I'm a nutritionist - here's the healthiest cereals on your supermarket shelf and the ones to always avoid

Published: 11:33, 28 July 2026 | Updated: 12:10, 28 July 2026 A decade ago, a nutritious start to the day seemed simple – you couldn't go wrong with a bowl of relatively boring cereal.  Whether muesli, Weetabix or Cornflakes, you could be sure you were getting at least some goodness.  But today, the cereals on our supermarket shelves have become a new nutrition villain, with diet gurus and weight loss experts urging Britons to avoid the 'sugar filled' products.  According to diet book author Professor Tim Spector, breakfast cereal is 'fake food made in factories that contain none of the original nutrients from plants'. The scientist has also claimed that 'virtually no breakfast cereal is good for you'. As a nutritionist with more than a decade of experience, I can tell you he is wrong. Many cheap options on our supermarket shelves are in fact a perfectly sound choice, with practically no sugar and delivering a good boost of fibre to help prevent bowel disease, including cancer. But some products claiming to be 'healthy' are better than others – and it can be difficult to spot red flags, for instance a short ingredient list isn't necessarily a good thing. Here, we compare some of Britain’s best‑known 'healthy' cereals. We've analysed a 100g portion – as opposed to the 30g listed on the back of the packet – because that's far more representative of a typical bowl. How does your favourite fare? M&S 'three ingredient' products are marketed as a kick-back against ultraprocessed food Contains: 367 calories, 0.4g fat, 2.1g sugars, 10.9g fibre, 11.2g protein, 0.88g salt Made from just wholegrain wheat, barley malt extract and salt, these minimal-ingredient bran flakes lean into the non-UPF trend but are somewhat lower in fibre than the popular Kellogg’s version – although they still deliver a third of your recommended daily intake. Barley malt extract, produced from sprouted barley and used as a sweetener, is used very sparingly (the equivalent of just half a teaspoon), so it’s a low‑sugar option. The downsides are they are unfortified with essential vitamins like other products, and are slightly saltier.  The wheat biscuits are a common choice for Britons looking for a nutritious start to the day Contains: 362 calories, 0.6g fat, 4.2g sugars, 10g fibre, 12g protein, 0.28g salt With 95 per cent wholegrain wheat and added vitamins and minerals, a couple of Weetabix with protein-heavy milk is hard to fault. It's a good source of fibre and protein, and low in sugar – most of which comes from malted barley extract – and salt. While studies show most people eat 60-100g at breakfast, this would equal roughly four biscuits, which is quite a bit. Therefore it's likely the average person will consume fewer calories and sugar than is listed above. This makes it one of the most nutritious breakfast cereals and perhaps the best family all-rounder.  Shredded Wheat is 'hard to beat', according to nutritionist Angela Dowden Contains: 363 calories, 0.5g fat, 0.8g sugars, 14.3g fibre, 12.5g protein, 0.05g salt If you value simplicity above all else, Shredded Wheat is hard to beat. Made entirely from wholegrain wheat, it's naturally high in fibre and protein while containing virtually no sugar or salt. It isn't fortified, so you miss out on some useful added vitamins and minerals but with milk and some berries it's a healthy start to the day.  This puffed wheat contains the least amount of sugar and salt of all the cereals analysed Contains: 362 calories, 0.8g fat, <0.5g sugars, 8.3g fibre, 10.5g protein, trace salt Containing nothing more than steam-puffed wheat, this cereal is the least sugary and salty of all the products.  A big bowl provides a decent amount of protein – but not as much bowel-friendly fibre as Weetabix, Bran Flakes and Shredded Wheat. It also isn't fortified, meaning it's not quite the nutritional all-rounder that Weetabix is. But with milk and a fruit and seed topping it's still a healthful choice. A good hit of fibre and protein in Shreddies, but the sugar content tips the cereal into unhealthy Contains: 365 calories, 0.3g fat, 12.5g sugars, 12g fibre, 10.8g protein, 0.73g salt Made from more than 96 per cent wholegrain wheat, Shreddies offers more than a third of your daily fibre and enough protein to keep you full, with the added benefit of iron and B vitamins.  The sugar content is higher than ideal – around three teaspoons in a large bowl – but they’re still a far better everyday choice than many people assume.  Those who are prone to a sluggish digestive system could benefit from All Bran Contains: 313 calories, 0.5g fat, 15g sugars, 26g fibre, 12g protein, 0.9g salt If fibre is your priority, few cereals come close. Nearly 80 per cent wheat bran, it delivers almost the entirety of your daily fibre needs in one large bowl. Wheat bran is one of the best-studied fibres for moving food along the gut, making this a particularly good choice if you're prone to constipation. It also provides useful iron and B vitamins though the trade‑off is that the recommended serving contains around 15 per cent of your daily salt.  This pricey oat-based cereal is a calorie-heavy breakfast that will keep you full, but it is sugary Contains: 403 calories, 1.6g fat, 8.3g sugars, 9.8g fibre, 11.6g protein, 0.05g salt Packed with wholegrain oats, toasted wheat flakes and generous handfuls of almonds, cashews and hazelnuts, this is inevitably more calorie-dense because of the nuts, but with the minerals that nuts provide, this is of little concern. The sugar content comes naturally from raisins rather than added sugar, but is still more than is ideal at breakfast.  No added sugar doesn't mean the product is low in sugar, says nutritionist Angela Dowden Contains: 427 calories, 3.5g fat, 9.8g sugars, 18g fibre, 8.5g protein, 0.05g salt One of the better granolas on the market, made largely from wholegrain oats, seeds and dried fruit, rather than added sugar. But don't confuse 'no added sugar' with 'low sugar' – there's still more than two teaspoons' worth because of naturally occurring sugars in the fruit. Some of its impressive fibre comes from added chicory root fibre, a prebiotic that can boost the healthy bacteria in the gut. Special K is among the worst-performing cereals, despite its 'diet-friendly' reputation Contains: 392 calories, 0.3g fat, 15g sugars, 6g fibre, 8g protein, 0.84g salt Special K has moved on from its dieting‑era reputation, and has since repositioned itself as a healthy everyday cereal. It’s one of the more heavily fortified cereals, providing generous amounts of iron, vitamin D and B vitamins – the iron boost in particular is useful for women and girls who are more vulnerable to deficiency. The fibre content is on the lower end – containing half the amount of some other cereals – and the sugar level – more than three teaspoons – is higher than ideal.  The breakfast favourite doesn't live up to its fibre-friendly name Contains: 408 calories, 3g fat, 23g sugars, 8.8g fibre, 9g protein, 1.1g salt Despite the name, this cereal is considerably lower in fibre and protein than some other wholegrain cereals. Although some of its sugars come naturally from dried fruit, it also contains added sugar and has the highest total sugar content in our selection, while coconut pushes up the saturated fat.  If you're in the market for a healthy breakfast, Corn Flakes are not the ideal choice Contains: 378 calories, 0.2g fat, 8g sugars, 3g fibre, 7g protein, 1.1g salt Made from refined maize rather than wholegrain, corn flakes contain very little fibre and only modest protein, so they’re unlikely to keep you full for long. They do offer some iron and B vitamins, and their sugar content is average, but they are nutritionally inferior to most other options. Adding a handful of almonds can help slow the rise in blood sugar and make the meal more filling.