Do the natural products providing therapeutic benefit for the many health problems truly offering a cure or only symptomatic relief?

It is the resolution of symptoms that is the hallmark of a cure. There are, in fact, cases where a disease process continues in the absence of symptoms because there has been a change in the diet for a more optimal intake of certain natural foodstuffs that have medicinal qualities. So this then becomes, as much as anything, a semantic distinction as to whether they have been cured or are simply masking the condition. As you know, most physical health issues are karmic in nature and the karma cannot be cured using natural products. The supplements can only mask symptoms and this will likely not be a permanent solution on its own but can be a powerful way to manage things and make them essentially a non-problem in the most favorable cases, so this approach does have value and is worth looking into.