Glycerol Monostearate: Does It Actually Work—or Just Weigh You Down?
At Custom Gains, we’re not here to peddle hype—our job is to give you the facts, rooted in science, so you can build a supplement stack that actually works for you. Glycerol Monostearate (GMS) gets tossed around as a hydration and pump booster, but the research tells a different story at doses you’d actually use. We’re digging in for the runner, lifter, or fighter who wants results—not placebo vibes. Here’s the unfiltered evidence on Glycerol Monostearate in supplements, why it’s iffy at best, and why we’re not sold—but you decide.
What the Studies Say: The Hard Data on Glycerol Monostearate
We’ve pulled 10 peer-reviewed studies on glycerol (GMS or plain)—no guesswork, just what’s been tested. Here’s the table, straight up:
Custom Gains Scientific Evidence on Glycerol Monostearate and Glycerol
| Claim | Directly Tested? | Recent? (≤5 yrs) | Peer-Reviewed? | Study Design | Dosage Tested | Effect Size | Confidence Level |
|---|---|---|---|---|---|---|---|
| Boosts body water | ✅ | ✅ | ✅ | RCT | 1-1.5g/kg (70-100g) | 400-700ml extra | High – Big doses |
| Ups endurance in heat | ✅ | ✅ | ✅ | RCT | 1g/kg (70g) | 5-10% longer | Medium-High – High dose |
| Enhances muscle pump | ✅ | ❌ | ✅ | Limited RCTs | 20-25g | Subjective fullness | Medium – Thin data |
| Eases heart strain | ✅ | ✅ | ✅ | RCT | 1g/kg (70g) | 3-5% HR drop | Medium – Big dose |
| Lowers core temp | ✅ | ✅ | ✅ | RCT | 1-1.5g/kg (70-100g) | 0.3-0.6°C drop | Medium – High dose |
| Beats plain glycerol | ❌ | ✅ | ✅ | Formulation | N/A | Mix/stability edge | Medium – No perf data |
| Boosts anaerobic power | ❌ | ❌ | ✅ | Limited | 1g/kg (70g) | Weak/inconsistent | Low – Unproven |
| Improves hydration at low dose | ❌ | ❌ | ❌ | None | 2-10g | Untested | Low – No data |
| Pump at low dose | ❌ | ❌ | ❌ | None | 2-10g | Untested | Low – No data |
| Endurance at low dose | ❌ | ❌ | ❌ | None | 2-10g | Untested | Low – No data |
Studies Reviewed
- van Rosendal SP, et al. Sports Med. 2020. 1-1.5g/kg glycerol ups water 400-700ml. Link
- Patlar S, et al. J Hum Kinet. 2022. 1g/kg glycerol aids aerobic performance. Link
- Nelson JL, et al. Sports Med. 2019. 25g glycerol boosts fullness perception. Link
- Wagner DR, et al. J Appl Physiol. 2020. 1g/kg glycerol cuts HR strain. Link
- van Rosendal SP, et al. Nutr Metab. 2021. GMS mixes better than glycerol. Link
- Lyons TP, et al. Med Sci Sports Exerc. 2019. 1.2g/kg glycerol drops temp 0.5°C. Link
- Wingo JE, et al. J Athl Train. 2018. 1g/kg glycerol aids heat endurance. Link
- Goulet ED, et al. Int J Sport Nutr Exerc Metab. 2020. 1g/kg glycerol boosts endurance 5-10%. Link
- Easton C, et al. Int J Sport Nutr Exerc Metab. 2022. 1g/kg glycerol aids hydration. Link
- Montner P, et al. Int J Sports Med. 2019. 1.4g/kg glycerol extends cycling time. Link
The Dose Problem: Studies Love Big, You Don’t Need That
Here’s the catch: every study showing solid results—hydration, endurance, pumps—uses massive doses. Take a 200lb (90.7kg) person: 1g/kg means 90.7g of glycerol. GMS, with 5-12% free glycerol, could mean 750g+ of powder to hit that mark—absurd for a shaker, your stomach, or your wallet. Even at 20-25g (lowest studied), you’re way past practical. Studies pair this with 1.5-2 liters of water, not the 18oz (~500ml) you’d mix in a pre-workout, mid-workout, or post-workout drink.
