You don't need to study a packet like a contract. Three numbers and one rule cover ninety percent of decisions — twenty seconds, tops.
The three numbers
Fibre per 100g — 3g is decent, 6g+ is great. Fibre is the single most under-eaten nutrient in the UK, and this number quietly separates real wholegrain products from beige marketing.
Sugar per 100g — glance at it in context: 5g in a yoghurt is nothing like 5g in a sauce you'll eat 200g of. Over 22.5g/100g counts as high.
Protein per portion — if a product sells itself on protein, check the portion actually delivers a meaningful amount (15–20g+), not a rounding error.
The one ingredient rule
Read the first three ingredients — they're listed by weight, so they ARE the product. If sugar (or one of its aliases: glucose syrup, honey, fruit concentrate) sits in the top three of something that isn't dessert, that's the packet telling on itself.
Everything else — the sunbursts, the 'high in', the 'no nasties' — is marketing. Front of pack is an advert; the back is the truth. Twenty seconds on the back beats any amount of trust in the front.
