We have a question on the safety of alkaline water. The recipe for this water comes from a health site (mix water with baking soda), and it is presented as a health product, not a tasty culinary product. We do handle food safety, and accept questions of the type "Is X safe?". Should we accept such questions also in the case where the "food" to be consumed is actually a preparation primarily supposed to enhance health?
Question like this one should be closed. Not only are they not about food preparation, answering them is dangerous/doesn't make sense.
We are not medical experts. We only apply a few well defined rules, created by informed authorities explicitly for the context of food preparation, to the situations presented by the people who come to us. Their purpose is simply to ensure that people get no foodborne infections from a batch of food. They are completely inadequate to account for other possible consequences.
Assume that the alkaline water has a long-term negative health effect when consumed regularly, but drinking a glass of it doesn't create food poisoning. By our rules, we cannot discuss the long term effect, and all answers will have to be reduced to "it is safe". Then people from all around the Internet will come and see this, and conclude that a habit of drinking alkaline water is harmless. We will be seriously misleading them.
People are already mislead somewhat by our current policy, because they have very different (and unrealistic) expectations of food safety than the strict definition. But I guess we can allow this for the purposes of meat left out on the counter and similar, because, for cultural and language reasons, their concept of "safety" in these cases is at least roughly aligned with the official meaning. With substances taken for medical purposes, "is it safe" does not default to "is it safe by food handling rules", and the idea of this interpretation is so unusual that people would keep not understanding it even if we were to shout it in their faces.
My second point is that this is not about food preparation anyway, and we have always been about food preparation only, excluding even potentially benign topics like serving food, or preparation of treats for pets. I don't see why we should allow a contentious topic like preparation of homemade "medicine".
Sure, there is a grey zone somewhere, but I think we can just go by feeling for what constitutes "food" traditionally. If somebody asks "is my smoothie safe to prepare in the morning and drink in the evening" and points to a recipe from a site which declares "drink a strawberry smoothie daily and you'll never get Alzheimer", I think we can declare the strawberry smoothie for food and answer it from a food safety point of view (while pointing out that we cannot say anything about the effect of the delay on potential anti Alzheimer properties). But the more it goes into an area where the OP seems to be interested in long term side effects, the more we should consider closing.