Hoodia

Hoodia gordonii

ApocynaceaeKalahari Desert: Botswana, Namibia, South Africa (Northern Cape, Western Cape); Angola; semi-arid to arid desert scrub

Description

overall appearance

A slow-growing succulent shrub reaching 0.5–1.5 m in height with multiple erect, cylindrical, cactus-like stems covered in prominent spines. Despite resembling a cactus, it is a true succulent dicot in the milkweed family. Growth is extremely slow; plants take 5–7 years to first flower.

roots

Fibrous root system adapted for rapid water absorption in desert rains; not used medicinally

stem

Erect, cylindrical stems 10–15 cm in diameter; green to grayish-green; covered in rows of conical tubercles tipped with sharp, pale spines 3–5 mm long; stems are the primary food/medicinal part

leaves

Reduced to small, scale-like rudiments at the base of spines; not functional

flowers

Large, dish-shaped, pale to deep pink or brownish-pink, 4–6 cm across; 5-lobed; with a strong, unpleasant rotting-flesh smell that attracts blowfly pollinators; blooms during hot dry season

fruits/seeds

Twin, slender, horn-shaped follicles 15–20 cm long; splitting to release seeds bearing silky tufts for wind dispersal

Active Compounds

P57AS3 (oxypregnane steroidal glycoside) — claimed appetite-suppressing compound patented by CSIRGordonoside F and related oxypregnane glycosidesCalogenin and related pregnane steroidal aglyconesHoodigogenin A (steroidal saponin)Luteolin and other flavone glycosidesTerpene esters and wax esters in stem cuticleCitric acid, malic acid (organic acids contributing to tart taste)Pregnane glycosides (multiple, structurally characterized in 2010–2015)

Traditional Uses

San Bushmen (primary traditional users): stems chewed during long hunts and migrations to suppress hunger and thirst; one of the most well-documented food-use ethnobotanical records
San practice: travelers and hunters on extended journeys through the Kalahari carried dried Hoodia stems
Khoikhoi pastoral use: eating stems to endure long drives with livestock across arid regions
Treatment of minor infections and digestive problems in San traditional medicine
Use as a bitter digestive tonic in San and Khoikhoi medicine

Modern Applications

Appetite suppression: P57AS3 glycoside hypothesized to act on hypothalamic appetite centers (VMH) by mimicking glucose-induced satiety signals — evidence primarily preclinical
Weight management supplement: most commercially sold for weight loss, but human RCT evidence is weak and inconsistent
One human RCT (2011, Phytomedicine): 1,100 mg/day purified P57-enriched extract over 15 days showed reduced caloric intake vs. placebo in obese women
Glucostatic hypothesis: steroidal glycosides may act on ATP-sensitive potassium channels in hypothalamus to reduce hunger signaling
Antidiabetic research: modest glycemic effects in preliminary animal studies
Hydration management: traditional claims of anti-thirst activity; not mechanistically established
Anti-inflammatory: in vitro activity against COX-2 and PGE2 production

⚠️ Safety Information

Contraindications

Diabetes: may mask hypoglycemic symptoms by suppressing hunger signals
Eating disorders: appetite suppression contraindicated in anorexia nervosa
Pregnancy and lactation: steroidal glycosides and unknown safety profile
Cardiovascular disease: steroidal compounds may affect cardiac electrophysiology
Liver or kidney disease: metabolism of steroidal glycosides not well characterized

Side Effects

Nausea, vomiting, and skin sensations (noted in one clinical trial)
Rapid heart rate and elevated blood pressure (reported in clinical studies)
Severe hypoglycemia risk in diabetic patients not monitoring glucose
Headache and dizziness

Drug Interactions

Antidiabetic medications (insulin, sulfonylureas): appetite suppression and glucose effects may cause severe hypoglycemia
Appetite stimulants (megestrol, cyproheptadine): opposing pharmacological effects
Stimulant medications (amphetamines, phentermine): additive appetite-suppressing and cardiovascular effects
Monoamine oxidase inhibitors (MAOIs): possible interactions via central satiety mechanisms