cofactor for the synthesis and normal functioning of clotting factors II, VII, IX, X and proteins C and protein S in the liver (1).
Dietary vitamin K is remodeled by gut microbiota and influences community composition
Published in Gut Microbes, 2021
Jessie L. Ellis, J. Philip Karl, Angela M. Oliverio, Xueyan Fu, Jason W. Soares, Benjamin E. Wolfe, Christopher J. Hernandez, Joel B. Mason, Sarah L. Booth
Vitamin K may be an underappreciated mediator of both diet-gut microbiota interactions and gut microbiota community dynamics. Whereas phylloquinone (PK) is a dietary vitamin K quinone found in plants,8 menaquinones (MKn) are vitamin K quinones that are both consumed in the diet and produced by the gut microbiota.9 All vitamin K quinones share a common naphthoquinone ring structure, but vary in the length and saturation of their sidechains (Figure 1a). MKn are used as electron carriers in bacterial respiration, and quinone synthesis is widespread in the gut.10 Some bacterial taxa have lost critical genes in MKn biosynthetic pathways, but still possess quinone-dependent terminal reductases, suggesting a retained capacity for respiration.10 Recent work demonstrated that a “growth factor” secreted from neighboring bacteria enabled the growth of previously uncultured human gut bacterial species, and the growth factor was identified to be MKn.11 Interestingly, although PK is not a bacterially produced vitamin K form, it has also been demonstrated in vitro to be a growth factor for some species of bacteria.12,13 These results together suggest some species in the human gut microbiota that have lost the ability to synthesize MKn may be able to utilize vitamin K quinones or precursors originating from neighboring bacteria or from the host diet. This would represent a tradeoff of a metabolically expensive synthesis pathway in favor of microbe-microbe or diet-microbe dependencies, which could, in turn, influence community stability and metabolic activity within the gut microbiota. However, to the best of our knowledge this concept has never been tested in vivo, nor has an intersection with host nutrition (specifically, dietary vitamin K quinones) been considered.