**7. Vitamin K2 and a plant-based diet?**

poor prostate health is not a hormone issue, but a cardiovascular issue [51]. The first piece of evidence comes from interventional radiologists Dr. Gat and coworkers, who were initially working on reversing infertility in men by relieving varicoceles, or varicose veins in the pampiniform venous plexus. They discovered that varicose veins in the internal spermatic vein, which normally returns blood from the testes to the kidneys, prevented normal blood flow. The one-way valves had failed in this vein, possibly causing the varicose vein, or as part of the process of forming varicose veins—the exact mechanism is debated. So instead of normal blood flow, the blood flowed retrograde through the prostatic veins. When testosterone levels were measured near the prostate gland in 12 infertile men with varicocele, the mean concentration was 3632 pmol/l compared to 27.33 pmol/l in the serum, or about 130 times higher [52]. By occluding the internal spermatic vein, Dr. Gat was able to relieve the physical pressure due to the elevated blood pressure caused by the height of the column of blood sitting in the internal spermatic vein and also made a pathway through normal venous pathways for blood to drain away from the testes without retrograde flow past the prostate. This venous occlusion surgery led to relief of benign prostatic hyperplasia (BPH), and possibly prevention of prostate cancer

Varicose veins and destruction of the one-way valves in the internal spermatic vein were the direct cause of BPH, but what causes varicose veins? Work by Cario-Toumaniantz and coworkers [53] on the differentially expressed genes and gene products in varicose vein tissue showed an overexpression of genes involved in extracellular remodeling, including matrix Gla protein. Smooth muscle cells were seen proliferating in varicose vein tissue with high expression of MGP, particularly the uncarboxylated form of MGP. Overexpression of MGP and proliferation of smooth muscle cells have been seen before, reported by Price and coworkers investigating the effects of warfarin on arterial calcification in rats [15], and by Schurgers and coworkers reporting the reversal of warfarin-induced arterial calcification in rats [28]. In areas of calcification of arteries, there is proliferation of smooth muscle cells and increased expression of uncarboxylated MGP, similar to what was seen in varicose vein tissue [53]. It is likely then that vitamin K is involved in the mechanism by which varicose veins form, just as it has been implicated in the formation of arterial calcifications. When varicose vein tissue culture was treated with warfarin, mineralization increased, which could be inhibited by the inclusion of vitamin K in the culture media [53], indicating a direct role for vitamin K in the prevention of

In addition to this evidence from cellular biology, evidence from a prospective observational study showed an association between intake of vitamin K2 and poor prostate health manifested as prostate cancer. There was a significant association between menaquinone intake and advanced prostate cancer in the EPIC-Heidelberg cohort [54]. A nested case-control follow-up study also found an association between the ratio of undercarboxylated osteocalcin to carboxylated osteocalcin and high-grade prostate cancer and advanced prostate cancer [55]. Neither of these reports found a connection with vitamin K1 intake. Further evidence comes from a retrospective study of warfarin use and clinical stage of prostate cancer at diagnosis [56]. While some of the evidence for intermediate or short-term use of warfarin is conflicting, the comparison between those men who had used warfarin for at least 4 years in the 5 years

as well [52].

180 Vitamin K2 - Vital for Health and Wellbeing

varicose veins.

Reversal of atherosclerosis by a plant-based diet has already been mentioned in this chapter [27]. Dr. Esselstyn has also shown that a plant-based diet very low in fat can reverse coronary artery disease [57]. Of 198 subjects in the lifestyle intervention study, 177 were adherent to the program while 21 formed a control group of non-adherent comparison subjects. There was reversal of angiographic-verified blockages in 39 adherent subjects. Disease progression occurred in 4 (2.3%) adherent subjects, but in 11 (52.4%) of the non-adherent subjects. Coronary artery calcification was not measured.

There is abundant evidence that increased consumption of fruits and vegetables in conjunction with exercise and a healthy lifestyle is beneficial for cardiovascular health and lower cardiovascular mortality. Healthy diets have been reported to lower cardiovascular mortality risk by about 30–40% [14, 58, 59]. When combined with other lifestyle factors, the risk plummets to about 20% or less compared to the least healthy fraction of the population [60–63].

The point here is that all available resources should be used to counter the disease process and to promote healthy aging. While vitamin K2 is a valuable nutrient that is generally in short supply in the global diet, the context of the entire diet must be kept in mind. The best results will be obtained by a full complement of healthy foods. Population studies have shown that even 40–50 µg/day of menaquinones from the diet is associated with cardioprotection [6, 7] and lower risk of advanced prostate cancer and lung cancer [54, 55, 64].

Is vitamin K2 compatible with a plant-based diet? While most of the common sources of menaquinones are cheese, fermented dairy products, eggs, and meats, there are plant sources as well. While these are animal products, judicial selection could be used to maximize K2 intake without consuming a large amount of any animal-based foods. Natto is a well-known Japanese food that is very rich in MK-7, though not very popular outside of Japan. The menaquinone in natto is made by fermentation with *Bacillus subtilis var. natto*. Fermented vegetables such as sauerkraut contain a small amount of menaquinones as well. By selecting probiotic bacteria based on their production of menaquinones, the amount of vitamin K2 from a serving of fermented vegetables could be significant. More product development is needed in this area.
