How much Vit D should you take a day?
Vitamin D recommended intake is at 400–800 IU/day or 10–20 micrograms. However, some studies suggest that a higher daily intake of 1,000–4,000 IU (25–100 micrograms) is needed to maintain optimal blood levels.
Does taking multivitamins really help?
The researchers concluded that multivitamins don't reduce the risk for heart disease, cancer, cognitive decline (such as memory loss and slowed-down thinking) or an early death. They also noted that in prior studies, vitamin E and beta-carotene supplements appear to be harmful, especially at high doses.
Are personalized supplements worth it?
They're unregulated: Customized or not, the supplement industry is largely unregulated, so there's no way to know what you're getting. Plus, there's no scientific evidence to suggest they're better than any other supplement on the shelf.