Here is the entire pitch in one sentence, so nobody has to hunt for it. Harlo takes the same 5 grams of creatine monohydrate you are already taking every morning and delivers it in a drink that also replaces the electrolytes you sweat out. One scoop, one glass, two jobs.
That sounds almost too simple to be interesting. It is worth about eight minutes of your time anyway, because the reason it works is not the convenience. It is that creatine and electrolytes are not two unrelated supplements that happen to fit in the same cup. They are physiologically connected, and the connection has been sitting in the research literature for thirty years while the supplement industry sold them in separate tubs.
We were paid to review this product. We still think that is the most interesting thing on the shelf right now, and the rest of this article shows the evidence.
- 5 gCreatine monohydrate. The full clinical dose, and specifically the monohydrate form that carries essentially all of the research behind creatine.[1]
- 1,000 mg+Electrolytes from real sea salt. A functional dose, not a flavouring pinch.
- 0 gSugar. Which matters when something becomes a daily habit.
- CertifiedNSF Certified for Sport. Independently batch tested for banned substances and label accuracy.
- FormatLight lemon, clean salty finish. Vegan, gluten free, non GMO. Mixes into cold water in about ten seconds.
What the combination actually does
Three things happen when you put these two in the same glass instead of taking one and ignoring the other. Each one is a separate mechanism, and each one is documented.
Your creatine has something to travel on
Creatine cannot cross into a muscle cell on its own. It is carried by a transporter that runs on sodium. Plain water gives that transporter nothing to work with.
The water you drink actually stays
Creatine pulls water into muscle and raises your fluid demand. Electrolytes are what let your body hold onto the fluid you drink rather than pass it straight through.
One habit instead of two
The single biggest reason creatine fails people is that they stop taking it. A drink you look forward to beats a chalky glass of water you tolerate.
That third one gets dismissed as soft, and it should not be. Adherence is the variable that quietly decides whether any supplement works. A perfect protocol you abandon in week five loses to a good one you keep for a year.
Two supplements, one glass, once a day
Try the format that finally makes sense.
A full 5 g clinical dose of creatine monohydrate plus over 1,000 mg of electrolytes from real sea salt. Zero sugar. NSF Certified for Sport. Backed by a 30 day money back guarantee.
Shop Harlo Now →Free returns within 30 days
The science, in three parts
This is the section our sponsor did not get to see before it went live, so take it as written by people with nothing to sell you.
Part one: the door into a muscle cell runs on sodium
Creatine is a polar molecule. It cannot drift across the fatty membrane of a muscle cell the way alcohol or oxygen can. It needs a dedicated transporter protein, and that protein is called SLC6A8.[2] Look it up in any review paper and you will find its full formal name, which is the single most useful fact in this article:
The sodium and chloride dependent creatine transporter.
Sodium and chloride are not a footnote in that name. They are the power supply. SLC6A8 is a symporter, meaning it has no energy source of its own, so it borrows one: it uses the sodium gradient your cells maintain across their membranes to haul creatine inwards against creatine's own concentration gradient. Every trip carries roughly two sodium ions and one chloride ion along with each creatine molecule.[2]
Creatine does not walk into a muscle cell. It gets carried. And the thing that carries it runs on sodium.
Figure 1 / How creatine actually enters a muscle cell
SLC6A8 couples creatine transport to the movement of sodium and chloride down their own gradients. This is why what you take creatine with has been shown to measurably change how much of it ends up stored in muscle.[2][3]
This is not a theoretical point. It has been tested directly. In 1996, a group at Nottingham gave subjects creatine either alone or alongside a co ingested vehicle, then took muscle biopsies. The co ingestion group accumulated roughly 60% more creatine in muscle.[3] The researchers attributed it to an insulin mediated augmentation of sodium dependent creatine transport, which is to say the effect ran through the sodium pump.
