Plant Profile: Red Clover
It’s not quite spring yet in my neck of the woods, but I’m already dreaming of a beloved Fabaceae (pea and bean) family friend. Red clover fits its botanical name, Trifolium pratense, which means three-leaved meadow dweller. Its pink-purple flowering tops are commonly spotted as a cover crop in agricultural communities as well as prolifically growing wild in meadows and fields across so-called North America. It is a perennial plant that is identified by its dense pink inflorescence clusters, trifoliate leaves, hollow and hair stems, and branchy taproots. It is used as food by many insects (including honeybees!) as well as by herbaceous mammals. It is a necessary part of its ecosystem, and offers support to humans as both food and herbal medicine.
Clinically, T. pratense is used primarily to support the respiratory, immune, integumentary (skin), generative (aka “reproductive”), and lymphatic systems. There is scientific research on its efficacy in addressing osteoporosis, fibroids, menopausal symptoms, premenstrual shifts, dyslipidemia, metabolic syndrome, and much more. It is highly anti-inflammatory and alterative, helping the body to clear waste materials from the lymphatic, integumentary, and circulatory systems. It is used clinically to address swollen lymph nodes and lymphedema alongside other alterative herbs such as burdock, yellow dock, and calendula. It can be used topically with plant friends like chamomile, comfrey, plantain, calendula, gotu kola, and lavender to address skin conditions such as eczema, psoriasis, and dermatitis. I think of T. pratense as a beautiful tea companion alongside hyssop, peppermint, elder, and yarrow as part of blend to support the respiratory system in conditions such as bronchitis, whooping cough, or whenever the respiratory tract is irritated and there is a spasmodic (hacking) cough.
Red clover is also used clinically to address sex-hormone-influenced conditions such uterine fibroids, hot flashes, and premenstrual syndrome. As I’ll discuss, there are contradictory and inconclusive findings as to the safety and efficacy of T. pratense for these purposes, despite its traditional indications.
Research on T. pratense attributes much of its medicinal power to the presence of a few key plant constituents: blood-thinning coumarins, phytoestrogenic isoflavones, antioxidant flavonoids, and necessary minerals such as iron, potassium, and magnesium. In particular, the isoflavones genistein, daidzein, formononetin, and biochanin A which are considered phytoestrogenic may play a role in T. pratense’s traditional and clinical applications for addressing estrogen-influenced conditions such as postmenopausal osteoporosis.
Some sources claim that T. pratense is unsafe for long-term use for people who are pregnant or lactating and for people diagnosed with or at-risk for estrogen-sensitive conditions (such as endometriosis and cancer of the breasts/chest, endometrium, and ovaries) due to phytoestrogenic activity. However, it is considered safe for short-term and culinary use for most people. Current findings are mixed and inconclusive on whether T. pratense also contains constituents which may be helpful in supporting the body to address estrogen-sensitive cancers. For example, a 2017 study suggests that T. pratense isoflavones have differential effects on estrogen metabolism in "normal" vs cancerous cells. A 2018 study found that a T. pratense component called irolone that may potentiate the effect of progesterone in both endometrial and ovarian cancer cell lines. In these cancers, progesterone action is generally associated with positive outcomes. Memorial Sloan Kettering Cancer Center advises not to take T. pratense if:
You are taking warfarin or other blood thinners, as coumarins in T. Pratense could increase risk of bleeding.
You have a hormone-sensitive condition such as estrogen receptor-positive breast cancer, ovarian cancer, endometriosis, due to T. pratense’s potential phytoestrogenic activity.
You are taking methotrexate, as abdominal pain and nausea may result from combining T. pratense with this medication.
Further research is warranted as to how T. pratense interacts with pharmaceuticals and influences the overall wellbeing for people with estrogen-dependent conditions. Until then, proceed with caution and consult with an herbalist and a doctor for more information.
These cautions notwithstanding, red clover is safe and well tolerated by many people (including children) as tasty springtime food. Kids and kids-at-heart will enjoy helping to forage for clover ripe buds. Its light, salty-sweet taste is a lovely culinary addition to springtime salads and soups as well as when ground into a flour and used in baking. T. pratense is rich in many vitamins and minerals and has been studied for its role in balancing blood cholesterol. It can also be used for making sweet treats like jelly, mead, cookies, and syrup! Check out these resources for more information on foraging edible plants:
Edible Wild Plants: A North American Field Guide to Over 200 Natural Foods by Thomas Elias and Peter Dykeman