The amount of consumption of any particular substance differs, and the case is no different with kefir. For some people whose bodies are not used to probiotics or any other fermented foods, it is suggested that they start with a small amount of kefir a day and gradually increase as their bodies adapt to the homemade kefir. Since their bodies are not familiar with kefir, some might report cases of diarrhea. The older people get, the weaker their bones become. This can lead to bone fractures and osteoporosis. This is most common in women who are past menopause. Drinking about 3-4 cups of homemade kefir a day can help with strengthening bones as traditional homemade kefir, which is made from cow’s milk mostly and contains vitamin k, and calcium, both really important for the health of bones.