An honest caveat, since we would rather you trust the rest of this page: that particular study used a large dose of carbohydrate to drive insulin, and Harlo contains zero sugar. Harlo is not reproducing the insulin arm of that experiment. It is addressing the other half of the same mechanism, the sodium and chloride the transporter itself depends on. What the study establishes beyond argument is the principle: plain water is the one vehicle that contributes nothing.
Part two: creatine raises how much water you need
Creatine is osmotically active. Once inside a muscle cell it draws water in behind it, which is a substantial part of why creatine works at all. That intracellular water is not cosmetic puffiness, it is cell volumisation.
So taking creatine daily increases your body's fluid requirement. That is a feature, not a problem, but it does mean the hydration side of the equation stops being optional.
Part three: what you sweat out is saline, not water
The fluid you lose in training is not plain water. Across athletes, sweat sodium concentration averages around 42 mmol per litre and ranges from roughly 17 to 106 mmol per litre depending on the individual, which is somewhere between a quarter of a gram and two full grams of sodium lost per litre of sweat.[9] Meanwhile mild dehydration of about 2% of body mass measurably reduces strength, power and high intensity endurance.[10]
Put the three parts together and the standard routine looks strange. You take a compound that depends on sodium for its absorption and increases your fluid demand. You then lose sodium rich sweat in training. And you replace all of it with plain water.
Harlo's whole idea is that those are one problem, not three, and should be solved in one glass.
Side by side
| Creatine powder in water | Harlo | |
|---|---|---|
| Creatine dose | 5 g monohydrate | 5 g monohydrate |
| Electrolytes included | None | 1,000 mg+ from sea salt |
| Supports the sodium dependent transporter | No | Yes |
| Replaces training sweat losses | No | Yes |
| Sugar | None | None |
| Third party batch tested | Varies wildly by brand | NSF Certified for Sport |
| Something you look forward to | Chalky water | Light lemon, salty finish |
To be fair to the plain powder: it is cheap, it is the same molecule, and it works. Nothing here argues that creatine monohydrate in a tub is a bad product. The argument is narrower than that. It is that the five grams was never the hard part. Everyone gets the five grams right. Almost nobody thinks about the glass it arrives in.
What to expect, realistically
We are not going to promise you a transformation in a week, because that is not how creatine works and you would notice we were lying.
- Days 1 to 7 Mostly the hydration side. If you train regularly and have been drinking plain water, this is where the electrolytes are doing most of the visible work. Better fluid retention, less of the flat feeling late in a session.
- Weeks 2 to 4 Muscle creatine stores fill. At 3 to 5 g daily, without a loading phase, saturation takes roughly three to four weeks.[1] This is where the strength and repeat effort side starts showing up, usually in your later sets rather than your first.
- Week 4 onward Steady state. Full stores maintained by the daily dose. This is the point at which most people stop thinking of it as a supplement and start thinking of it as part of the morning.
Four weeks is the honest timeline
The 30 day guarantee covers exactly that window.
Which is convenient, because four weeks is roughly how long it takes to know whether this is working for you. If it is not, you send it back.
Shop Harlo Now →Trusted by 300,000+ athletes
The questions people actually ask
Do I need to do a loading phase?
No. Loading with around 20 g a day for five to seven days fills stores faster, but 3 to 5 g daily reaches the same saturation in about three to four weeks. The endpoint is identical. Loading only changes how quickly you get there.[1]
Will the extra sodium make me retain water or look puffy?
The water creatine draws in goes primarily into the muscle cell rather than under the skin. Measured properly, total body water rises without the intracellular and extracellular balance being distorted.[6] As for the sodium itself, 1,000 mg is roughly what you lose in a single litre of sweat if you are a heavier salt sweater.[9] It is replacement, not surplus.
Is it really just salt water with creatine in it?
Reductively, yes, and that is rather the point. The question worth asking is whether the salt belongs there. The formal name of the transporter answers it.
Is taking creatine every day safe?
The International Society of Sports Nutrition position stand reviewed doses up to 30 g per day sustained for five years and found no adverse effects in healthy or clinical populations.[1] Five grams sits a long way inside that. The usual caveats apply if you have kidney disease or are pregnant, in which case ask your doctor rather than a website.
