It has become the ultimate middle-class healthy-eating flex: swapping a mass-produced, plastic-wrapped supermarket loaf for an artisan boule from a posh bakery like Gail’s.
Opt for a wholemeal version – preferably topped with an aesthetic sprinkling of seeds – and you’ve hit the nutrition jackpot (for £5 a pop), we’re told by diet gurus.
The cheap, packaged option on supermarket shelves, on the other hand, is supposedly full of harmful nasties like emulsifiers and flavourings, and is stripped of its nutrients.
TV doctor Chris van Tulleken, author of Ultra-Processed People, has referred to bog-standard loaves as ‘industrially produced edible substances’.
But is a supermarket wholemeal loaf really such a nutritional villain? And is there any benefit to paying four times the price for the freshly baked alternative?
First, it’s important to understand exactly what wholemeal means.
In the UK, ‘wholemeal’ has a strict legal definition. The flour must contain all parts of the grain—the fibre-rich outer bran, the nutrient-packed germ, and the starchy endosperm.
Don’t be fooled by ‘wholegrain’ or ‘multigrain’ options; loaves with that description are not required to be made entirely from wholemeal flour and may contain significant amounts of white flour (meaning they lack fibre and key vitamins).
Trendy bakeries like Gail’s charge £5 for a loaf of crusty bread, but is it worth it?
Modern loaves bear little resemblance to traditional bread and are often packed with ultra-processed ingredients, experts have suggested
All industrially produced bread is made using the Chorleywood process. Developed in 1961, it uses powerful mechanical mixers and Vitamin C to develop dough rapidly, reducing traditional multi-hour fermentation to just a few minutes.
The process made for pillow-soft, sliced bread that supermarkets could sell at incredibly cheap prices.
Nowadays, manufacturers often add additives to slow mould growth and emulsifiers to keep the texture soft and prevent crumbling. These are usually listed as calcium propionate, DATEM and diglycerides of fatty acids on the label.
A freshly baked loaf from a high street bakery, however, doesn’t usually carry an ingredients list – manufacturers are not legally required to provide one.
This means shoppers are generally in the dark about grain type, calorie, fibre, and salt content.
Is wholemeal bread healthier than white?
In short, yes. Two medium slices of standard supermarket wholemeal bread will provide roughly the same calories and sugar as white, but around 5.6g of bowel-friendly fibre—the same amount of white bread typically delivers 2.3g.
Health chiefs recommend that UK adults consume 30g of fibre daily, yet the average person in the UK currently manages less than 20g.
Fibre feeds beneficial gut bacteria, helps keep us full, and protects health. A 2019 review published in The Lancet found people eating around 25–29g fibre daily had a 15–30 per cent lower risk of premature death, heart disease, stroke, type 2 diabetes, and bowel cancer than those eating the least fibre.
Wholemeal bread also naturally outclasses white bread when it comes to many essential micronutrients that help release energy and keep the immune system healthy.
It contains nearly three times the magnesium, twice the zinc, and 50 per cent more iron than sliced white.
White bread isn’t entirely devoid of nutrients, though.
Under UK law, all non-wholemeal wheat flour must be fortified with calcium, iron, thiamin, and niacin to restore some of what was stripped away during milling—with folic acid about to join the mandatory list. These additions feature in both a budget white sliced loaf as well as an expensive, artisan one.
Is supermarket bread healthy?
Yes but unfortunately, the more expensive, fresh version is likely to be healthier.
Firstly, the additives in supermarket-bought bread are a potential hazard. Some laboratory and animal studies suggest the compounds might disrupt the protective mucus lining of our gut, or alter the microbiome.
Dr Megan Rossi, a research fellow at King’s College London, has just finished working on the world’s first clinical trial investigating a low-emulsifier diet in humans, looking at patients with Crohn’s disease, an inflammatory bowel condition.
‘For the first time, we showed that following a low-emulsifier diet not only improved symptoms but also reduced disease severity,’ says Dr Rossi.
But she adds that the evidence of harm isn’t yet certain for those without bowel conditions.
‘Having a slice or two of bread containing these emulsifiers isn’t something I’d consider concerning in isolation.’
However the health risk lies with the fact roughly half of all ultra-processed foods contain at least one emulsifier – and Britons eat a lot of them.
‘If someone is eating multiple foods containing emulsifiers throughout the day – breads, baked goods, plant milks, desserts, snack bars and other ultra-processed foods – then the cumulative intake may become more relevant,’ Dr Rossi explains.
Opting for a wholemeal sourdough can boost the health properties – and even better if it’s fresh, without potentially harmful additives.
The slow, multi-hour fermentation partially breaks down some wheat proteins, which some people find makes it gentler on the gut.
The acids produced during fermentation also delay stomach emptying, helping steady blood sugar and keeping you fuller for longer.
Furthermore, fermentation neutralises phytic acid—a compound that binds to minerals—which may improve how well your body absorbs the bread’s iron, zinc, and magnesium.
But the posh sourdough loaf only triumphs if it’s made with wholemeal flour. Many sourdough loaves sold in trendy high-street chains like Gail’s are made using white flour and contain far less fibre than a standard, budget supermarket wholemeal loaf.
Rye bread is another excellent option, but bakeries often blend it with white wheat flour to keep the loaf light and fluffy, diluting its high-fibre benefits.
If I have to buy bread at the supermarket, which loaf should I choose?
If you want a wholemeal loaf without emulsifiers and preservatives you don’t have to spend a fortune.
Supermarkets have begun quietly offering ‘cleaner-label’ packaged bread. For example, Marks & Spencer’s Super Soft Wholemeal does not contain the preservative calcium propionate or DATEM and costs just 75p.
Other examples of low-additive or additive-free products include Tesco Finest Wholemeal (£1.50), ASDA The Bakery Sliced Wholemeal Tin Loaf (£1.56) and Sainsbury’s Taste the Difference Soft Multiseed Farmhouse Wholemeal (£1.60).
It’s true that bread is often a dieter’s biggest downfall. But this is as a result of what is put on the bread, rather than the type of flour someone chooses.
In other words, there’s no point selecting a pricey wholemeal sourdough if you’re planning to use it to make a daily bacon, egg and cheese sandwich.
Keep your toppings as varied as possible, with a balance of protein, vegetables and a little healthy fat, and you’ll have yourself a gold-standard lunch.
