It's hard to go wrong with anything from Douglas Labs. This is a good daily maintenance formula although even as a daily formula I feel like I need to take 2 of these just to get what I consider a minimum dose of Vitamin D especially. Normally I take between 2,000-5,000 IU's of Vitamin D per day and this one has 1,000 IU's per capsule.<br /><br />As a comparison, the Bluebonnet Nutrition Vitamin C, D3 & Zinc contains 2,000 IU's of Vitamin D per capsule and 50mg of zinc (more than 3X the amount in the Douglas Labs formula). And it is less than half the price. I still prefer Douglas Labs or Throne over Blue Bonnet, but if you are on a tighter budget I would recommend the Blue Bonnet as an alternative.<br /><br />This is still a good daily formula for most, but if you are like me you will probably want to take 2 capsules per day instead of one.<br /><br />Be careful though with taking high doses of zinc without copper as both should be kept in balance as much as possible. According to the Linus Pauling Institute, taking large quantities of zinc (50 mg/day or more) over a period of weeks can cause a copper deficiency. Livestrong recommends a ratio of 2 mg of copper to be consumed for every 15 mg of zinc. For example, if you take 30 mg of zinc for the day then 4 mg of copper is required to maintain a proper ratio (Formula = (Zinc amount 30 x 2) / 15 = 4.