Standing in the supermarket aisle, turning a packet over to check the label, then putting it back because the numbers don't quite make sense — if that sounds familiar, you're in good company. Food labels pack a lot of information into a small space, using terms that aren't always intuitive, and in my consultations it's one of the skills clients tell me makes the biggest everyday difference once they've got the hang of it. Understanding what you're looking at turns label-reading from a source of confusion into a quick, confident habit.
Front-of-Pack Traffic Lights
Most UK packaged foods carry a front-of-pack traffic light label showing fat, saturated fat, sugars, and salt as red, amber, or green per portion. This is designed as a quick at-a-glance check: more greens generally means a healthier everyday choice, while a food with several reds is worth having less often or in smaller amounts, rather than being off-limits entirely. It's a useful starting point, especially for a fast supermarket comparison between similar products, but it's worth remembering it doesn't tell the whole story — a food can be low in sugar and salt but still offer very little nutritional value, so it's not a substitute for looking at the fuller nutrition label when it matters.
Understanding the Nutrition Table
The nutrition table gives more detail, usually per 100g and per portion, covering energy, fat (and saturates), carbohydrates (and sugars), fibre, protein, and salt. A few habits make this genuinely useful:
- Check the serving size first — figures "per portion" only apply if you actually eat that amount, and pack servings are sometimes smaller than what people realistically eat
- Use the "per 100g" column to compare similar products fairly, regardless of pack size
- Look at the %RI (reference intake) figures as a rough guide to how a food fits into a typical day, not a strict daily budget
- Pay particular attention to saturated fat, sugars, and salt if you're managing your intake of any of these for health reasons
For clients focused on weight management, I often start here — not to obsess over every number, but to build a general feel for which everyday foods are more or less energy-dense, so decisions become quicker and more intuitive over time.
Reading the Ingredients List
Ingredients are listed by weight, from most to least, so the first two or three items tell you most of what you need to know about what a product actually is. A long ingredients list isn't automatically bad, but it's worth a glance for allergens, and for how far down the list sugar, salt, or fat-based ingredients sit — a savoury product with sugar in the top few ingredients, for example, is worth a second look.
Spotting Sugar and Salt in Disguise
Added sugars go by many names beyond the obvious ones — honey, agave nectar, maple syrup, fruit juice concentrate, dextrose, and maltose all count as sugars on an ingredients list, even when they sound more "natural." Salt is often listed as sodium; as a rough conversion, sodium content multiplied by 2.5 gives you an approximate salt figure, which is the number most people find easier to interpret against daily guidelines. Being aware of these disguises helps you make a fairer comparison between products that might otherwise look similar at a glance.
Labels and Specific Health Goals
Food labels become particularly useful once you have a specific reason to watch a nutrient closely. For clients managing blood glucose, I often talk through total carbohydrate and fibre content together, as fibre can influence how quickly sugars are absorbed — though I'd always recommend discussing any specific dietary changes for diagnosed diabetes with your GP or a registered dietitian, who can factor in your medication and monitoring. Similarly, for clients navigating menopause, checking calcium and vitamin D content on dairy and fortified alternatives is a small habit that supports bone health over time.
Practical Tips for Everyday Shopping
A few habits I recommend to clients to make label-reading faster and less overwhelming:
- Pick two or three similar products and compare the "per 100g" figures side by side rather than trying to memorise numbers
- Don't aim to read every label on every shop — focus on foods you buy regularly, since getting those right has the biggest cumulative impact
- Use the traffic light system for a quick first pass, then check the full nutrition table for anything close to a final decision
- Remember that "healthy-sounding" claims on the front of pack (like "natural" or "low fat") aren't regulated as strictly as the nutrition table itself — the table is always the more reliable source
A Worked Example
Say you're comparing two granola bars. One shows 18g sugar per 100g and red on the sugar traffic light, the other shows 6g sugar per 100g and green — but check the ingredients, and the "healthier-looking" bar might list several sugar aliases stacked near the top, with a smaller portion size than you'd naturally eat, meaning the per-portion figures look better than the per-100g reality. This is exactly the kind of comparison where taking thirty seconds with the full label, rather than trusting a front-of-pack claim alone, pays off. In my practice, I encourage clients to practise this kind of side-by-side comparison a handful of times on foods they buy often — it builds the pattern-recognition that makes future decisions much quicker.
Building Confidence Over Time
Label literacy is a genuinely learnable skill, and it gets faster with practice — most of my clients tell me that within a few weeks of consciously checking labels, they've internalised roughly what to look for and no longer need to stop and study every packet. That confidence tends to translate into calmer, more informed shopping trips generally, which is often the real goal behind wanting to understand labels in the first place.
If you'd like personalised support making sense of your everyday food choices, I offer one-to-one online consultations as a registered nutritionist. View my consultation packages or book a free discovery call to discuss how I can help.