Long COVID can affect the body in multiple ways, so boosting overall health and functioning may be more helpful than focusing on just one or a few symptoms. Several nutritional supplements are currently being studied as possible treatments for people with Long COVID, including L-arginine. L-arginine is an amino acid needed to create protein in the body, which helps build muscle tissue and support the immune system. It also helps regulate blood pressure and promotes cardiovascular (heart) health. L-arginine can be found in high-protein foods such as fish, eggs, and lentils and is also available as an over-the-counter vitamin supplement often combined with vitamin C.
Normally, the body is able to naturally produce all of the L-arginine that it needs. However, certain infections have been shown to reduce the amount of L-arginine produced by the body, something that has been found in people hospitalized for COVID-19. Since it is possible that L-arginine deficiency is linked to Long COVID symptoms, researchers studied whether an L-arginine supplement would help improve the overall health and vitality of people with Long COVID.
In a recent study by Tosato and colleagues, 50 people with Long COVID were assigned to take either an L-arginine + vitamin C supplement or a placebo (a sugar or dummy pill), similar to those found in over-the-counter supplements. Researchers measured participants’ handgrip strength, the health of their veins and arteries, how far they were able to walk in six minutes, and their level of fatigue at two time points: at the beginning and end of the study.
After 28 days of treatment, the researchers found that people taking the L-arginine + vitamin C supplement had greater improvements than the placebo group on every measure. Additionally, those who took the supplement had normal levels of L-Arginine in their blood – suggesting that taking the supplement helped to restore them back to healthy levels. Moreover, those taking the supplement did not report any serious side effects.
While this is an exciting finding, the researchers also caution that their study was small and conducted at only one medical center. Larger and longer studies will be needed to determine if L-arginine supplements can lead to long-lasting improvements among those suffering from Long COVID.
Even though L-arginine is currently available as an over-the-counter vitamin supplement, talk to your doctor first if you are interested in trying it, as there may be possible interactions with other medications you are taking or other health conditions you have.
Source: Tosato, M., Calvani, R., Picca, A., Ciciarello, F., Galluzzo, V., Coelho-Júnior, H. J., Di Giorgio, A., Di Mario, C., Gervasoni, J., Gremese, E., Leone, P. M., Nesci, A., Paglionico, A. M., Santoliquido, A., Santoro, L., Santucci, L., Tolusso, B., Urbani, A., Marini, F., Marzetti, E., … Gemelli against COVID-19 Post-Acute Care Team (2022). Effects of l-Arginine Plus Vitamin C Supplementation on Physical Performance, Endothelial Function, and Persistent Fatigue in Adults with Long COVID: A Single-Blind Randomized Controlled Trial. Nutrients, 14(23), 4984. https://doi.org/10.3390/nu14234984
