Compound
semaglutide
Every Peptide Proof article that examines the evidence on semaglutide.
What Happens to Blood Sugar After Stopping a GLP-1?
In the tirzepatide withdrawal trial that tracked this directly, HbA1c drifted upward in step with how much weight came back — from a 0.14 percentage-p…
Systematic reviewDo GLP-1s Affect Bone Density?
The published meta-analyses disagree with each other. A 25-study pooled analysis in people with type 2 diabetes found GLP-1 receptor agonists were lin…
Randomized controlled trialDo GLP-1s Affect Heart Health?
In the SELECT trial — 17,604 adults with obesity and preexisting cardiovascular disease, but not diabetes — semaglutide reduced the combined rate of c…
Human clinical trialDo GLP-1s Work Differently in Older Adults?
In the largest post hoc analyses available, weight loss and cardiometabolic improvements with tirzepatide were broadly similar in adults 65 and older …
Systematic reviewDoes Protein Intake Preserve Lean Mass While Losing Weight?
A 2020 meta-analysis of 18 randomized trials found that eating more protein than the RDA (0.8 g/kg/day) preserved an extra 0.36 kg of lean mass during…
Randomized controlled trialDoes Resistance Training Protect Muscle During GLP-1 Weight Loss?
The only completed randomized trial to combine supervised exercise with a GLP-1 drug found the combination cut body-fat percentage roughly twice as mu…
Human clinical trialHow Long Do People Actually Stay on GLP-1s?
Considerably less long than clinical trials suggest. In a large US commercial insurance claims analysis, only 32.3% of people starting a GLP-1 for obe…
Human clinical trialHow Small Is Too Small? Sample Size, Explained
Sample size determines what a study can detect, not just how confident it can be. Early dose-finding work on the growth-hormone secretagogue MK-677 te…
Human clinical trialIs 'Food Noise' a Real, Measurable Thing?
It started as a patient-coined term with no formal clinical definition, and researchers are still building the tools to measure it. A 550-person retro…
Human clinical trialHow Much Weight Do People Actually Lose Outside of Clinical Trials?
In the pivotal STEP 1 trial, semaglutide produced 14.9% average weight loss over 68 weeks (n=1,961); tirzepatide's SURMOUNT-1 trial produced up to 20.…
Human clinical trialRelative vs. Absolute Risk: The Most Common Trick in Health Headlines
In the SELECT trial, semaglutide reduced major cardiovascular events by 20% relative to placebo — the number most headlines led with. But using the tr…
Randomized controlled trialSemaglutide vs Tirzepatide: What Do Head-to-Head Trials Show?
One published head-to-head randomized trial exists: SURMOUNT-5, comparing the maximum tolerated doses of each drug in 751 adults with obesity. Tirzepa…
Human clinical trialWhat 'Statistically Significant' Actually Means
A p-value answers one narrow question: if the treatment truly did nothing, how likely is a gap this large between groups to appear by chance alone? In…
Systematic reviewWhat Happens to Metabolic Rate During Rapid Weight Loss?
Across a systematic review of 33 controlled studies (2,528 participants), resting energy expenditure dropped more than body-composition changes alone …
Systematic reviewWhat Side Effects Were Actually Reported in the Trials?
Gastrointestinal events — nausea, vomiting, diarrhea, constipation — were consistently the most common adverse events across every major trial, and th…
Randomized controlled trialWhy Am I Still Hungry on a GLP-1?
In controlled feeding trials, semaglutide cut how much food people ate at a free-choice meal by roughly 35-39% compared with placebo, and reduced self…
Systematic reviewHow Much of the Weight Lost on GLP-1s Is Muscle?
Across 35 randomized trials, the median share of total weight loss coming from muscle-related measures was about 28% — but the range was enormous, fro…
Human clinical trialWhy Does Weight Come Back After Stopping Semaglutide?
In the trial that followed people for a year after they stopped, participants regained about two-thirds of the weight they had lost. A separate trial …
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