At 1-10g—the most we’d ever include in a Custom Gains packet—you’re getting 100-1200mg of active glycerol. No study tests this range. Hydration might nudge up (50-100ml?), pumps might feel real to some, but science doesn’t back it. The big wins—400ml water, 5-10% endurance, 0.5°C temp drop—are tied to doses you can’t realistically use.
Why We Don’t Push Glycerol Monostearate at Custom Gains
We’re rooted in science, not hearsay. GMS is in our lineup because some users swear by the “full” feeling at 5-10g—fair enough, placebo or not, that’s your call. But the proof? It’s all at 20g+, often 70-100g, doses no one’s mixing into an 18oz drink. With GMS’s low glycerol content (5-12%), 5g delivers maybe 250-600mg of glycerol—miles from the 70g studies prove works. For comparison, you’d need a scoop the size of a protein shake to match research, and even then, it’s overkill for most.
We’re not here to force ingredients on you. Of the options in our arsenal, GMS ranks low—science says it’s a stretch at usable doses. If you’re after hydration or pumps, other picks like electrolytes or citrulline have tighter data at 8 grams. GMS might feel good, but we’re about results you can measure, not vibes. Still, it’s your stack—try it if you want. We’ve got the facts; you decide.
Who Might Still Want Glycerol Monostearate?
- Pump Chasers: Like the “full” look at 5-10g? Some do.
- Heat Warriors: Training in 30°C+? Might nudge hydration.
- Post-Cut Fighters: Rehydrating fast? Could help a bit.
- Experimenters: Want to test it? Your call.
Who Should Skip It?
- Science Buffs: No proof at 2-10g? Pass.
- Strength Lifters: No power gains? Meh.
- Budget Users: Cash tight? Better bets exist.
- Short Sessions: 30-min workouts? Pointless.
FAQs About Glycerol Monostearate—No BS
- Does Glycerol Monostearate improve endurance?
Yes—at 70g+ (1g/kg), 5-10% in heat. 5-10g? No data (Source #8). - What’s the best Glycerol Monostearate dosage for pump?
Studies say 20-25g; 5-10g untested, anecdotal only (Source #3). - How much GMS for hydration?
70-100g (1-1.5g/kg) adds 400-700ml—5-10g unstudied (Source #1). - Can Glycerol Monostearate fight heat stress?
0.3-0.6°C drop at 70g+; 5-10g unknown (Source #6). - Is Glycerol Monostearate better than glycerol?
Mixes easier—no performance proof (Source #5). - Does Glycerol Monostearate bloat you?
No—muscle water at high doses (Source #2). - Can Glycerol Monostearate boost power?
No evidence—endurance focus (Source #4). - Is Glycerol Monostearate worth it at 5g?
No studies—too low vs. 20g+ proven (Source #9). - Does Glycerol Monostearate mix with pre-workout?
Yes—clean at 18oz, but effect’s weak (Source #7). - Can it rehydrate post-weight cut?
Yes—70g+ works; 5-10g untested (Source #10).
Why Custom Gains Lets You Choose
We’re not about forcing picks—your stack, your rules. GMS is here, mixable in 18oz, because some like it. But we’re science-first: no solid data backs it at these doses. Each of our 20-packet boxes is your canvas—add GMS if you feel it, skip it if you don’t. Try it at https://customgains.com/pre-workout/.
Disclaimer: Your Call, Not Ours—Not Medical Advice
This is the evidence—my breakdown, not gospel. I’m no doctor or health pro; this isn’t medical advice. Custom Gains isn’t pushing Glycerol Monostearate—or anything. We’re handing you the science to build what works for you. Your stack, your responsibility.
Me—I’d skip GMS for citrulline; a buddy swears by 4g for pumps, another ditches it. No “must-have”—just options. Don’t like it? Drop it. Check with a pro before tweaking—your health, your game.