Apple Health Outcome
10 compoundsin Regimen’s catalog are configured to track weight via Apple Health. Each one shows the dose range, listed benefits, and every outcome it’s set up to monitor. Tap through to plan a dose with the free reconstitution calculator.
Modern weight-loss peptides act on the body’s appetite-regulation system rather than on metabolism directly. GLP-1 receptor agonists (semaglutide, liraglutide) and the GIP/GLP-1 dual agonist tirzepatide bind to receptors in the hypothalamic arcuate nucleus, slow gastric emptying, and increase satiety signaling. The result is a sustained reduction in caloric intake without conscious calorie counting.
In the STEP 1 trial, adults with overweight or obesity who took once-weekly semaglutide 2.4 mg lost a mean 14.9% of body weight over 68 weeks, compared with 2.4% in the placebo group. Tirzepatide 15 mg, tested in SURMOUNT-1, drove a mean 22.5% weight reduction — the largest effect size reported for any anti-obesity medication to date. Newer triple-agonist compounds such as retatrutide (GLP-1 + GIP + glucagon) are in phase 3 trials with early signals exceeding 24%.
Older catabolic peptides (CJC-1295, ipamorelin, AOD-9604) are sometimes used adjunctively to preserve lean mass during a caloric deficit, but the primary driver of weight loss in modern peptide protocols is the incretin class.
Anchor citation: Wilding JPH et al.. Once-Weekly Semaglutide in Adults with Overweight or Obesity. New England Journal of Medicine, 2021.
10 compounds
GLP-1 Receptor Agonist
A once-weekly GLP-1 receptor agonist for weight management and metabolic health.
Tracks
GIP / GLP-1 Dual Agonist
A once-weekly dual GIP and GLP-1 receptor agonist delivering superior weight loss and metabolic improvements compared to GLP-1 monotherapy.
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GLP-1 Receptor Agonist (Saxenda / Victoza)
Daily injectable GLP-1 receptor agonist FDA-approved for type 2 diabetes (Victoza, up to 1.8 mg/day) and chronic weight management (Saxenda, up to 3.0 mg/day). Slows gastric emptying, increases satiety, improves glycemic control, and reduces cardiovascular events in T2D.
Tracks
GIP / GLP-1 / Glucagon Triple Agonist
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Long-Acting Amylin Analog
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Oral Ghrelin Mimetic / GH Secretagogue
An orally bioavailable, non-peptide ghrelin receptor agonist that produces sustained increases in GH and IGF-1 with once-daily dosing. Taken as a capsule — no reconstitution needed. Studied for sarcopenia, GH deficiency, and recovery support.
Tracks
ERRα/β/γ Agonist Exercise Mimetic
A pan-agonist of the estrogen-related receptor (ERR) family — most potent at ERRα — described as an 'exercise mimetic.' Preclinical mouse studies show increased energy expenditure, fatty acid oxidation, and reduced fat mass accumulation.
Tracks
In published head-to-head data, tirzepatide produces the largest mean reduction. SURMOUNT-1 reported a 22.5% mean weight loss at the 15 mg dose over 72 weeks, compared with semaglutide’s 14.9% over 68 weeks in STEP 1. Retatrutide is showing larger effect sizes in early-phase trials but is not yet FDA-approved. For people with type 2 diabetes the effect sizes are smaller across all three compounds, typically by 4–6 percentage points.
Most users see scale movement within the first 2–4 weeks of starting at a low titration dose. The dose-titration schedule is conservative on purpose — starting at semaglutide 0.25 mg or tirzepatide 2.5 mg weekly — to reduce GI side effects. The bulk of the weight loss in the STEP and SURMOUNT trials accumulated between weeks 16 and 60, with the curve flattening near the end of the trial period.
Yes. Regimen logs each GLP-1 injection, pulls weight from Apple Health, tracks injection sites on a human body diagram, and ties side effects to specific doses via the Reactions Journal. Both GLP-1 pens (semaglutide, tirzepatide, liraglutide) and research-grade vial formulations are in the catalog. The PDF report compiles dose history with the weight trend so your prescriber can see them together.
Body composition data from the SURMOUNT and STEP trials show that roughly 25–40% of the total weight lost is lean mass when no resistance training or protein-floor intervention is in place. Adding strength training and maintaining 1.2–1.6 g/kg protein intake substantially preserves lean mass. Some users add adjunctive peptides such as CJC-1295/ipamorelin or BPC-157 during a cut for this reason, though the human evidence for muscle-sparing effects from those compounds is limited.
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Other outcomes