GLP-1 Receptor Agonists for Health & Longevity - Quick Reference Sheet

GLP-1 Receptor Agonists for Health & Longevity

Created on 07/02/2026 – Quick Reference based on Evidence Review created using AI4L / Opus 4.8 Audit

These injectable or oral medicines copy a natural gut hormone to curb appetite, steady blood sugar, and drive major weight loss. Large studies show reduced heart attacks, strokes, and death, plus kidney and liver benefits. Key trade-offs are digestive effects and muscle loss. Benefits fade after stopping, and the drugs are costly. (Full Review)

Protocol

Dosing
Once-weekly, lowest dose
Semaglutide or tirzepatide, escalating every 4 weeks toward maintenance as tolerated
Muscle preservation
High-protein diet + resistance training
Paired from the outset; protein ~1.2–1.6 g/kg daily, strength training 2–3× weekly
Timing
Any consistent day, weekly
Injectable: with or without food; oral semaglutide: empty stomach, ~30 min before food, drink, or medication
Time to effect
Weight loss
Months
Meaningful weight loss unfolds over months, with continued loss typically through 12+ months
Appetite suppression
Days to weeks
Appetite suppression begins within days to weeks
Glycemic improvement
Within weeks
Glycemic improvement is apparent within weeks

Benefits

Contraindications
  • Personal or family history of medullary thyroid carcinoma or MEN2
  • Known hypersensitivity
  • Pregnancy and breastfeeding
  • Severe gastroparesis
  • History of pancreatitis (caution)
  • Advanced diabetic retinopathy (caution)
  • Severe gastrointestinal disease (caution)
Key Interactions
  • Insulin and sulfonylureas (glipizide, glyburide, glimepiride)
  • Oral medications with narrow therapeutic windows (certain antibiotics, thyroid hormone, oral contraceptives)
  • Over-the-counter medications (acetaminophen, oral iron)
  • Supplement interactions (protein, vitamins, minerals, iron)
  • Supplements with additive effects (berberine, chromium, alpha-lipoic acid)

Risk & Side Effects

  • High: Gastrointestinal adverse effects; loss of lean muscle mass
  • Medium: Gallbladder disease; acute pancreatitis
  • Low: Diabetic retinopathy worsening; ischemic optic neuropathy; injection-site and heart-rate effects
  • Speculative: Thyroid C-cell tumors; long-term effects of lifelong use in healthy adults

Monitoring

Marker Target Why
HbA1c < 5.4% (functional); < 5.7% conventional Tracks glucose control and response
Fasting glucose 75–90 mg/dL (functional); < 100 conventional Early marker of glycemic response and hypoglycemia risk
Fasting insulin 2–5 µIU/mL (functional) Gauges insulin resistance improvement
Body composition (DEXA) Preserve lean mass; reduce visceral fat Detects muscle/bone loss versus fat loss
eGFR > 90 mL/min/1.73m² (functional); > 60 conventional Monitors kidney function and protection
Lipid panel Triglycerides < 80 mg/dL; HDL > 50 mg/dL (functional) Tracks cardiometabolic improvement
Ferritin / iron studies Ferritin 50–150 ng/mL (functional) Detects reduced iron absorption/intake
Vitamin B12 > 500 pg/mL (functional); > 200 conventional Screens for deficiency from reduced intake
Lipase Within lab reference range Screens for pancreatic irritation

Cadence: Baseline before starting; reassess ~4–12 weeks after starting and after each dose escalation, then every 3–6 months during maintenance, with body-composition and nutritional review at similar intervals

Qualitative Assessment

  • Energy levels and daily functional capacity
  • Strength and physical performance
  • Appetite and satiety changes
  • Gastrointestinal tolerability (nausea, bowel habits)
  • Sleep quality and mood
  • Cognitive clarity