Eating more acidic or alkaline foods is not related to an increased or decreased risk of COVID-19 infection. Widely circulated social media posts falsely suggest that the pH of COVID-19 ranges from 5.5 to 8.5. Often these posts advise readers to eat alkaline foods (specifically fruits and vegetables) with a pH of more than 8.5 to prevent COVID-19. Viruses themselves do not have pH levels, because they are not water-based solutions.
In chemistry, pH (power of hydrogen, or potential for hydrogen) is a scale used for water-based solutions to indicate if they are acidic (pH below 7, with a lower pH indicating a stronger acid), neutral (pH around 7), or basic (pH above 7, with a higher indicating a stronger base). Since viruses are not water-based, the pH scale does not apply to the novel coronavirus SARS-CoV-2, the disease that causes COVID-19.
While some illnesses or medications may cause blood pH levels to increase or decrease in our bodies, foods eaten as part of a regular diet do not have a significant impact on blood pH. Saliva and urine pH may change in response to diet, but these changes are variable from person to person and** will not prevent or cure COVID-19.**
The posts in question seem to consistently refer to a 1991 paper in which another type of coronavirus, the coronavirus mouse hepatitis type 4 (MHV4), was studied in mouse or rat cells in a solution with a pH of 5.5 to 8.5. Mice and rats are not the same as humans, and this study was not conducted in humans or on human cells. In addition, MHV4 is not the same as the SARS-Cov-2 virus that causes COVID-19, and this study was performed well before the SARS-Cov-2 was discovered in 2019.
Eating a well-balanced diet including a variety of fruits and vegetables can help support immune function which may help to prevent illness in general, but there is not enough evidence to suggest that a well-balanced diet would be effective in preventing or treating COVID-19.
In chemistry, alkaline is an adjective that is sometimes used to describe a subset of bases that dissolve in water. Alkalinity, however, is a different term used by oceanographers and hydrologists to describe the capacity of water to resist pH changes that would make it more acidic, in contrast to basicity which refers to a measurement on the pH scale above 7. When food is described as alkaline, this is often based on misconceptions about the impacts of eating food on the pH of the body. Fluids associated with various organs and tissues in the body have different typical pH levels; for example, the stomach operates at an acidic pH for digestion. Eating food does not have a significant impact on blood pH as this is regulated by the body to stay relatively neutral (pH of 7.35 to 7.45).
One popular social media post incorrectly applies a research study about another type of coronavirus called mouse hepatitis type 4 (MHV4), and also lists food items with pH values that are inaccurate. For example, lemons are falsely listed to have a pH of 9.9 (the true pH is closer to 2-2.6) and avocados with a pH of 15.6 (the true pH is likely 6.27-6.58). For reference, the pH scale only goes from 0 to 14, and food products are generally within a pH range of about 2 to 8. It is important to note that eating more alkaline food does not change the risk of COVID-19 infection or treat COVID-19.
We base our COVID-19 expert contextualizations on information provided by internationally-recognized health organizations, public health researchers and infectious disease experts. Because information in epidemics is constantly being updated, our content is up to date based on the date and time they are published. If you’re looking for medical advice, please contact a healthcare provider, and be sure to review the World Health Organization website for more information about COVID-19.