New GLP-1 lean-mass news vs my 28-week DEXA scan

A 4.3 lb lean drop on a 34 lb total loss is honestly mild. The news headline makes it sound like everyone is melting muscle.

Mild? I dropped about 6 bls lean in 5 months and my squat and press both fell. DEXA error bars aren't that big.

Your ALT and CRP drops are the real story.

InBody told me I lost 7 lbs lean after a sauna. Dexa said 2. Hydration matters.

The STEP body-comp substudy is what the articles keep stripping for headlines. In that data, lean mass fell, but total fat fell way more, so lean percentage often improved. The bigger issue is strength and function, not just a DEXA pound count. If someone's squat is stable and protein is decent, a few pounds of lean over 6 months may not mean much clinically. If lifts are dropping, that's a different conversation. I'm not a doctor, just a lab-nerd who reads the supplements. The news piece also didn't mention that DEXA can shift with hydration and positioning. So the panic is probably premature, but it's worth tracking.

That's my gripe too. The STEP substudy showed lean percentage improving, yet the headline was basically 'GLP-1 eats muscle.'

The trial cohort also skews older and higher BMI than a lot of people posting here. I wish the articles would say that.

Grip strength and waist over DEXA pounds, then.

Check your scan conditions before you let that 4.3 lbs mess with your head. I'm 5'8", went 247 to 203 over about nine months, and my two DEXAs on the same machine read lean 158.2 then 156.0 — 2.2 lbs "lost" — except the second was 8am fasted after a heavy squat day two days prior and a low-carb week, and the tech told me glycogen and hydration alone can swing lean 1-3 lbs. I started scanning same time of day, same hydration, no lifting for 48 hours, and the next one showed lean up 1.4 lbs even though I'd dropped another 6 lbs of scale weight. Do the math on yours too: 34 lbs down with 4.3 lean means about 87% of your loss was fat, which is better than most

Your own numbers argue against the panic: 34 lbs down, 4.3 lean down means ~87% of loss came from fat. I track lean as a ratio to total mass, not raw pounds. Mine dipped 3.8 lbs around week 20, then held flat for 8 weeks while the scale barely moved. DEXA lean includes glycogen and water, so a hard lift or low-carb stretch can swing it. What does your lean trendline look like plotted against body weight instead of weeks? I’d bet the slope is nearly flat.

One thing I’d dig into before worrying: the regional DEXA breakdown. My total lean bounced around way more than my arms and legs did; most of the swing sat in trunk lean, which seems to carry a lot of water/glycogen/organ noise. If your leg lean and your lifts are holding steady, that 4.3 lb total number may read scarier than it is. Did your

Curious whether that 120g is spread out or mostly at dinner? I’m similar stats and my DEXA lean dipped 4 lb early, then stabilized once I moved protein to ~35g at breakfast/lunch and kept lifting 2x/wk. N=1, and the lean-mass trials are mixed, but per-meal distribution is the one variable I’d check before blaming the med. Are you logging protein timing or just daily total?

One thing I’ve started doing after a similar scare: pair DEXA with strength benchmarks. If my squat/row/hinge numbers hold or creep up, I trust the lean drop is more water/glycogen/scale noise. If they slide for 3–4 weeks, that’s my cue to tweak training volume or recovery, not panic. Are your main lifts trending flat, up, or down since week 0? Also, do you have a baseline waist measurement? For me, waist dropping while lifts held was the reassuring combo.

DEXA lean mass isn’t pure muscle. It loves water and glycogen. I work nights too. My lean number swung 3.1 lbs between scans 10 days apart—one after a rough shift, underhydrated; one after sleep and nrmal carbs. Same

Did the math on yours: baseline fat mass ~79 lb, now ~49 lb. That’s about 30 lb fat lost vs 4.3 lb lean — roughly 87% of your drop came from fat. With two kids and chaotic meals, I’d frame that as a win. One less noisy thing I track: waist at navel and which belt notch. My snack drawer is cheese sticks, jerky, roasted chickpeas; I grab one while making their lunches so I’m not just inhaling leftovers. Are your waist/belt numbers moving the same direction as the DEXA?

did you look at regional lean or bone mineral content on the reports? i nerd out on that. my total lean bounced around but arms/legs stayed flat while trunk lean dropped, which for me was mostly bloat/glycogen shifting. also: same DEXA machine + software version both times? different scanner or even a software update can make a couple lbs look like muscle loss. if your lifts are holding and waist is dropping, i’d trust the trend over one scan. what do your regional numbers say?

I had similar DEXA weirdness and just watched my lifts—my bench didn't budge, so I didn't sweat the lean dip.

solid improvements, and I’ve been the regain-and-restart guy too. One thing I’d check before stressing the 4.3 lb: were both scans on the same machine, same time of day, similar food/fluid timing, and did you lift hard within 24–48h before either? My clinic’s DEXA swung my lean by ~2 lb just from afternoon vs morning and a salty dinner. I also track waist and a couple of strength markers (chin-up reps, goblet squat

Hi, I’m brand-new hee and only on week one, so I’m mostly lurking. Your numbers actually look encouraging to me: 4.3 lb lean down against 34 lb total lost is around 13% of the loss, not the scary half-and-half some headlines imply. One thing I’d be curious about: was the follow-up DEXA on the same machine, similar time of day, and similar hydration/food/sodium timing? I’ve read scans

I treat DEXA lean mass as a 3-scan trend, because my clinic quotes roughly 1.5–2% precision on lean, which on your ~149 lb is about 2–3 lb of pure noise. Add hydration, sodium, carb timing, and whether you scanned before/after lifting, and 4.3 lb can shift a lot. Were both scans same machine, same fasting/fluid routine, and similar time of day? If yes, I’d lean on waist and lift numbers; if not, I wouldn’t overread it. Those A1c, ALT, and CRP moves are huge.

i’m on the road 3 weeks/month, and my DEXA lean number swings with hydration/sodium—one scan after a Vegas conference read 2 lb lower lean than 5 days later at home. I now book scans same time of day, same hydration, no red-eye before. If your last scan followed hotel food/travel, that 4.3 may be partly water. Did you have a travel week before it?

For what it's worth, 4.3 lb lean down with ~30 lb fat down is a ratio I’d take. I’m the spreadsheet guy who tracks this like vendor restocks. My 24-week scan: total lean -3.9 lb, but appendicular lean mass index -0.1 and leg press +35 lb. If your DEXA breaks out ALMI or regional lean, that’s the line I’d watch more than the total. Did yours list leg lean separately? Mine stayed almost flat while trunk dipped, which made me stop stressing the headline number.

Night shift guy here. One DEXA lean number wouldn’t make me change anything. What are your main lifts doing? If squat/row/press are flat or up and waist is down, 4 lb is noise. If they all dropped 10%+, that’s when I’d dig in. Also, creatine? Starting or stopping it can move lean mass via water and mess up scan-to-scan comparisons. I’d watch strength, tape, and how clothes fit, not just DEXA.

Hotel gym dumbbells and airport pretzels probably swing my lean number more than actual tissue 😂

Week one here too and this already made me feel less alone, thank you for sharing.