Dear Customer , This is Dr. S. Tomar from healthcaremagic.com s medical team and I ll be your medical advisor for this question. First of all thank you for sharing your concern with us and showing trust on us. As you are a natural bodybuilder so first I would like to appreciate it and requests you to be a natural bodybuilder in future as well . Your daily need of calcium is around 1300 mg . I would encourage you take your most of the portion from dairy products as now a days fat free dairy is easily available so you will not gain weight but will get your most of the calcium through it , but if you find that you are not having enough 1300 mg of calcium from your food products then can take 500 mg calcium citrate. Our bones are similar to muscles if you exercise bones become strong . I would encourage you to eat a well balanced healthy diet which will give you all necessary vitamins and minerals . There is no need to take any extra vitamins if you are on a balanced healthy natural diet which contains enough variety of vegetables , fruits , white meat , fish , sea food . This is my initial response and discussion is open until you have any query or need further clarification. I wish you good health . Thank you for your question and feel free to contact further for any question . sincerely, Dr. Shardendu Tomar