Guide · Functional water
What is functional water?
Short answer
Functional water is packaged water with something added to do a job beyond hydration: electrolytes for sweat loss, vitamins, protein, or a specific ingredient such as HMPA or L-carnitine. It's only as useful as that ingredient, at that dose, for you. Check the amount per serve, the sugar, the evidence behind it and a batch lab report.
Types of functional water, and what the evidence says
| Type | What's added | Useful for | Evidence |
|---|---|---|---|
| Electrolyte water | Sodium, potassium, sometimes magnesium | Replacing salts lost in heavy sweat or long exercise | Solid for real losses; not needed for everyday drinking |
| Vitamin water | B vitamins, vitamin C and others | Topping up vitamins | Most people get these from food; some versions carry a lot of sugar |
| Protein water | Whey or collagen protein | A light protein serve | Protein is protein: compare grams per bottle with the price |
| Alkaline or ionised water | Raised pH, usually 8–9.5 | Taste | No good evidence of health benefits; a systematic review found no support for it against cancer |
| Hydrogen water | Dissolved hydrogen gas | Not established | Small, short studies; no consistent benefit shown |
| HMPA water | HMPA, a compound from fermented rice bran | Visceral fat (studied) | One company-reported 12-week human study at 23 mg a day; otherwise mouse studies |
| L-carnitine water | L-carnitine | Moving fat into cells to be burned | 37 trials: about 1.2 kg more weight loss, mostly near 2 g a day |
Sources: Fenton and Huang, 2016 (alkaline water), Talenezhad et al., 2020 (L-carnitine), HMPA research tracker.
Is functional water better than plain water?
For hydration, no. The added ingredient doesn't hydrate you any better, except electrolytes after you've lost a lot of salt through sweat. A functional water is worth paying for only if you want its ingredient, at that dose, and the evidence behind it convinces you. Otherwise, plain water is the better buy.
The one benefit almost any unsweetened functional water has is what it replaces. A 330 mL sugary soft drink has about 140 calories; swapping one a day for water removes about 4,000 calories a month. More in do fat loss drinks work?
How to choose a functional water (any brand)
- Name the ingredient and the amount per serve. "With L-carnitine" means little without milligrams.
- Compare the dose with the research. HMPA was studied at 23 mg a day; L-carnitine's trials mostly used 1–3 g a day. A drink far below the studied dose is mostly water.
- Check the sugar. A sweetened functional drink can carry as much as a soft drink. The "total sugars" line on the label tells you.
- Find the FSSAI licence number on the pack. Packaged food sold in India must print it, along with the FSSAI logo.
- Ask for the batch lab report. It should show the measured amount of the active ingredient and the safety tests. Here's how to read one.
- Work out the price per dose, not per bottle.
Functional water in India
India's water aisle has moved past plain mineral water: alkaline, electrolyte and vitamin waters are now common, and ingredient waters are starting to arrive. Japan went first with HMPA: Suntory's Tokusui, a 600 mL water with 23 mg of HMPA, launched in October 2025. As of November 2026 we're not aware of any Indian brand selling HMPA water.
New ingredients need FSSAI approval before they're sold as food in India. Any brand selling one should be able to tell you its status. We'll publish ours on this site before Get Waisted goes on sale.
Get Waisted's two functional waters
| HMPA Water | L-Carnitine Water | |
|---|---|---|
| What's added | HMPA, from fermented rice bran | L-carnitine |
| Amount per can | Target 23 mg, the daily amount in the human study | Being set with the lab; printed on the can |
| Studied for | Visceral fat | Carrying fat into cells to be burned |
| Can | 330 mL aluminium | 330 mL aluminium |
| Lab report | Every batch, opened by the QR on the can | Every batch, opened by the QR on the can |
| Status | Batch in the lab | First batch in development |
Questions people ask
What is functional water?
Packaged water with an added ingredient meant to do something beyond hydration, such as electrolytes, vitamins, protein, HMPA or L-carnitine. Its value depends on that ingredient and its dose.
What are the benefits of functional water?
Only those of what's added. Electrolytes help after heavy sweating, protein water is a protein serve, and ingredient waters like HMPA or L-carnitine carry the modest effects seen in their studies. For plain hydration it's the same as water.
Is alkaline water good for you?
There's no good evidence that it improves health. Your stomach is strongly acidic and your body keeps blood pH in a tight range whatever you drink. It's safe for most people; it just isn't medicine.
What are some functional water brands in India?
Most functional waters in India are alkaline, electrolyte or vitamin waters. Get Waisted is making two ingredient waters, HMPA Water and L-Carnitine Water. Whichever brand you look at, compare the dose, the sugar, the evidence and the batch lab report.
What is the difference between functional water and flavoured water?
Flavoured water adds taste. Functional water adds an ingredient meant to do something. Some products are both; the ingredient list tells you which.
Is electrolyte water the same as ORS?
No. Oral rehydration solution (ORS) is a medical formula with set amounts of salts and glucose for treating dehydration, for example from diarrhoea. Electrolyte waters usually carry less and aren't a substitute when someone is ill.
Can I drink functional water every day?
It depends on the ingredient and the dose. Check the amount per serve against what was studied and what's considered safe, and ask a doctor first if you're pregnant, on medication or managing a health condition.
Sources
- 01Fenton T.R., Huang T. (2016). Systematic review of the association between dietary acid load, alkaline water and cancer. BMJ Open 6:e010438.Peer-reviewed · systematic review
- 02Talenezhad et al. (2020). Effects of L-carnitine supplementation on weight loss and body composition: a systematic review and dose-response meta-analysis of 37 randomized controlled clinical trials. Clinical Nutrition ESPEN 37:9–23.Peer-reviewed · meta-analysis · humans
- 03ReFa Slim Up Vinegar: 12-week HMPA study summary (74 adults, BMI 23–30, 23 mg/day).Company-reported · humans
- 04Suntory press release SBF1624: launch of Tokusui (Japanese).Manufacturer
- 05FSSAI: Frequently asked questions on the Food Safety and Standards (Labelling and Display) Regulations, 2020.Regulator (India)
Keep reading
- Guide · TransparencyWhat does lab-tested mean?What lab-tested and third-party tested really mean, how to read a lab report or CoA, verify a NABL lab, and what FSSAI requires (and doesn't). Five checks.→
- Guide · CategoryWhat is HMPA water?What is HMPA water, does it work, is it safe and can you buy it in India? A plain-English guide to the rice-bran water from Japan, with every study linked.→
- Guide · IngredientWhat is L-carnitine?L-carnitine carries fat into your cells' mitochondria to be burned. What it does, its real benefits, veg and non-veg sources, the forms, and how much people take.→
Both waters · in the lab
Report first. Can second.
HMPA Water and L-Carnitine Water, each with a report for every batch. Reserve a pack free.