**6. Conclusions**

Much of the evidence (both scientific and anecdotal) presented for the health benefits of amended, modified, or specialty waters is based on one of several types of inquiries. The first includes animal studies and in vitro laboratory investigations that are valuable and represent an essential step in researching health effects, but alone are not definitive. Another is the study of people whose drinking water has one or more of the specified attributes and who appear to be either healthier or longer-lived than most others. These studies frequently represent small or regional populations that are geographically and/or socially isolated and, thus, may possess diets and lifestyles that differ appreciably from those of most postmodern populations.

Another line of evidence for the reported benefits of ingesting modified or specialty waters pertains to the treatment of specific diseases or chronic health problems. Fewer research studies have focused on whether, or how, these waters may improve or sustain wellness among relatively healthy people and, therefore, the routine or prolonged consumption of some modified or specialty waters has been questioned. Additionally, at least some of the hypothesized health benefits are based on product-sponsored research, which may be legitimate but would benefit from corroborating studies by funders who have no financial stake in the findings. Finally, anecdotal observations and customer testimonials can be quite useful, but are not definitive, in evaluating actual health benefits.

Nonetheless, results from all of the aforementioned types of investigations and observations collectively sugges<sup>t</sup> that water's quality is not limited to its simply being free of contaminants. Whereas accepted scientific mechanisms for the efficacy of some of the purported health benefits of water modifications or additives do not currently exist, it does not mean that such benefits are without merit. Research into human nutrition has revealed unexpected, but generally accepted, influences on processes ranging from gene expression to brain plasticity for which the mechanisms are not ye<sup>t</sup> fully understood.

Research studies that investigate both the health effects of modified or amended alternative waters, and mechanisms for their doing so, would be valuable in evaluating whether relatively healthy people might benefit from routinely drinking them. Research into the health benefits of high-quality natural waters [26], which could serve as a model for amending alternative waters, may also be a productive endeavor. Given the likelihood that alternative drinking waters (e.g., recycled, desalinated, atmospheric, cloud captured) will be increasingly consumed as a result of the ongoing depletion and pollution of traditional surface and ground water sources, it would seemingly be worthwhile to better understand how these alternative waters could be optimally modified to improve taste and to potentially promote human health.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable. **Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The author declares no conflict of interest.
