Take home message:

• It is advisable to consume fermented milk products regularly. Our intestinal microflora, regularly needs probiotic and prebiotic supplementation for optimal functioning.
• Vitamin K2 is produced during milk fermentation and the intake of K2 is supportive for cardiovascular health and reduced risk for the metabolic syndrome.

Fermented milk in human studies

Fermentation makes milk different from fresh milk. An observational retrospective study indicated that Swedish women suffered fewer strokes or were less likely to develop osteoporosis, if they had regularly consumed fermented milk products such as yogurt, Swedish acidified milk or cheese (Michaelsson et al. 2014). The normal pasteurized milk, however, was associated with increased mortality, cardiovascular disease and osteoporosis. In another study (Beltran et al., 2018), people drank 150 ml of fermented pasteurized milk per day that was fermented with a strain of Lactococcus lactis (NRRK B-50571). The control group received pasteurized milk acidified with lactic acid without bacteria. This was a double-blinded experiment where neither the test people or the study managers knew what the people were drinking. At the start of the experiment, the participants had a slightly elevated blood pressure (average 134/88). After 8 weeks some interesting changes could be noticed:

• The hypertension only decreased significantly in the Lactococcus lactis
• After the end of the trial, the blood pressure rose again, indicating that these products should be consumed regularly for blood pressure reduction.
• After the eight week trial, both cholesterol and triglyceride levels showed a slight decreasing tendency in the Lactococcus lactis consumers.

The underlying mechanisms for these changes need to be further determined. Some strains of Lactococcus produce large amounts of the vitamin K2 and fermented milk is generally high in vitamin K2. K2 regulates the calcium deposition in the body’s bones. This may lower calcium deposition in the blood vessels resulting in smoother vessels remain, which may lower blood pressure. Gast et al. (2008) performed a prospective study with healthy women without cardiovascular diseases and they noted reduced risk of cardiovascular diseases (CVD) with higher consumption of vitamin K2. There was a risk reduction (or odds ratio) of 0.91, which implieds that for every increase of 10 mg K2/day, the risk for CVD decreased by 9%. Most of the vitamin K2 was in the form of MK7, MK8 and MK9 (Vitamin K2 = menaquinone = MK) from dairy products. It is noteworthy that such a CVD risk reduction was not found with the intake of vitamin K1 (K1 or phyloquinone from green plants, like kale). Similar results have been observed with vitamin K2 intake and reduced risks of the “metabolic syndrome” (including obesity, diabetes, etc.). Vitamin K2 has been linked to decreasd blood triglycerides and waist circumference (which is an important indicator of the “metabolic syndrome”). Similarly, as for CVD, no risk reductions were noted for vitamin K1.

Pre- and probiotics in gut health

In this millennium there is more attention on the indirect effect of our food (through intestinal gut flora changes) instead of the direct effect (nutrient supply). In the case of various civilization diseases (like allergy, obesity, diabetes), the axis between the intestine and the brain or the intestine and the hearth has already been discovered. A well-functioning gut microflora can reduce various health problems. The question arises how one can positively modify the intestinal microbiome. One can take organic soil fertility as an example. In the philosophy of organic agriculture the plant is not been nourished directly (with water-soluble fertilizers), but indirectly via the soil life. Therefore, the word “living soil” is used. Just as soil life is there for the plant, the intestinal microflora feeds the animal- or human organism. Probiotic means “for life” or, in other words, “supporting life”. Lactococci, bifidobacteria and various other bacteria play a crucial role. Prebiotics are ingredients which feed probiotic microorganisms to support the host health. Prebiotics feeding the probiotic bacteria include oligosaccharides in milk (small milk sugar molecules). Pre- and probiotics as part of a healthy soil and a healthy gut.

Photo: Blue cheese contains a lot of vitamin K2