Raising your growth hormone and IGF-1 numbers is not the same as building muscle, and the research makes that gap very clear. THE SCIENCE Tesamorelin (human RCT). In a 26-week NEJM trial of 412 adults with HIV and abdominal fat buildup, the dose studied in this trial (2 mg daily) cut visceral fat by 15.2% vs. a 5.0% increase on placebo, and triglycerides fell by 50 mg/dL. IGF-1 rose 81%. More people on tesamorelin dropped out due to side effects. Regulatory status: FDA-approved (Egrifta, 2010) only to reduce excess visceral abdominal fat in adults with HIV-associated lipodystrophy. FDA notes joint pain, muscle pain and small rises in blood sugar/HbA1c among side effects. It has not been tested as a muscle-builder in healthy, training adults. CJC-1295 (human, hormone levels only). In healthy adults (JCEM 2006), single doses raised GH for several days and IGF-1 for about 9 to 11 days, with a half-life of roughly 6 to 8 days. That study measured blood levels, not muscle, strength or fat loss. Regulatory status: not FDA-approved. FDA's compounding safety list flags possible immune reactions, impurity concerns, and reported serious events including increased heart rate and a vasodilatory reaction. Ipamorelin (limited human data). Not FDA-approved. FDA placed it in Category 2 (significant safety concerns) for 503B compounding in 2023, citing immune-response risk and a published study reporting serious adverse events, including death, with IV use for gastric motility. No human trial shows it builds muscle or burns fat. The bigger picture: growth hormone itself (human evidence). An Annals of Internal Medicine systematic review of 18 study populations in healthy older adults found GH increased lean mass by about 2.1 kg and reduced fat mass by about 2.1 kg, with no change in body weight. But it also raised rates of swelling (edema), joint pain, carpal tunnel and gynecomastia, plus a trend toward diabetes/impaired glucose. Part of a DXA "lean mass" gain can be fluid, not contractile muscle. The authors concluded GH cannot be recommended as an anti-aging therapy.

Federal health officials are reportedly drafting a stopgap that would let some compounding pharmacies sell certain unapproved peptides before formal rules are written, but nothing has been announced yet. (1)(2) WHAT IT IS On October 7 The Washington Post reported, citing two people familiar with the matter, that the administration is preparing a temporary measure allowing some previously restricted peptides to be sold while regulators write new rules. (1)(2) The plan has not been announced, its timing could change, it is not known which peptides would be included, and HHS did not comment. (2) As of a tracker update on October 12, no FDA guidance or Federal Register notice had been published. (5) WHAT THEY FOUND (THE BACKSTORY IN NUMBERS) In July, FDA's Pharmacy Compounding Advisory Committee reviewed 7 peptides for the 503A "bulks list," the list of ingredients compounding pharmacies may use. (3)(4) • BPC-157, KPV and TB-500 were backed 8-6 with 1 abstention. (3) • MOTS-c was backed 7-5 with 2 abstentions. (3) • Semax and Epitalon also cleared by similarly tight margins. (3) • Emideltide was rejected 7-6 with 1 abstention. (3) FDA's own reviewers had recommended that none of the 14 substances (7 peptides, each in two salt forms) be added to the list. (4) Their briefing found the available studies, including five BPC-157 trials, too short and small to establish safety or effectiveness. (3) HOW IT WORKS A committee vote does not change the law. FDA has to accept the advice and go through a proposed rule, a public comment period and a final rule before a peptide can legally be compounded from bulk. (3) A temporary plan would likely work through "enforcement discretion," meaning FDA chooses not to act against certain compounding while rules are pending; that is analysts' reading, not an official description. (5) The pharmacy compounding trade group says it asked FDA for exactly this, paired with patient disclosures, serious adverse event reporting and data collection. (2)

The scale tells you how much weight you lost. It doesn't tell you what you lost, and on GLP-1 drugs a real chunk of it isn't fat. THE SCIENCE Semaglutide (STEP 1, human RCT, DXA substudy of 140 people, 2.4 mg weekly as the dose studied, 68 weeks): total fat mass fell 19.3% and lean body mass fell 9.7% from baseline. Fat went down about twice as fast as lean, which is good news, but lean tissue still dropped meaningfully. Semaglutide 2.4 mg is FDA-approved for chronic weight management (Wegovy). Tirzepatide (SURMOUNT-1, human RCT, DXA substudy of 160 people, pooled 5/10/15 mg doses studied, 72 weeks): body weight fell 21.3% vs 5.3% on placebo. Fat mass fell 33.9% and lean mass fell 10.9%. Roughly 75% of the weight lost was fat and 25% was lean mass, and that split held across sex and age subgroups. Tirzepatide is FDA-approved for chronic weight management (Zepbound). Retatrutide (GLP-1/GIP/glucagon) is still investigational and not FDA-approved, so detailed body-composition data are still coming. Two honest caveats: DXA "lean mass" includes water and organs, not just skeletal muscle, and these trials did not include a structured lifting program. So the numbers above are what happens with drug plus usual lifestyle advice, not drug plus serious training. The tool we have the strongest evidence for protecting muscle is the one you control: resistance training. THE WORKOUT / TIPS The 2026 ACSM position stand on resistance training (an umbrella review of 137 reviews and 30,000+ participants) keeps it simple: train every major muscle group at least 2x per week, progress the load over time, and for muscle size aim for about 10 sets per muscle group per week. Training to failure, machines vs free weights and fancy periodization were optional, not required. Here is a 2-day full-body plan that hits those targets (do A and B each once a week; add a third day by repeating A when you're ready): DAY A 1. Goblet squat or leg press: 3 x 8-12 2. Dumbbell bench press or push-ups: 3 x 8-12

