Brain tumor research is a relatively modern science that parallels the explosion of molecular biology and modern neuroimaging. While the science is new, Mayo Clinic has a long history of brain cancer treatment and research stretching back over 100 years.
But not all vitamins are water-soluble, and the ones that are lipid-soluble, meaning they like to hang around in your body's fat, don't get flushed out. Instead, if you take too much of a lipid-soluble vitamin over a few weeks to a month, they sit in the liver and can build up to toxic levels, causing problems ranging from weak bones to liver damage, according to Katherine Zeratsky, a registered dietician nutritionist at the Mayo Clinic.
Keep in mind, though, that many diet supplements have vitamin D, so before you take another one, check the labels and let your doctor know what youâre taking. Getting too much vitamin D, especially above 4,000 IU per day, can be dangerous. If you already have osteoporosis, keep in mind that vitamin D and calcium alone are not enough to treat the disease. Youâll need to take them along with other medications your doctor prescribes.