MiO has zero carbohydrates and zero calories per serving, which technically makes it keto friendly by the numbers. But the full picture is more nuanced. Several ingredients in MiO, including its sweeteners and organic acids, have properties that could work against ketosis at a metabolic level, even though they won’t show up on a nutrition label.
What’s Actually in MiO
A half-teaspoon squeeze of MiO Original contains water, malic acid, citric acid, natural flavor, two artificial sweeteners (sucralose and acesulfame potassium), potassium citrate, gum arabic, sucrose acetate isobutyrate, Red 40, and a preservative. The macros are as clean as it gets: 0 grams of carbs, 0 grams of fat, 0 grams of protein, and 0 calories. On paper, it fits perfectly within any keto macro target.
MiO comes in several product lines. MiO Energy adds 60 mg of caffeine and B vitamins per squeeze. MiO Vitamins includes added B vitamins without caffeine. The base formula and sweetener system remain the same across all versions.
How the Sweeteners Affect Insulin
This is where things get complicated. Sucralose, the primary sweetener in MiO, has zero carbs and doesn’t raise blood sugar on its own. But research published in Diabetes Care found that when sucralose was consumed before a glucose load, it increased blood insulin levels compared to water alone. A separate randomized controlled trial in the American Journal of Clinical Nutrition found that sucralose decreased insulin sensitivity in healthy subjects.
Why does this matter for keto? Insulin is the hormone that tells your body to store energy rather than burn fat. Ketosis depends on keeping insulin low enough that your liver shifts to producing ketone bodies from fat. If sucralose nudges insulin higher, even modestly, it could slow that process. The effect from a single squeeze of MiO is likely small, but for people who add multiple squeezes to several bottles of water throughout the day, the cumulative exposure increases.
Acesulfame potassium, the second sweetener in MiO, has also been studied for similar insulin-stimulating effects through its activation of sweet taste receptors in the gut. These receptors trigger the release of hormones that can lead to higher circulating insulin levels.
Citric Acid’s Anti-Ketone Effect
Citric acid is one of the top ingredients in MiO by concentration. It’s a naturally occurring acid found in citrus fruits, and it plays a central role in your body’s energy metabolism. When citric acid is metabolized, it produces a compound called oxaloacetate, which diverts the raw materials your liver would otherwise use to make ketone bodies. Instead of those molecules entering the ketone-production pathway, they get burned for energy through a different route.
Animal research has demonstrated this directly. Rats given oral citric acid showed significantly reduced levels of ketone bodies in their blood. The researchers noted this wasn’t surprising, since citric acid metabolism “uses, rather than produces” the precursor molecules needed for ketogenesis. The anti-ketotic effects of citrate have been documented in scientific literature going back to the 1960s.
The amount of citric acid in a single MiO squeeze is small. But like the sweetener question, this becomes more relevant if you’re using MiO heavily throughout the day. Someone squeezing MiO into every glass of water is getting a steady drip of a compound that biochemically opposes ketone production.
The Practical Impact
For most people following a standard keto diet with a 20 to 50 gram daily carb limit, an occasional squeeze of MiO is unlikely to knock you out of ketosis. The quantities of sucralose, acesulfame potassium, and citric acid in a single serving are genuinely tiny, and your body can handle small metabolic nudges without losing its fat-burning state entirely.
The risk increases with volume. If MiO is your primary strategy for drinking enough water and you’re using it six, eight, or ten times a day, the cumulative effects on insulin signaling and ketone production become harder to dismiss. People who are metabolically insulin resistant or who struggle to get into deep ketosis may be more sensitive to these effects than someone who slips into ketosis easily.
If you’re tracking ketones with a blood meter and notice your readings are lower than expected, your water enhancer is worth examining as a variable. Try a week without it and compare your numbers.
Artificial Dyes and Clean Keto
Beyond the metabolic question, many keto followers who prioritize whole foods and minimal processing will have concerns about MiO’s use of synthetic food dyes. The Fruit Punch flavor, for example, contains Red 40. Research has linked Red 40 to kidney, stomach, and lung effects in animal studies, along with allergenic activity. Broader reviews of synthetic food colorings have documented cytotoxic and mutagenic potential across several common dyes.
These concerns aren’t unique to keto, but they matter to people following a “clean keto” approach that emphasizes food quality alongside macronutrient targets. If that’s your priority, MiO doesn’t fit the framework regardless of its carb count.
Better Alternatives for Keto
If you want flavored water without the metabolic question marks, a few options avoid the issues entirely:
- Fresh citrus slices or cucumber: A few thin slices of lemon or cucumber in a water pitcher add flavor with negligible carbs and none of the artificial additives.
- Sparkling water: Unsweetened sparkling water with natural fruit essence (no sweeteners added) satisfies the craving for something other than plain water.
- Water enhancers sweetened with stevia or monk fruit: These sweeteners have shown less impact on insulin response in research compared to sucralose.
- Herbal tea: Hot or iced, unsweetened herbal teas come in dozens of flavors and contain zero carbs with no artificial ingredients.
MiO won’t wreck your keto diet in small amounts. It has zero carbs and zero calories, and for many people that’s the only test that matters. But if you’re chasing optimal ketone levels or you’re sensitive to insulin fluctuations, the sweeteners and organic acids in MiO introduce low-grade headwinds that better alternatives simply don’t have.