What is the glucose ketone index (GKI)?
The glucose ketone index is a single number that combines two readings: blood
glucose divided by blood ketones, both in mmol/L. It was proposed by Meidenbauer,
Mukherjee and Seyfried in 2015 as a way to track the two values together instead of
watching them separately, because either one on its own can be misleading.
The arithmetic is simple. If glucose reads 4.5 mmol/L and ketones read 1.5 mmol/L,
the GKI is 3.0. Lower numbers mean glucose is low relative to ketones.
Published work describes broad zones rather than one correct target, and which zone
is appropriate depends entirely on why a person is tracking it at all.
The step people most often get wrong is the unit. If your glucose
meter reads in mg/dL, divide by 18 before dividing by ketones. Skipping that
conversion produces a GKI roughly eighteen times too high.
KetoNoir computes GKI automatically from any glucose and ketone readings logged
close together, and charts it over time so the trend is visible rather than a
single day's number.
Net carbs or total carbs: which do you count?
Net carbs are total carbohydrate minus fiber. Most people following a ketogenic
diet count net carbs, on the reasoning that fiber is not digested into glucose the
way starch and sugar are.
The complication is that net carbs are a convention rather than a regulated
definition, and the edges are genuinely inconsistent. Fiber is subtracted almost
universally. Sugar alcohols are not: erythritol is commonly subtracted in full,
while maltitol has a measurable glucose effect, so subtracting it in full overstates
how little it counts. And outside the United States some countries already exclude
fiber from the carbohydrate figure printed on the label, which means subtracting it
again double counts.
The practical answer is to pick one convention and hold it, because what moves the
needle is the trend across weeks, not the arithmetic on any single item.
KetoNoir computes net carbs as total carbohydrate minus fiber on every food, every
recipe and every restaurant item, wherever the source data carries a fiber value.
How long does it take to get into ketosis?
For most people restricting carbohydrate, measurable blood ketones appear within
two to four days. The range is wide because it depends on how low the carbohydrate
intake actually goes, how much glycogen was stored to begin with, and how active
the person is.
Being in ketosis is a measurement, not a feeling. Blood ketone
meters read beta-hydroxybutyrate directly and are the most reliable consumer
option. Urine strips measure acetoacetate being excreted, which is why they often
stop reading strongly after the first couple of weeks even when someone is still in
ketosis. Breath meters measure acetone and sit between the two.
Whether a ketogenic diet is appropriate at all is a question for a clinician,
particularly for anyone taking medication for diabetes or blood pressure, where
dosing can need adjusting.
What is the keto flu?
The keto flu is the cluster of symptoms commonly reported during the first week of
carbohydrate restriction: headache, fatigue, irritability, muscle cramps and poor
sleep. It is not an infection, and it is not universal.
The mechanism usually described is fluid and electrolyte loss rather than the
absence of carbohydrate itself. Lower insulin leads the kidneys to excrete more
sodium, water follows the sodium out, and potassium and magnesium tend to fall
alongside it.
This is general information, not a recommendation. Sodium intake is exactly the
variable that some blood pressure and kidney conditions require to be managed
carefully, so it is worth raising with a clinician rather than adjusting alone.
Can an AI coach actually help with keto?
Only if it can see your data. A retrieval chatbot answers from general knowledge and
does not know what you ate. KetoNoir's coach reads today's food log, your recent
totals and your logged biomarkers on every turn, and it can write entries to your
diary after you confirm.
How KetoNoir's AI keto coach works
What should you compare when switching keto trackers?
Compare what you will use every day: whether the coach can write to your log or only
chat, how much history you keep, whether net carbs are their own number, whether blood
ketones and GKI have a place, how food gets in, whether your language is fully
supported, what the free tier really covers, and how your data is handled.
The switching checklist, with KetoNoir's answers
Is KetoNoir free?
Yes, with no time limit. The free tier covers unlimited manual food logging with
your full history, the full multi source food search, every KetoNoir and fatsecret
recipe, every trends chart for weight, ketones, glucose and GKI over up to 365 days,
biomarker and urine strip logging, the bilingual interface and allergen flagging.
The AI coach comes with a small daily message allowance, larger during your first 48
hours so onboarding can finish, and it can build meal plans and recipes in chat.
Barcode scanning runs at two a day.
Premium adds the Metabolic Forecast, body composition analysis, saving meal plans,
Snap a Meal photo logging, fridge ingredient scanning, recipe photo scan, Apple
Health and Health Connect sync, and higher daily limits.
Price depends on where you subscribe, because the app stores take
a cut and the web does not. Subscribing on the web is 10 percent less. Premium
Monthly is $9.99 in app or $8.99 on the web, and Premium Annual is $59.99 or $53.99.
Premium Family Annual is $89.99 in the iPhone app only, for up to 6 people in your
family through Apple Family Sharing. All three carry a 14 day free trial.
Does KetoNoir work in Spanish?
Yes, completely. The Spanish build is a full localization rather than a partial
translation, and it reaches the recipe names and cooking instructions, the AI
coach, and the legal consent screens, not just the interface labels.
The recipe catalog reflects that. 289 proprietary recipes span Latin, American,
Italian, French and Mediterranean traditions, 182 of them keto flagged. The Latin
selection alone covers 16 cuisines: Mexican, Cuban, Spanish, Brazilian,
Argentinian, Peruvian, Colombian, Venezuelan, Chilean, Bolivian, Ecuadorian,
Salvadoran, Dominican, Guatemalan, Puerto Rican and Tex-Mex.
How many foods and recipes are there?
Two separate figures, and they should not be added together.
Foods: 2.3 million or more. Generic, branded, supermarket and
restaurant items, plus menu data for 176 US chains. Nutrition data powered by
FatSecret, with USDA FoodData Central and Open Food Facts as parallel cross checks,
reconciled by a confidence resolver and an energy consistency guard that flags
entries whose macros do not reconstruct their stated calories.
Recipes: two separately sourced collections. 289 proprietary
bilingual cultural recipes, of which 182 are keto flagged, plus 3,800 or more
recipes from FatSecret's database. They sit side by side in one search field and
are never merged into a single number.
What can it track besides food?
Blood glucose, blood ketones, GKI, body weight, blood pressure and a full
cholesterol panel, entered by hand or through the coach in chat. Urine ketone strips
are logged by picking the strip's color. Blood ketones always come in by hand or
through the coach: Apple Health and Health Connect have no blood ketone reading.
With Premium it also reads from Apple Health and Health Connect: weight, blood glucose,
blood pressure, sleep, active and resting energy, steps, workouts, resting heart rate and
heart rate variability.
The two are kept apart on purpose. Weight, glucose and blood
pressure read from Health are saved to the account, because trends and coaching are
built from that history. Sleep, energy, steps, heart rate and workouts are read
only while a forecast runs and are not kept in biomarker history.
What is the Metabolic Forecast?
A 72 hour forward projection built from your own logged history rather than
population averages. It reads up to 14 days of that history and includes a 3 day
energy projection and a weight fluctuation chart drawn from real weigh ins.
It will not run until at least 3 days have been logged, and it
says so rather than guessing. Accuracy widens with logging consistency. Optional
inputs include sleep, heart rate variability, resting heart rate, VO2 max, active
energy and steps. It is a Premium feature, limited to two runs a day.