More than 25 people in at least four states got sick after compounded glutathione injections and IVs made from a supplement-grade ingredient, and the story is back in the news this weekend. (1)(2) WHAT IT IS Glutathione is a small peptide (three amino acids) that wellness clinics sell as IV drips and shots for "detox," immunity and energy. In July 2026, Texas health officials alerted the CDC to patients who got sick after IV glutathione at an outpatient wellness clinic. CDC and FDA have been investigating since. (1) WHAT THEY FOUND • CDC counts more than 25 cases in Texas, Washington, Florida and New York. At least 3 people were hospitalized, all after IV glutathione. One was critically ill, needed intensive care, and was treated for shock and abnormal blood clotting. No deaths are listed. (1) • FDA said it knew of at least 30 patients with adverse events after IV glutathione. The ingredient traced back to one supplier (Medisca, lot 229536) and was labeled "dietary supplement grade." (3) • Three Texas compounding pharmacies recalled products for elevated endotoxin: Victory Medical Center Pharmacy, Optimal Balance Pharmacy and Centric Compounding. (1)(4)(5) • Centric's recall also covered Myer's Cocktail and Tri-Immune Boost vials made with the same ingredient, shipped nationwide by home delivery. It received 9 reports of fever, chills, chest pain, nausea or vomiting, headache and malaise. (5) • Victory's reports included fever, chills, severe headache, vomiting, rapid heart rate, blood pressure changes and injection-site reactions. (4) HOW IT WORKS Endotoxin is a bacterial contaminant. Once injected, it can set off a strong inflammatory reaction: fever, chills, body aches, low blood pressure and, at worst, shock. (1)(5) The core problem was the raw material. FDA's position is that every ingredient in an injectable has to be made to standards that fit that route, and that testing the finished vial is not a substitute for building quality in from the start. (3)(6)

Retatrutide, Lilly's once-weekly "triple agonist," has now hit its main weight-loss goal in multiple Phase 3 trials. Here's where the evidence stands. WHAT IT IS Retatrutide activates three hormone receptors at once: GLP-1 and GIP (like tirzepatide) plus glucagon. The glucagon arm is thought to raise energy expenditure and help clear liver fat, on top of the appetite reduction from GLP-1/GIP. WHAT THE TRIALS FOUND (80 weeks, weekly injections, randomized vs. placebo) TRIUMPH-1: 2,339 adults with obesity/overweight, no diabetes • Average weight loss: 19.0% (4 mg), 25.9% (9 mg), 28.3% (12 mg) • At 12 mg, 45% of people lost 30% or more of their body weight • In a 104-week extension (BMI 35+), the 12 mg group averaged 30.3% loss TRIUMPH-2: 1,152 adults with type 2 diabetes and obesity/overweight • Weight loss: 12.7% / 19.1% / 20.8% vs. 4.0% placebo • A1C dropped about 1.4–1.6 points vs. 0.2 on placebo TRIUMPH-3: 1,949 adults with severe obesity and established heart disease • Weight loss: 21.6% (9 mg) and 22.6% (12 mg) vs. 3.2% placebo • Triglycerides fell 37%, systolic blood pressure about 9 mmHg, hsCRP (inflammation marker) about 51% at 12 mg • Heart-event results were inconclusive: too few events to show benefit or harm THE TRADE-OFFS • GI side effects are common and dose-related: nausea hit up to 42% at the top dose in TRIUMPH-1 (vs. 15% placebo), plus diarrhea, constipation and vomiting • Dysesthesia (abnormal skin sensations like tingling) showed up more than with placebo, mostly mild to moderate • Stopping due to side effects: roughly 4–13% depending on dose and trial, vs. about 5% on placebo HOW STRONG IS THIS? Strong: large, randomized, double-blind human trials. One caveat: TRIUMPH-2 and -3 are company-announced topline results; full peer-reviewed data is still to come. REGULATORY STATUS Investigational. Not FDA-approved for any use. Lilly says it plans to submit for U.S. approval in Q1 2027. Anything sold as "retatrutide" today is not an approved product.