Barrett’s Research

Your GLP-1 Guide Library

Starting a GLP-1 raises a lot of questions, and the internet is full of noise. We read the studies, talked through the trade-offs, and wrote it all down in plain language — how these medications actually work, the side effects worth planning for, how to eat and train so you keep your muscle, and what is coming next. Use these to walk into your next doctor's visit feeling prepared, not overwhelmed.

ScienceSide EffectsFitnessLifestyleTreatmentPipeline

The library

20 guides, sorted by what's on your mind

Every guide turns the research and clinical guidance into something you can actually use, with the key numbers up front and a quick FAQ at the end. Pick the question that's nagging you and start there.

Science

How GLP-1 Works

If you've ever wondered what semaglutide and tirzepatide are really doing inside your body, here's the science in plain, friendly language — no biochemistry degree required.

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Science

Food Noise

If your brain seems to think about food all day long, you're not imagining it — and you're not alone. Here's what 'food noise' is, why GLP-1 drugs quiet it, and the unexpected emotions that can follow.

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Side Effects

Ozempic Face

Losing weight quickly can change your face along with the rest of you. Here's why it happens, who's most likely to notice it, and the practical steps that help you keep your results without an aged look.

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Side Effects

Ozempic Teeth

GLP-1 medications can quietly affect your dental health — not by attacking your teeth, but through dry mouth and reflux. The good news: with a few simple habits, it's very preventable.

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Side Effects

Hair Loss

Noticing more hair in the shower drain? It can happen on GLP-1 medications, but it's almost always temporary and tied to rapid weight loss — not the drug itself. Here's what to expect and how to soften it.

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Fitness

Muscle Loss

A surprising share of the weight you lose on a GLP-1 can be muscle — but it doesn't have to be. Here's how to protect your strength, your metabolism, and your long-term results.

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Lifestyle

GLP-1 and Alcohol

A lot of people find they simply want to drink less on a GLP-1 — sometimes to their own surprise. Here's why that happens, what the research shows, and how to stay safe if you do drink.

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Fitness

GLP-1 and Exercise

The medication does the heavy lifting on weight loss, but how you move shapes how good you feel and how much muscle you keep. Here's a simple, sustainable way to train alongside it.

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Treatment

GLP-1 and PCOS

If you're living with PCOS, you've probably wondered whether these medications could help. The early evidence is encouraging — here's an honest look at the benefits, the unknowns, and what to plan for.

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Side Effects

GLP-1 Before Surgery

Have a procedure coming up? Because these medications slow your stomach, there's an important safety conversation to have with your care team beforehand. Here's what to know and do.

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Science

Heart Benefits

There's growing evidence that these medications protect your heart in ways that go beyond weight loss. Here's the trial data behind that claim, explained plainly and honestly.

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Treatment

Binge Eating Disorder

Binge eating disorder is exhausting and isolating, and these medications quiet some of the urges that drive it. Here's the promising early research, and the honest reasons it isn't the whole answer.

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Treatment

Liver Disease

Fatty liver disease often travels alongside weight and insulin problems — the very things these medications improve. Here's what the research shows about GLP-1s for MASLD and MASH, in plain language.

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Treatment

6-Week Results

If the scale is moving slower than you hoped in the early weeks, take a breath — that's completely normal and by design. Here's what to actually expect, and how to set yourself up for the months ahead.

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Treatment

Weight Regain

Worried about regaining weight if you ever come off the medication? It's a fair concern, and the data is honest about it. Here's what tends to happen, why it isn't your fault, and how to hold onto your results.

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Pipeline

Orforglipron

An effective GLP-1 in pill form, with no empty-stomach rules — that's the promise of Eli Lilly's orforglipron. Here's the trial data, the timeline, and what we know about pricing, explained simply.

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Pipeline

Retatrutide

By targeting three hormones instead of one or two, retatrutide has posted some of the biggest weight-loss numbers we've ever seen in trials. Here's what makes it different — and why it's not available yet.

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Side Effects

Ozempic Patch

Seen an ad promising an Ozempic skin patch? We're sorry to say it's almost certainly a scam. Here's why no real GLP-1 patch exists, how the actual drugs are delivered, and how to protect yourself.

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Treatment

Generic Ozempic

Hoping a cheap generic Ozempic is just around the corner? Not quite yet. Here's the patent reality, why compounded semaglutide isn't the same thing, and the realistic ways to pay less in the meantime.

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Science

Addiction Research

The same brain pathways that drive food cravings also fuel addiction — so could GLP-1 drugs help with alcohol, nicotine, and more? Here's an honest tour of an exciting but early field of research.

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Trying to choose a program?

We compared the six GLP-1 programs we trust so you don't have to

We rate each program on cost, safety, honesty, and how well it supports you along the way — and nobody pays us for a better spot. It's all here when you're ready to compare.

2-minute match quiz

Not sure which program is the right fit?

Answer six quick questions and we'll point you to the programs that suit your budget, your insurance, and how you want to be cared for.