Quick answer: Keto is a tightly defined version of low-carb — usually under about 50g of carbs a day with around 70 to 75% of calories from fat, low enough to push the body into ketosis. Low-carb is the broader umbrella, generally taken to mean under about 130g of carbs a day, with no requirement to reach ketosis. We do not tell you which one to follow. We are a UK food tracker — set whatever carb target you have chosen and we make logging it easy.
What "keto" actually means
The ketogenic diet sits at the strictest end of the carb-restriction spectrum. The defining feature is not the food list — it is the metabolic state called ketosis, where the body, starved of glucose from carbs, shifts to burning fat and producing ketones for fuel.
To get there and stay there, most versions of keto target under 50g of carbohydrate per day, with a typical macro split of roughly 70 to 75% fat, 20 to 25% protein, and 5 to 10% carbohydrate. That is a hard ceiling — a single medium banana puts you near the daily carb limit on its own.
Foods that fit a keto diet: meat, fish, eggs, full-fat dairy, most non-starchy vegetables (leafy greens, courgettes, peppers, broccoli, cauliflower), nuts, seeds, olive oil, avocado, butter. Foods that effectively do not: bread, rice, pasta, potatoes, most fruit, sugary drinks, beans and pulses, and most processed snacks. The line is drawn by carb count per portion, not by food group, but it works out the same in practice.
Keto requires careful tracking — small amounts of hidden carbohydrate in sauces, condiments and packaged foods can take you out of ketosis without you realising. That is why people on keto tend to scan everything.
What "low-carb" actually means
Low-carb is a much looser umbrella term. There is no single agreed definition, but it is commonly taken to mean under about 130g of carbs per day — well below the typical UK average. Some people call 100g/day low-carb; others go to 80g; some sit nearer 50g without aiming for ketosis at all. The NHS uses "low-carb" loosely to describe any approach below typical intake.
Crucially, low-carb does not require ketosis. You can sit at 100g of carbs a day, still burn glucose for some of your energy, and call yourself low-carb. There is no fixed fat target either — protein is often a bigger share of the plate than on keto.
Foods that fit low-carb: everything keto allows, plus moderate portions of berries and other fruit, small amounts of pulses and beans, occasional whole grains in measured portions, and root vegetables in smaller servings. The diet allows more day-to-day flexibility — a piece of fruit at lunch, a smaller portion of rice with a curry, a slice of sourdough — without breaking the approach.
The practical difference in one sentence
Both diets reduce carbohydrate compared with a typical UK diet, which the UK National Diet and Nutrition Survey records as around 215 to 250g of carbohydrate per day for adults. Low-carb cuts that down to around 100 to 130g; keto cuts it harder, to 50g or less, and adds the ketosis requirement on top. Keto is a specific, regimented version of low-carb; low-carb is the wider category.
At a glance
| Factor | Keto | Low-carb |
|---|---|---|
| Daily carbs (typical) | Under 50g | Under ~130g (varies) |
| Ketosis required? | Yes — that is the point | No |
| Fat (% of calories) | ~70 to 75% | No fixed target |
| Protein (% of calories) | ~20 to 25% | Often higher than keto |
| Fruit | Berries only, in small portions | Moderate portions |
| Bread, rice, pasta, potatoes | Effectively excluded | Smaller portions |
| Day-to-day flexibility | Tightly defined | Looser umbrella |
| How much tracking needed | Most foods, every day | Lighter — track to stay under target |
What UK health bodies say (factually)
The UK position is worth being careful about. We are not a medical service, so what follows is what the official bodies have published — not what we think you should do.
The NHS does not recommend any specific macro split for the general adult population. Its general dietary guidance is the Eatwell Guide, which describes a balanced pattern of starchy carbohydrates (preferably wholegrain), fruit and vegetables, protein, dairy or alternatives, and unsaturated oils. That is its population-level guidance — not a directive against keto or low-carb.
