Vitamin K2 also called menaquinone has nine associated compounds which are generally subdivided into short chain menaquinones and long chain menaquinones of MK-7, MK-8 and MK-9 are nutritionally most recognized. Menaquinones are abbreviated as MK-n where M refers menaquinone, K stands for Vitamin K and n represents number of isoprenoid side chain residues. Menaquinone-7 and other long chain menaquinones vary from MK-4 in that they are not formed by human tissue. MK-7 could be transformed from phylloquinone (K1) in the colon by Escherichia coli bacteria. These menaquinones are incorporated by bacteria in gut to subsidize overall vitamin K status.
Vitamin K2 is a form of Vitamin K which is crucial for maintaining healthy bones. Besides calcium, body requires Vitamin K2 which activates two proteins to regulate. Various dietary sources such as eggs, meat and various cheeses incorporate Vitamin K2.
Types of Vitamin K2
Vitamin K is found in two forms: Vitamin K1 and Vitamin K2. Vitamin K2 is a type of vitamin required for maintaining strong bones. There are several forms of Vitamin K2:
- MK-4
The structure of MK-4 resembles Vitamin K1. So the body uses it in similar way, MK-4 is used by the body to activate blood clotting proteins in liver. The leftover is packaged inside triglycerides and transport to bloodstream. Leftover MK-4 will support bones. MK-4 does not stick for long and is cleared from bloodstream in 6 to 8 hours.
- MK-7
Unlike Vitamin K1 and MK-4, Vitamin MK-7 is structurally different. So the use by the body also differs. Vitamin MK-7 is absorbed in small intestine before moved to the liver. MK-7 is packaged in LDL cholesterol and is sent to bloodstream. Then it activates proteins which guide calcium to the bones and keep out of arteries, organs and soft tissues. LDL cholesterol disseminate in the body for several days. Literally, MK-7 remains in the body for upto 4 days. It has longer half-life which means one could build steady level when consumed regularly.
MK-7’s much longer availability is the reason a small dose – as little as 90 micrograms per day – may be all you need to optimize your body’s ability to activate osteocalcin and matrix Gla protein.
Food Sources
| Food name | Weight (g) | Vitamin K2 (µg) |
| Meatballs | 85 | 23.9 |
| Chicken | 113 | 22 |
| Kielbasa | 85 | 17.1 |
| Swiss cheese | 132 | 8.3 |
| Parmesan cheese | 100 | 7.1 |
| Mozzarella cheese | 228 | 4.8 |
| Queso fresco cheese | 122 | 4.4 |
| Oyster | 85 | 4.2 |
| Salami | 12.3 | 3.4 |
| Tamales | 113 | 3.1 |
| Quinoa | 170 | 1.9 |
| Cheddar cheese | 19 | 1.6 |
| Cream cheese | 14.5 | 1.3 |
| Potatoes | 229 | 1.1 |
| Plantains, yellow | 169 | 1 |
| Butter | 3.8 | 0.8 |
| Sour cream | 12 | 0.7 |
| Spinach | 136 | 0.4 |
| Portabella mushroom | 121 | 0.4 |
| Sockeye salmon | 85 | 0.3 |
Health Benefits of Vitamin K2
- Use of calcium
Vitamin K2 helps control the accumulation of calcium in the body. Vitamin K2 is beneficial for heart, skeleton, nervous system and teeth by regulating use of calcium in bones, teeth and arteries. Vitamin D is responsible to transport calcium from intestines as it digests in the bloodstream. Vitamin K2 activates osteocalcin when takes calcium out of bloodstream and deposits it into bones and teeth. This vitamin also involves in maintaining structures of arterial walls, teeth, osteoarticular system and regulation of cell growth.
- Cardiovascular health
Vitamin K2 is beneficial for men as it offers protection against heart associated problems such as atherosclerosis which are the major cause of death in developed countries. Adequate Vitamin K2 helps to lower the chances of vascular damage as it activates matrix GLA protein inhibiting deposits of calcium on the walls.
Intake of Vitamin K2 is associated to lowering the chances of aortic calcification. Men consuming K2 lowers 52 percent of severe aortic calcification and 41 percent lowers the chances of coronary heart disease. Vitamin K2 could reverse buildup of plaque in arteries making it effective to treat heart disease.
