How to Read Nutrition Labels Like a Pro

You pick up a snack bar, flip it over, stare at the nutrition panel for five seconds, and put it back. Sound familiar? Nutrition labels are legally required to contain a lot of information — but that doesn't mean they're designed to be easy to read.

Start with the serving size — always

Everything on the label — calories, fat, sugar, sodium — is based on the stated serving size, not the whole package. A bag of crisps might list 130 calories, but if the serving size is 30g and the bag contains 90g, you'd eat 390 calories if you finish it.

Manufacturers can legally set whatever serving size they like. A common trick is setting it lower than what a person would typically eat, making the numbers look more appealing. Always check how many servings are in the package.

Calories: necessary but insufficient

Calories (kcal) tell you how much energy a food delivers, but not the quality of that energy. 200 calories from almonds and 200 calories from jelly sweets have completely different effects on your body, satiety, blood sugar, and nutrient intake.

Use calories as a rough guide for overall energy balance, but look at the full macro and ingredient picture before deciding.

Fat: total vs. saturated vs. trans

Not all fat is the same. The label will show total fat, then break it into saturated and (sometimes) trans fats. Unsaturated fats — the ones not listed separately — are generally considered beneficial for heart health.

• Saturated fat: Found in butter, red meat, coconut oil. Aim to limit — most guidelines suggest under 20g/day for adults.
• Trans fat: Artificially hydrogenated — avoid entirely if possible. Any amount above 0g is undesirable.

Sugar: total vs. added

Labels show total sugars — which includes naturally occurring sugars (like lactose in milk or fructose in fruit) alongside added sugars. Both affect your blood glucose, but added sugars in ultra-processed foods tend to be paired with low fibre, which removes the buffer that slows absorption.

Many labels now show "of which added sugars" separately — pay attention to this line. The WHO recommends keeping free (added) sugars below 10% of total daily energy, ideally under 5%.

Fibre: the underrated hero

Most people eat far less fibre than recommended (25–30g/day). Fibre slows digestion, feeds gut bacteria, stabilises blood sugar, and promotes satiety. When comparing products — especially breads, cereals, and snacks — more fibre is almost always better.

Aim for products with at least 3g of fibre per 100g.

Salt (sodium): the silent one

Salt (sodium chloride) is often hidden in seemingly savoury-and-sweet products — bread, cereals, sauces. Labels in the EU/UK show salt; US labels show sodium (multiply by 2.5 to convert to salt equivalent).

The recommended daily limit is under 6g of salt (2.4g sodium). A single portion of some ready meals can exceed that on its own.

The ingredient list: read it backwards

Ingredients are listed by weight, descending. The first few ingredients make up the bulk of the product. If sugar, palm oil, or white flour appears in the first three, that's what the product mostly is.

A general rule: if you can't pronounce more than two or three ingredients, or the list is longer than a paragraph, you're probably looking at a heavily processed food.

ShelfIQ surfaces all of these numbers automatically when you scan a product. The AI health score factors in your personal dietary restrictions and compares the product against these benchmarks — so you don't have to do the maths in the aisle.