Cissus quadrangularis, a grape-family vine sold as a dietary supplement for bone healing, joint comfort and weight control, presents a mixed picture. The strongest human evidence, on weight, blood fats and blood sugar, comes almost entirely from one group working with the extract's seller. Bone and joint evidence is weaker. Short-term use appears well tolerated; open questions are a rising calcium-controlling hormone and added blood-sugar lowering with diabetes medication. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Fasting glucose | 75–90 mg/dL | Detect hypoglycemia or benefit |
| HbA1c | 4.8–5.4% | 3-month glucose trend |
| Parathyroid hormone | 20–45 pg/mL | Key safety signal |
| Serum calcium | 9.2–10.0 mg/dL | Detect calcium imbalance |
| 25-hydroxyvitamin D | 40–60 ng/mL | Low vitamin D raises parathyroid hormone |
| LDL cholesterol | <100 mg/dL | Track lipid benefit |
| Triglycerides | <100 mg/dL | Track lipid benefit |
| ALT | 10–25 U/L | Liver safety check |
| eGFR | >90 mL/min/1.73 m² | Kidney function, affects parathyroid hormone |
| P1NP | No established target; track change from own baseline | Bone-formation activity |
| Bone density (dual-energy X-ray scan) | T-score above −1.0 | Bone outcome |
| Waist circumference | Waist-to-height ratio <0.5 | Central fat outcome |
| Blood pressure | <120/80 mmHg | Additive lowering with drugs |
Cadence: Fasting glucose weekly for the first 4 weeks if on glucose-lowering drugs; lipids, glucose, parathyroid hormone and calcium at 12 weeks; full panel at 24 weeks before any decision to continue; bone density scan 12–24 months after starting a bone protocol.