NICE (the National Institute for Health and Care Excellence) has reviewed lower-carbohydrate approaches as one option for adults managing type 2 diabetes. Clinically supervised low-carb programmes have shown positive evidence in this group for some people. NICE positions it as an option to discuss with a clinician, alongside other approaches — not a blanket recommendation.
What the regulators do not currently do is endorse keto as a general weight-loss diet for the population. Strict ketogenic diets remain a clinical tool used in specific medical contexts under supervision.
Bottom line: if you are considering either diet — especially if you take medication, are pregnant, have type 1 or type 2 diabetes, or have a history of disordered eating — speak to your GP or a registered dietitian first. We are a tracking app. They are the people who know your medical history.
How to track either diet with NutraSafe
Whichever target you (or your clinician) have chosen, the practical job is the same: keep a running total of carbs through the day so you know whether you are over or under. We make that part easy.
- Set your daily carb target. Whatever number you have picked — 30g for strict keto, 80g for moderate low-carb, 130g for the looser end — go into your macro settings and set it. We track the running total against it for the day and the week.
- Scan UK barcodes. We read any UK GTIN/EAN — the same barcode format used in every UK supermarket. The card you see on a scan shows ingredients, additives we found, and the carbs, protein and fat per portion as printed on the back of the pack. Hit log, pick a portion, and your daily totals update.
- Search by name for unbranded foods. Apples, an egg, a banana — type the name, pick a portion, the macros come from the same UK nutrition data we use for packaged products.
- Photograph the plate (NutraSafe Pro). For a takeaway or someone else's cooking, our AI meal scan estimates carbs and the rest of the macros from a photo. Less precise than a barcode, more honest than guessing.
- Track vitamins and minerals against UK NRVs (NutraSafe Pro). This matters more than usual on keto and low-carb. Cutting fruit, starchy veg, grains and pulses can leave gaps in fibre, folate, vitamin C, magnesium and potassium — all common on these diets. We run every food you log through our micronutrient engine and show you, week by week, where you are sitting against UK Nutrient Reference Values. Those are the same numbers you see on the back of every UK pack — so a label that says "30% NRV vitamin C" lines up with the figure on your dashboard.
What we will not do: tell you which diet to follow, declare a winner, or pass judgement on a day's logs. There are no grades on user food, no green ticks, no verdict pills. Just your numbers, against the target you have chosen, against UK reference values.
What you get free, and what is on NutraSafe Pro
Our app is free to download. The full feature set is paid. Here is the split, taken straight from the code.
Free
- Log up to 25 foods per day with full carb, protein and fat tracking — enough for most people most days.
- Scan any UK barcode for ingredients, additives we found, and our per-product grade.
- Log up to 5 reactions against foods.
- Public E-number lookup — type any E-number, see what it is in plain English.
- No ads, ever.
NutraSafe Pro — £3.99/month (iOS, monthly only)
- Vitamin and mineral tracking against UK Nutrient Reference Values across your full diet — particularly useful on keto and low-carb where food groups get cut.
- AI Coach — chat-style guidance based on your actual food history and goals.
- AI meal scan — photograph any plate for an estimated calorie and macro breakdown.
- Allergen warning detail on barcode scans.
- Fasting tools and workouts tracking.
- Suspected-triggers analysis — we surface foods that show up repeatedly before reactions.
- Processed-food and NRV insights — week-on-week trends for the metrics that matter.
No annual plan, no free trials with hidden charges. £3.99 a month, monthly, on iOS, cancel from the App Store any time.
Before you start either diet
Speak to your GP or a registered dietitian first
Both keto and low-carb cut whole food groups and change how your body uses fuel. That matters more if you take medication (especially for diabetes or blood pressure), are pregnant or breastfeeding, have a history of disordered eating, or have any chronic condition. We are a tracking tool — the conversation about whether either diet suits your medical situation belongs with a qualified clinician, not an app.
For more on each approach individually, read our dedicated guides: keto diet UK guide and low-carb diet UK guide. If you are interested in tracking the macro picture more generally, our macro tracker UK page walks through carbs, protein and fat in plain English. For broader UK food-pattern context, the calorie counter UK guide covers the energy side.