Is it safe to take multiple daily vitamin supplements?

What For? For what purpose are you doing so? It may not be wise to take them once a day, let alone multiple times. If you have a known deficiency in a vitamin, try to address the deficiency from whole foods and for vitamin d, from the sun. See this website. http://ods.od.nih.gov/factsheets/list-all/ otherwise, only take what you need. More is not better.
No. There is such a thing as hypervitaminosis (e.g. Vitamin a is teratogenic in excess for reproductive age women) and you are advised to not take multiple daily vitamin supplements. In addition, vitamin supplements have few proven benefits and cost a lot of money. Spend that money on a healthier diet instead.

Related Questions

5mths postpartum, exclusively breastfeeding, is it safe to take vitamin supplements such as Vitamin E and Fish Oil?

Fish oil ok; ? Vit E. Nutrition requirements for breast-feeding mothers are similar to those during pregnancy. Special attention to intake of protein, calcium, iron and vitamin C is advised. Fish oil supplements are likely safer than eater fish because of toxins found in some fish, but too much could increase risk of bleeding. Evidence about the safety of higher doses of vitamin E is inconclusive, so not recommended. Read more...

What vitamins and supplements are safe or good to take to improve health after a diagnosis of atypical lobular hyperplasia?

Expect little help. You're welcome to supplement with a cheap multivitamin-and-mineral tablet; i think this is a good idea, but no supplement i know is going to be helpful in dealing with the atypical lobular hyperplasia. Instead, simply keep up the vigilance your physicians have recommended, and should you have progression to cancer, you are most likely to get a cure. Good luck. Read more...