General Description
Alfalfa (also known as lucerne or purple medic) is a perennial legume of the pea family, native to western Asia and the eastern Mediterranean region and cultivated throughout much of Europe, North America, and South America. The plant has an erect stem growing 40 to 90 centimeters tall, and grayish-green, clover-like leaves. Alfalfa flowers throughout much of the summer, bearing clusters of small, blue or purple flowers, which produce coiled pods containing multiple seeds. Perhaps the most remarkable attribute of alfalfa is its extremely deep root system, which may reach depths as great as 15 meters in porous subsoil. After just five months of growth, the tap root may reach as deep as two meters. Cultivated primarily for hay and silage, alfalfa has a remarkable capacity for rapid regeneration of stems and leaves after cutting, allowing several crops of hay in one growing season.

Health Applications

• General nutrition
• High cholesterol
• Diabetes

History and Traditional Use
Alfalfa is believed to have originated near Iran, but it has been naturalized thoughout much of the world. As early as 490 B.C., Roman writers described alfalfa's value as feed for horses and other animals,¹ and it remains an important component in the diets of dairy cattle, horses, beef cattle, sheep, and goats. Alfalfa is the oldest cultivated forage crop in the US, introduced into eastern North America by colonists in 1736.¹ The leaves and seeds of the plant have been used for a variety of medicinal purposes ranging from diabetes, poor appetite, urinary and bowel problems, water retention, and arthritic complaints.^2,3 However, there is little scientific evidence to support these traditional applications. Chemical Composition
A rich source of protein, fiber, and vitamin K, alfalfa also contains carotenoids (especially lutein), saponins, isoflavonoids (including glycosides, genistein, and diadzein), triterpenes, coumarins, glycosides, fatty acids, and betaine.⁴

Diabetes/High Cholesterol
While the effects of alfalfa on animals have been studied extensively, very few studies have examined the herb's effects on humans. Most studies on the medicinal properties of alfalfa have centered on its purported cholesterol-lowering and antidiabetic properties. Studies conducted on diabetic-induced mice indicate that compounds in alfalfa may help stimulate insulin secretion and lower blood sugar levels.^5,6 Alfalfa saponins were found to inhibit cholesterol absorption in rats,⁷ and preliminary human studies indicate that alfalfa seeds may lower both total cholesterol and LDL (the "bad" cholesterol) levels.^8,9 However, no large-scale studies have been conducted to confirm these preliminary findings.

Dosage/Toxicity
No therapeutic dosage of alfalfa has been established for humans. Consumption of alfalfa leaves and seeds have not been associated with any toxicity. Alfalfa sprouts have induced symptoms of systemic lupus erythematosus (SLE) in lab experiments, apparently due to the action of L-canavanine, an amino acid found in alfalfa seeds and sprouts. In vitro studies indicate that L-canavanine influences the activity of immunoregulatory cells, which may account for lupus-inducing activity.¹⁰ Consequently, many herbalists recommend that people with SLE avoid alfalfa products. In recent years, consumption of fresh alfalfa sprouts, a popular ingredient in salads and sandwiches, has been associated with outbreaks of Salmonella and E. coli infections. Until effective measures are found to prevent sprout-associated disease, people who wish to reduce their risk for food-born illnesses (in particular, the elderly, children, people with compromised immune systems, and others at risk for severe complications of E. coli or salmonella infection) should not eat raw sprouts.¹¹