But although the language and meaning of flowers have their roots in the ancient past, they've evolved somewhat over the years. The first rule of giving flowers to your spouse is to know and give them what they personally like. That's more important than anything else.
How much vitamin D should adults take? According to the National Institutes of Health (NIH), the daily Adequate Intake (AI) for adults is 5 mcg (200 IU) daily for males, female, and pregnant/lactating women under the age of 50. People 50 to 70 years old should get 10 mcg daily (400 IU) daily, and those over 70 should get 15 mcg daily (600 IU). Based on recent research, Dr. Weil recommends 2,000 IU of vitamin D per day. Look for supplements that provide D3 (cholecalciferol) rather than D2 (ergocalciferol).
I take 3,000 IU daily, but I skip it in the summer. I feel markedly better after I've taken about 1,000 IU consistently for over a week. Tolerable upper intake limit (that is, max to safely take every day) is listed on wikipedia at 4,000 IU for adults. Wikipedia tells me that Vitamin D is fat-soluble, not water-soluble.