Researchers have identified medicinal herbs traditionally used to treat viral respiratory infections that may, as indicated by computer modelling, help with COVID-19. While this is very early work, given that plants and herbs are involved there’s little downside but potentially large benefits in the current situation.
The paper also provides a table of 26 herbs that contain two or three of these 13 compounds. Six of these herbs have been trialled against the related illness SARS (also caused by a type of coronavirus) and Swine Flu (H1N1).
Combined with immune boosting foods, the foods and herbs below may give an edge in either not catching or limiting the severity of the disease.
Lignan. Lignans are found quite widely in plants foods. The standout source is flaxseed (also known as linseed) but is also found in sesame seeds, pumpkin seeds, cashews, peanuts, whole grains, Brassica vegetables (kale, broccoli, cabbage etc), carrots, red and green peppers, and various fruits.
Moupinamide. The main food source of this is bell peppers, particularly when riper (red and yellow).
Betulinic acid. This isn’t easily found in common foods but may be present in the herb rosemary.
Cryptotanshinone. This is found in the Chinese herb Dan-Shen (also known as red sage, tan-shen). It is found in various other Salvias so the herb sage may be a source. Another compound identified (dihydrotanshinone) is also found in Dan-Shen.
Quercetin. This compound is widely available with some good common sources being coriander (cilantro), kale and broccoli, onions, apples, berries and black tea.
Kaempferol. Another quite widely available flavanoid. Good common sources include kale and arugula (rocket).
N-cis-feruloyltyramine. As with moupinamide, the main food source is bell peppers, particularly red and yellow.
Other compounds identified in the study (desmethoxyreserpine, sugiol, tanshinone IIa, dihomo-γ-linolenic acid, & coumaroyltyramine) don’t seem to be available from common foods or herbs.
Reference: Zhang D, Wu K, Zhang X, Deng S, Peng B. 2020. In silico screening of Chinese herbal medicines with the potential to directly inhibit 2019 novel coronavirus. Journal of Integrative Medicine 18:152–158.