Vitamin K2

Keeps calcium in your bones and out of your arteries

Vitamin K2 is an oily yellow vitamin called menaquinone and is made by bacteria in our intestines from cheese and eggs, or by converting K1 its sister vitamin.

Vitamin K2 controls the calcium in our body and retains it in our bones where it belongs. Otherwise calcium can build up in our artery linings and harden them, causing atherosclerosis. It can also harden heart valves. So vitamin K2 helps prevent hardening of our arteries, also heart valve problems (which are surprisingly common) and bone weakness (osteoporosis).

The recommended daily need of K2 is set at 60 mcg for women and 75 mcg for men, but most people do not make anywhere near this much. In 2004 the Rotterdam Study found that persons whose bodies made even 45 mcg of K2 daily, lived seven years longer than those who made only 12 mcg daily.

Dr Cees Vermeer of Germany, one of the world’s top vitamin K researchers, reports that men with the highest amounts of K2 in their blood have around 50% fewer heart attacks than normal. This is because of K2’s effect of keeping calcium in the bones and preventing it from being deposited in the arteries and hardening them and damaging heart valves. Dr Vermeer recommends at least 45 mcg daily of vitamin K2, up to an optimum amount of around 185 mcg.

With regard to K2 and bone health, a Japanese study of 60 older women, 36 without spinal fractures and 24 with fractures, found that the average blood level of vitamin K2 in the non-fracture group was twice as high as for those in the fractured group. Again this is because the body’s calcium is retained in the bones, helping to keep them dense and strong.

A rich, ready-made source of vitamin K2 is a fermented Japanese food called Natto. Natto is made from fermented soybeans. Japanese love it, but foreigners tend to loathe it (rather like the reaction of Americans to New Zealand Marmite). Natto contains ready-made K2 (ie, it does not need to be converted by intestinal bacteria). Natural K2 supplements are made from Natto.