Vitamin K2 Benefits. The main thing vitamin K2 does is control where calcium does-and doesn`t-go in our bodies. That is, it should go into our bones and blood, but not arteries or muscles.Without it, we can end up with bone spurs, hardening of the arteries and age-related brain diseases like Alzheimer`s disease.pecifically, research has found that vitamin K2 benefits include protecting nerve cells from oxidative stress and possibly reducing neuronal damage (slowing progression of dementia.) Vitamin K2 benefits were also found to reduce liver cancer in women and prostate cancer in men.