Vitamin C does not directly stimulate or modulate the immune system. It's effect is more indirect. Anything your body needs to function will improve immune system response along with everything else your body does. There are those who believe Vitamin C helps reduce the duration and intensity of colds and other ailments, but I don't think this has ever been proven but there is a ton of anecdotal and small studies that aren't double blinded that suggest it helps with this. But Vitamin C is mainly one of the body's most powerful antioxidants, and as this prevents degradation of a lot of essential nutrients and substances, in that way it obviously is necessary for health. It's not true that all liposomal C is in such high doses, and you don't necessarily want Vitamin C "on steroids." For one thing, vitamin C goes away when you urinate, it's not fat soluble, so you're only going to be able to use what the body determines is needed and the rest is expensive toilet water. It is strongest when taken intravenously, but you obviously can't do that yourself, and I don't see how it would help with withdrawal from anything. The best way to minimize withdrawal from any drug is to not take the drug on a regular basis and then you don't have a problem. But if you're using it daily or a lot of the time and for an extended period of time, then you can get the same awful withdrawals from stopping kratom as you can from stopping addictive drugs or antidepressants so to minimize this you need to taper off of it slowly as long as you need to in order to safely stop taking it. There is some research, very very small studies and only a couple of them, that indicate liposomal C is absorbed better than other forms in capsules but not a whole lot better than C not in capsules (powder form). But it does seem to minimize the downsides of taking C, which can be stomach problems. You can avoid those though usually be taking buffered C (ascorbate form) with a meal. But the one reliable study I found was on NIH, and it said that while they did find more of it circulating in the blood vessels, they weren't going to do the gold standard for C and take tissue samples and see if it was better where it needed to be better. So I guess that means we really don't know if it leads to better outcomes, only that it does seem to be better absorbed than the ways most of us take our C as a supplement. Of course, the best way to absorb it is in food, but you can't use food to take super high amounts of it which is what you're trying to do. And if you're just supplementing your food and not trying for some super unproven benefit of it doesn't matter that much if you absorb somewhat less of it. It's also more like taking a drug, as natural vitamin C isn't stuck inside a fat globule. It's a pharmaceutical product. But then, so is buffered C, although that is just trying to make it more like what it's like in food as you're eating and when you eat the food cuts down on the acidic effect of taking C, which is an acid. But again, tapering as slowly as needed when you quit is still the way to try to not have really bad lengthy withdrawals, though it doesn't always work, and I again don't see how any antioxidant is going to help with this.