Herb library · Herb · Polygonatum odoratum
Solomon's seal
The knotted white rhizome of a woodland lily with arching stems and hanging bell flowers, used in European herbalism for bruises and sprains and in Chinese medicine as a nourishing food-herb. One placebo-controlled trial in older adults found changes in immune cells and gut bacteria, but no health outcome was shown.
Traditional use
Culpeper in 17th-century England recorded the bruised root applied to wounds, bruises and broken bones and taken in wine for ruptures. In Chinese medicine Polygonatum odoratum (yu zhu) is widely used in caring for older people, described as moistening the lungs and nourishing.
What studies show
- Limited· a lab measure, not a health outcome
Immune aging: in a randomized, double-blind, placebo-controlled trial of 140 independently living adults aged 60 and over, 90 days of P. odoratum lowered the share of certain aged T cells in the blood and shifted gut bacteria (more Akkermansia, less Klebsiella). The authors linked these changes to fewer respiratory infections only by correlation.
- Insufficient
Sleep: a 2019 placebo-controlled trial in 80 adults with mild insomnia found better sleep scores with an extract of a related species, P. sibiricum (huang jing). That species is not the one sold here, so it does not show what P. odoratum does.
- Insufficient
Bruises, sprains and joints: no studies in people were found.
Be careful of
Cautions
- NoteSolomon's seal poisoning in a dog was reported in 1983. Keep the garden plant, including its berries, away from pets and children, and use only the prepared rhizome sold as the herb.
- InteractionRelatives in the genus lower blood sugar in animal studies. If you take diabetes medicines, watch for low readings and tell your clinician.
- PregnancyNo safety information for pregnancy or breastfeeding was found in the sources used here.
- Ask a clinicianTalk with a clinician or pharmacist before using this if you take prescription medicines, are pregnant or breastfeeding, or are giving it to a child.
From the old books
What herbals and dispensaries of the past printed. History, in their words.
“The root of Solomon's Seal is found by experience to be available in wounds, hurts, and outward sores, to heal and close up the lips of those that are green, and to dry up and restrain the flux of humours to those that are old.”
Sources
- Associations between gut microbiota and immune profiles in community-dwelling older adults and the regulatory role of Polygonatum odoratum (Aging Cell, 2026) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
- Efficacy of Polygonatum sibiricum on mild insomnia: a randomized placebo-controlled trial (Nutrients, 2019) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
- Hypoglycemic activity of polygonati rhizoma in normal and diabetic mice (1993) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
- Solomon's seal poisoning in a dog (1983) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
Reviewed September 25, 2026.