"Natural" supplements may not be as beneficial as advertised, specifically with regard to healthful benefit if taken in massive doses, and worse, so-claimed "natural" sources, such as "plant-based." In fact, it is well known, now, if not known as well known even 20 - 30 years ago, that massive doses of Vitamin C may be not just necessary, but even harmful, if taken in excess. Vit. C is not alone in that risk. There are many vitamins and minerals and other supplement "natural" products that are harmful to ideal health if taken in excess.
And, the fact is, if a diet is based upon fresh food, with little to no processed food sources - essential, food purchased on the perimeter of your grocery store, conveniently, or grown yourself, that diet will suffice without the need of supplements, which can, in some cases, be ridiculously expensive and nowhere near the limited benefit derived since it is mostly not absorbed in the body, but passed through and discarded. Do you really need to dump money down the crapper? Need vitamin C? - eat fruit. Have we forgotten, or never learned the real sources of the nutrients we require? Didn't mommy ever teach you? Mine did, thank God.