- Healthy bones and teeth
Vitamin K2 is beneficial for skeletal system by using calcium and lead to teeth and bones making them solid and strong. Number of studies shows that Vitamin K2 is useful in preventing and treating fractures, bone loss and osteoporosis. Studies show that Vitamin K2 slows down rate of bone loss in adults and helps to promote bone mass. It promotes osteocalcin accumulation in exracellular matrix of osteoblasts inside bones that promotes bone mineralization. In animal studies, it combat bone loss experienced during menopause. It maintains structure of teeth and jaws. Vitamin K2 foods are used in diets which help in prevent cavities, plaque formation and tooth decay. During pregnancy, Vitamin K2 is required for fetal growth.
- Cancer prevention
Those with high Vitamin K2 in diet have low chances of being prone to cancer and death from cancer. Vitamin K2 prevents growth of leukemia, lung, prostate and liver cancer.
- Rheumatoid arthritis damage
Patients having rheumatoid arthritis shows that supplements with vitamin K2 results in slowdown of bone mineral density loss and lowers the chances of RANKL which is an inflammatory compound found in the blood of subjects. Vitamin K2 is useful for rheumatoid arthritis diet.
- Improves hormonal balance
Vitamin K2 could produce osteocalcin hormone having positive metabolic and hormonal effects. Fat soluble vitamins are required for production of reproductive or sex hormones including testosterone and estrogen. Due to its hormonal balancing effects, women having polycystic ovarian syndrome found Vitamin K2 beneficial when added to diet. It enhances blood sugar balance and insulin sensitivity that lowers the chances of metabolic problems such as obesity. It regulates glucose metabolism by modulating osteocalcin and proinflammatory pathways.
- Kidney health
Vitamin K2 is helpful for kidneys which prevents formation of calcium accumulation in wrong places which is the major cause of kidney stones. Deficiency of Vitamin D and K2 is related with high chances of kidney disease.
- Prevent wrinkles
Elastin and collagen are two components of skin providing firmness and elasticity. Elastin and collagen are two components of skin providing firmness and elasticity. As people ages, it loses elastin and collagen and its youthful appearance. Skin cells releases matrix-GLA protein in order to prevent calcification of elastin in skin. Elastin is calcified due to lack of Vitamin K2 activated matrix-GLA protein. It maintains youthful skin activating matrix-GLA and prevents calcification of elastin.
- Prevent varicose veins
Vitamin K2 activates matrix-GLA protein to payoff calcium in vessels and shows cardiovascular benefits. Veins calcification is a major contributor to varicose veins so Vitamin K2 helps in preventing varicose veins.
- Enhance exercise performance
During exercise, bones releases osteocalcin which seems to send out messages to assist muscles cope with increased energy demands. Vitamin K2 allows skeletal muscle to use energy during exercise and increase efficiency of workout and potential performance.
Recommended Intake of Vitamin K
The recommended dietary allowance (RDA) for Vitamin K2 is not known yet. Research shows that 360 micrograms a day in form of MK-7 is certainly effective, and as 90 micrograms could be adequate for people with osteoporosis and osteopenia.
| Life Stage | Age | Females(mcg/day) | Males(mcg/day) |
| Infants | 0-6 months | 2 | 2 |
| Infants | 7-12 months | 2.5 | 2.5 |
| Children | 1-3 yrs | 30 | 30 |
| Children | 4-8 yrs | 55 | 55 |
| Children | 9-13 yrs | 60 | 60 |
| Adolescents | 14-18 yrs | 75 | 75 |
| Adults | 19+ yrs | 90 | 120 |
| Pregnancy | 18+ yrs | 75 | – |
| Pregnancy | 19+ yrs | 90 | – |
| Breastfeeding | 18+ yrs | 75 | – |
| Breastfeeding | 19+ yrs | 90 | – |
Deficiency and toxicity
- Vitamin K2 deficiency results heart problems such as high blood pressure, arterial calcification, cavities or dental issues, kidney stones, symptoms of inflammatory bowel disease such as diarrhea, indigestion or bloody stool, metabolic problems, poor blood sugar balance, morning sickness and varicose veins.
- Infants and newborn babies more prone to vitamin K2 deficiency as their digestive systems lack the ability to produce.
- The drugs which halt Vitamin K2 absorption are blood thinners, antacids, aspirin, antibiotics, seizure medication, cancer treatment drugs and high cholesterol drugs, osteoporosis drugs and cholesterol lowering statin drugs.
Side effects
Excessive use of Vitamin K2 causes side effects such as low appetite, reduction in movement or activity, difficulty in breathing, enlarged liver, body swelling, irritability, muscle stiffness, yellow eyes or skin.
References:
https://www.healthline.com/nutrition/vitamin-k2#dental-health
https://en.wikipedia.org/wiki/Vitamin_K2
https://www.tabletwise.com/medicine/vitamin-k2-7
https://www.algaecal.com/algaecal-ingredients/vitamin-k2/