Corny, I don't know how you feel about Vitamins, I used to think they were just worthless, and billions were spent by clueless people. I finally gave in, and sat down and spent numerous hrs doing some research on my own, most of my research was done on vitamin D3, because in my research the effects of it caught my biggest skeptical attention. Long story short, I saw were a "Doctor" and his wife had been taking 5,000 IU of Vitamin D3 for like 20 years and had never been sick, I chuckled but I said, this stuff is cheap, so I will buy me some of the most quality ones I can find online and check it out. I have been taking the 5000 IU a day for about a little over a month now and everyone one in my family has the crud bad, I mean bed ridden bad, kids...grand kids...son in law...etc and I have been around all of them during the Holidays. I did get a very, very mild case of what they had, lasted about 2 days, and was mostly just a few sniffles, but nothing at all like the way they suffered, not even close, today I feel good, and they all are doing a lot better but still in the recovery mode. The Government recommended dose is 100 to 300 IU's a day "of course" they don't want us well that's not good for all the Doc's and big pharma, but I am living proof that something is happening in my body, that is doing something, I use to could just look at someone with a cold and get the crud. If you are a skeptic on vitamins, just do a little research on D3, and they also have a few awesome YouTube videos that will blow your mind. Today I take just a regular Multivitamin like Centrum along with my 5000 IU of D3 everyday, that's all, not no handful of many different ones, just two. I have never felt better in my life, and could kick myself for being so stubborn, I don't know how what I am doing will effect anyone else, I can only tell you what these two vitamins have done for me, I call it at the very least a miracle.