Does the research all point one way?
Not entirely, and we would rather say so. A 2025 analysis of NHANES data covering nearly one hundred thousand people found higher dietary creatine intake associated with lower total body water, which complicates the simple story that creatine hydrates you.[11] Separately, a meta analysis of ten trials found no evidence that creatine harms heat tolerance or fluid balance, putting an old worry to rest.[8] Neither finding touches the transporter mechanism, which is the part this product is built on.
I do not train seriously. Is this for me?
Some of the most active current creatine research concerns cognition, recovery and healthy ageing rather than sport, and the position stand catalogues clinical applications well outside the gym.[1] The daily dose matters more than the training does.
Our verdict
Harlo did not invent a new molecule, and it is not claiming to. It took two things that were always physiologically linked, that the industry insisted on selling separately, and put them in the same scoop at doses that actually do something. Five grams of the researched form of creatine. A functional electrolyte load rather than a pinch. No sugar. Third party certified, which in an unregulated category is not a small thing.
The idea is obvious in hindsight. Most good ones are. The only real surprise is that it took thirty years.
References
- Kreider RB, Kalman DS, Antonio J, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. Journal of the International Society of Sports Nutrition. 2017;14:18. link.springer.com/article/10.1186/s12970-017-0173-z
- Farr CV, El-Kasaby A, Freissmuth M, Sucic S. Structural correlates of the creatine transporter function regulation. Amino Acids. 2016;48(8):1897-1911. pubmed.ncbi.nlm.nih.gov/26951207
- Green AL, Hultman E, Macdonald IA, Sewell DA, Greenhaff PL. Carbohydrate ingestion augments skeletal muscle creatine accumulation during creatine supplementation in humans. American Journal of Physiology. 1996;271(5):E821-E826. pubmed.ncbi.nlm.nih.gov/8944667
- Steenge GR, Simpson EJ, Greenhaff PL. Protein and carbohydrate induced augmentation of whole body creatine retention in humans. Journal of Applied Physiology. 2000;89(3):1165-1171. pubmed.ncbi.nlm.nih.gov/10956365
- Syrotuik DG, Bell GJ. Acute creatine monohydrate supplementation: a descriptive physiological profile of responders vs. nonresponders. Journal of Strength and Conditioning Research. 2004;18(3):610-617. pubmed.ncbi.nlm.nih.gov/15320650
- Powers ME, Arnold BL, Weltman AL, et al. Creatine supplementation increases total body water without altering fluid distribution. Journal of Athletic Training. 2003;38(1):44-50. pmc.ncbi.nlm.nih.gov/articles/PMC155510
- Creatine supplementation increases total body water in soccer players: a deuterium oxide dilution study. International Journal of Sports Medicine. 2016;37(2):149-153. pubmed.ncbi.nlm.nih.gov/26509366
- Lopez RM, Casa DJ, McDermott BP, Ganio MS, Armstrong LE, Maresh CM. Does creatine supplementation hinder exercise heat tolerance or hydration status? A systematic review with meta-analyses. Journal of Athletic Training. 2009;44(2):215-223. pmc.ncbi.nlm.nih.gov/articles/PMC2657025
- Baker LB, Barnes KA, Anderson ML, Passe DH, Stofan JR. Normative data for sweating rate, sweat sodium concentration and sweat sodium loss in athletes: an update and analysis by sport. Journal of Sports Sciences. 2019;37(20):2356-2366. pubmed.ncbi.nlm.nih.gov/31230518
- Judelson DA, Maresh CM, Anderson JM, et al. Hydration and muscular performance: does fluid balance affect strength, power and high intensity endurance? Sports Medicine. 2007;37(10):907-921. pubmed.ncbi.nlm.nih.gov/17887814
- Dietary creatine and hydration biomarkers in the general population: NHANES 1999-2023. Food Science and Nutrition. 2025. pmc.ncbi.nlm.nih.gov/articles/PMC12203408