Don’t fall for nonsense, just because a product is found in nature does not mean it is good for you or is any better than man-made substances. When people mention that something is “natural” in order to make you more interested in it they conveniently want you to forget that there are a lot of natural substances that are potent enough to kill you hundreds of times over.
Also, remember that the danger is in the dose. Normally toxic substances can be harmless in small amounts and typically safe substances can be very toxic in large doses. We put toxic substances into our bodies every day and most people will never see the effects of them because they are in such small doses. This whole concept is why the EPA and other agencies can post acceptably safe levels of things such as mercury, arsenic, dioxins, etc. A “natural” product doesn’t necessarily have safe levels of ingredients
And while I’m on the subject, if you ever see a product that claims to “boost your immune system” run away from that product. What the hell does that statement even mean? First, the company that is promoting their product would have to show that it somehow modulates some part of the human immune system (increasing T-cells?). They would then have to show that the modulation their product induces actually has the desired effect on whatever problem/disease it is trying to alleviate/cure (because you can’t just assume that an increase in something in the immune system is actually going to change the immune system – a bit counter-intuitive, but that’s how science works).
Personally, I stick to well-known, tried-and-true drugs, and I think you should too.