Not all processing is bad. Technically speaking, even oats that have been rolled or porridge that's been cooked is 'processed'. The issue isn't processing itself - it's the degree of it.

The most widely used framework for categorising food by its level of processing is called the NOVA classification system, developed by researchers at the University of São Paulo. It groups foods into four categories:

• Unprocessed or minimally processed foods i.e. whole foods close to their natural state, such as oats, nuts, seeds, fruit and vegetables.
• Processed culinary ingredients i.e. things like oils, salt, and sugar used in cooking.
• Processed foods i.e. foods that have been preserved, fermented, or otherwise altered (think cheese, tinned fish, or bread).

• Ultra-processed foods (UPFs) i.e. industrially manufactured products made largely from extracts of food, often combined with additives, emulsifiers, colourings, sweeteners, and flavourings that you wouldn't find in any home kitchen.

It's that final category, ultra-processed foods, that researchers are increasingly focused on, and that many common breakfast cereals and cereal bars fall squarely into.

Breakfast sets up your energy, hunger, and blood sugar levels for the rest of the morning. What you eat first thing has a real downstream effect on how you feel, how focused you are, and how satisfied you stay before lunch.

Ultra-processed breakfast foods tend to be energy-dense but low in fibre, with high amounts of added sugar, salt, and refined carbohydrates. These can cause a rapid spike in blood sugar followed by a crash, leaving you hungry again within a couple of hours, even if you ate a large portion.In contrast, natural breakfast options built around whole ingredients e.g., wholegrain oats, nuts, seeds, and fruit, digest more slowly, provide sustained energy, and tend to be far richer in fibre, vitamins, and minerals.

Studies have found that adults in the UK get, on average, 54%* of their daily calories from ultra-processed foods, with breakfast cereals frequently cited as one of the biggest contributors.

The evidence against a diet high in UPFs has grown substantially over the past few years. A 2024 review of 45 meta-analyses, covering nearly 10 million study participants, found convincing evidence that diets high in ultra-processed foods are associated with significantly increased risks of cardiovascular disease and anxiety. The review was covered by Stanford Medicine.

Separately, research published in the journal Nature Medicine in 2025 compared participants on a minimally processed diet against those eating processed foods meeting UK nutritional guidelines and found that the minimally processed group lost more body fat, experienced fewer cravings, and showed markers associated with better heart health.

It's worth noting that not all ultra-processed foods carry the same level of risk; the NOVA classification is broad, and context matters. But the breakfast aisle is a particularly important space to scrutinise, because many products marketed as 'healthy' are, by NOVA criteria, ultra-processed.

*Proceedings of the Nutrition Society / University of Cambridge research, published via TableDebates.

Wholegrain oats are one of the most researched breakfast foods in the world, and the evidence for them is consistently positive.

They're a rich source of beta-glucan, a soluble fibre shown to help maintain healthy cholesterol levels, support stable blood sugar, and keep you feeling fuller for longer. But perhaps most interestingly, oats have a growing body of evidence around gut health.

A review published in Nutrients (2023) found that oat consumption is associated with increased levels of Lactobacillus, Bifidobacterium, and Akkermansia - beneficial bacteria linked to reduced inflammation, better lipid metabolism, and a healthier gut lining. The fibre in oats acts as a prebiotic, feeding and supporting the good bacteria in your gut.

Research published in the Nutrition Bulletin (Wiley, 2018) also highlighted that wholegrain oats may help support cardiovascular health through their interaction with the gut microbiota, producing short-chain fatty acids that appear to inhibit cholesterol synthesis in the liver.

In short: a breakfast built around wholegrain oats isn't just filling, it's actively doing something useful for your body.

You don't need to become an expert in food science to make better choices. A few simple habits make a real difference.

1. Start with the ingredients list, not the front of pack: Front-of-pack claims like 'natural', 'wholesome', and 'high in fibre' are marketing language, not regulated nutritional facts. The real story is in the ingredients list on the back. Ingredients are listed in descending order by weight - so whatever appears first is the main ingredient.

2. Count the ingredients: This isn't a hard and fast rule, but as a quick gut check: the longer the ingredients list, the more likely you're looking at a heavily processed product. Whole foods have short lists. Ultra-processed foods often have dozens of ingredients, many of which you wouldn't recognise.

3. Watch out for hidden sugars: Sugar hides under many names on UK labels. According to Nutrition Path UK, UK labelling regulations permit up to 60 different names for sugar - including words ending in '-ose' (like glucose, dextrose, maltose), syrups, nectars, and fruit juice concentrates. If multiple forms of sugar appear in the ingredients list, the total sugar content is likely higher than it looks.

4. 'Gluten-free' doesn't automatically mean natural: A gluten-free label tells you what isn't in the product - it says nothing about what is. Many gluten-free breakfast cereals are still ultra-processed, and some compensate for the removal of gluten with additional sugar or fat to improve texture and taste. Always check the full ingredients list, not just the front-of-pack claim.

5. Check the fibre content: Most UK adults consume around 18g of fibre per day - well below the recommended 30g. A good natural breakfast is one that starts to close that gap. Look for products with 6g or more of fibre per 100g; this is the threshold for a 'high fibre' claim under UK food labelling regulations.