evidence: An image containing the claim that eating alkaline foods can "defeat" SARS-CoV-2, the virus that causes COVID-19, has been shared at least 800,000 times on Facebook since early April 2020. This claim is incorrect and displays a fundamental misunderstanding of basic science principles. First, viruses do not have their own pH. Sarah Stanley, an associate professor of infectious diseases and vaccinology at the University of California, Berkeley, explained to The Associated Press that "pH is something that applies to a water-based solution, which a virus is not." [...] In summary, food at any pH will not alter the very tightly controlled pH of tissues targeted by SARS-CoV-2. Therefore, an alkaline diet will neither prevent nor treat SARS-CoV-2 infection.