How to read a nutrition label in ten seconds

A nutrition label contains about twelve numbers and you need two of them. Learning which two takes a minute and removes most of the ways packaged food gets logged wrong.

Go straight to the per-100g column

Every label has at least two columns: per serving and per 100 g. The per-serving column is the one designed to look reasonable. The per-100g column is the one that tells you something.

Two reasons. It is comparable — you can hold two packets side by side and know which is denser in calories. And it is not shaped by a serving size someone chose for marketing reasons.

If a label gives only per-serving figures, find the serving weight before you believe anything. If it does not state one, the label is not usable.

Then multiply by what you will actually eat

This is the step that catches everyone. A 200 g packet of namkeen with a 30 g serving contains nearly seven servings. The per-serving figure of 160 kcal looks fine; the packet is 1,070 kcal.

Nobody eats a thirtieth of a packet. Do the multiplication once, before opening it, and you will make a genuinely informed decision rather than a flattered one.

The same trap appears on drinks sold in 500 ml bottles with 250 ml serving sizes, on biscuit packets, and on anything designed to be finished in one sitting.

Know how much the number is allowed to be wrong

Food labelling regulations in most jurisdictions permit a difference between the declared value and the measured one. For energy, that tolerance is commonly around 20 per cent.

This is not fraud. Agricultural products vary batch to batch, and requiring exactness would require the impossible. But it does mean a 200 kcal bar might genuinely be 230, and a whole day logged from labels carries that margin.

It is one more reason a log is an index rather than a measurement, which is the argument in how accurate are calorie counts, really.

The lines worth a glance

Energy. Given in kilojoules and kilocalories. The kcal figure is the one everyone means.

Fat, of which saturates. Useful for judging what kind of product this is. High total fat with high saturates usually means a fried or baked item.

Carbohydrate, of which sugars. The "of which sugars" line includes naturally occurring sugars, so plain milk and plain curd look sugary and are not. What matters is whether sugar appears high in the ingredients list.

Fibre. Frequently the difference between a filling product and an empty one at the same calorie count. See fibre, fullness, and the macro nobody counts.

Protein. The line that decides whether a snack is a snack or just calories.

Salt or sodium. Not a calorie issue, but a large factor in overnight scale movement, which is covered in why the scale went up overnight when you did nothing.

Read the ingredients list for what the panel hides

Ingredients are listed in descending order by weight. That single rule tells you most of what a marketing claim is concealing.

If sugar, or any of its aliases — glucose syrup, invert sugar, fruit juice concentrate, maltodextrin — appears in the first three items, the product is substantially sugar regardless of what the front says.

If the list runs to thirty items, most of them unfamiliar, that is not automatically bad, but it does tell you the product was engineered rather than assembled.

Four front-of-pack claims that mean nothing useful

"Light" or "lite". Usually means reduced in one nutrient relative to the standard version of the same product. Light olive oil is lighter in colour and identical in calories.

"No added sugar". No sugar added during manufacture. Says nothing about the sugar already present.

"Natural". Largely unregulated in most markets. Carries no nutritional meaning.

"High in protein". Often true and often irrelevant, because the product may also be high in everything else. Check grams of protein per 100 kcal rather than per serving.

The labels you will never get

Here is the limit of all of this. Most of what most people eat has no label: home cooking, restaurant food, anything bought loose, anything cooked fresh.

Label literacy helps with the packaged fraction of your diet, which for many people is the smaller fraction. The larger one needs the methods in how to count calories in home-cooked food, and no amount of skill at reading panels substitutes for it.

Two products, same shelf, different answers

A worked comparison shows why the per-100g column earns its place.

Packet A: 480 kcal per 100 g, 8 g protein, 2 g fibre, sugar second in the ingredients list, 200 g pack. Packet B: 410 kcal per 100 g, 22 g protein, 9 g fibre, sugar seventh, 60 g pack.

Per serving, the labels might look similar, because A declares a 25 g serving and B declares a 60 g one. Per 100 g, A is denser in calories, poorer in protein and fibre, and mostly sugar. Per pack, A is 960 kcal and B is 246.

Nothing on the front of either packet tells you this. The panel does, in about ten seconds, once you know which column to read.

Bulk grains, flours and things sold loose

Loose staples — atta, rice, dal, oats, sugar — often carry no panel at all, or a minimal one printed on a sack.

For these, use a national food composition table rather than the packet. Raw ingredients are the one category where published reference values are genuinely reliable, because a lentil is a lentil regardless of who bagged it. That is what IFCT or USDA: which numbers should you trust is about, and it is why weighing staples raw is the most accurate logging you will ever do.

The ten-second routine

Per 100 g, multiply by pack weight, glance at protein and fibre, check whether sugar is in the first three ingredients. That is the whole thing, and it is enough to make packaged food a solved problem in your log rather than a recurring question.