Originally Answered: In biology, what is chiasmata? If you are asking for cell biology, âChiasmaâ is a point of overlap of paired chromatids at which fusion and exchange of genetic material take place during prophase of meiosis. It is the X-shaped structure formed at the point below the brain where the two optic nerves cross over each other.
However, a diet rich in fruit and vegetables that is typical of a vegan diet has a positive effect on the calcium economy and markers of bone metabolism in men and women (49). The high potassium and magnesium content of fruit and vegetables provides an alkaline ash, which inhibits bone resorption (53).
To get the full benefit of a vegan diet, vegans should do one of the following: 1  Eat fortified foods two or three times a day to get at least three micrograms (mcg or Âµg) of B12 a day or. 2  Take one B12 supplement daily providing at least 10 micrograms or. 3  Take a weekly B12 supplement providing at least 2000 micrograms.