We're often advised to avoid foods like white bread, salty snacks and chocolate. But, while eating too many of these foods has been linked with heart disease and obesity, when consumed in moderation they can form part of a balanced diet. In fact, some of these supposedly ‘bad’ foods may have surprising health benefits.

Click or scroll through our gallery as we reveal the 23 nutritionist-approved ‘unhealthy’ foods that might actually do you good.

We used official food composition tables supplied by GOV.UK to compile nutritional value information for this feature. 

Following a similar train of thought, homemade oven chips made using just potatoes and oil are no more ‘processed’ than roast or mashed potatoes prepared from scratch. An average 5.3oz (150g) serving supplies 1.37mg of the 3-4mg vitamin E we need daily for a healthy immune system and also contains 0.2oz (5.3g) fibre, similar to the amount in two slices of wholemeal bread.

Yes, you read that right – some cake can actually be pretty good for you. There are enough currants and sultanas in a classic homemade fruit cake, for example, for a slice to count as one of your five-a-day. And the fruits in that same slice also provide around 10% of your recommended daily intake of fatigue-fighting iron, too. Obviously, the less sugar in the cake, the better it is for you.

While fried eggs are higher in calories than poached, eggs are rich in protein, B vitamins, vitamin D and selenium – and frying doesn’t deplete any of that goodness. Just be sure to use an unsaturated oil, like rapeseed or olive oil, in your frying pan or skillet.

If you trim off all the visible fat, unprocessed red meats like beef and lamb can be a healthy choice. "Red meat provides easily absorbed iron and plenty of zinc, which we need for a healthy reproductive system and brain function," says registered dietitian Priya Tew. To minimise the risk of colon cancer, aim to consume no more than 10.5-17.6oz (300-500g) of cooked red meat a week.

Cheese is fattening, right? In theory, yes. But in practice, studies suggest that cheese eaters often tend to be slimmer and don’t have higher cholesterol levels, despite eating more saturated fat. One theory is that cheese boosts gut-friendly bacteria that produce a compound called butyrate, which in turn improves the metabolism. Cheese is high in calcium and is also a good source of protein, so a small amount tends to keep you full for a long time.

A healthy wholemeal loaf has 0.09oz (2.8g) fibre per slice, but that doesn’t make white bread – with 0.03oz (1g) of fibre per slice – bad for you. In fact, because white flour is, by law, fortified with a range of vitamins and minerals, two slices of white bread supply around 17% of your daily requirement of calcium (about the same as a couple of generous tablespoons of Greek yogurt).

There’s more good news for those who favour sliced white for their sandwiches. While white bread has a reputation for increasing blood sugar and insulin levels at a far more rapid rate than bread made with whole-grain flour, it’s not quite as clear cut as all that. There is evidence to suggest that, for some people, standard white bread actually causes less of a sugar rush than whole-grain sourdough. It’s all down to the individual; the way your blood glucose levels react could be down to the types of bacteria present in your gut.

While for years full-fat milk was shunned by many in favour of skimmed – and skinny lattes and cappuccinos were all the rage – this mindset has shifted. Studies have found that those who consume full-fat dairy products, such as whole milk, are no more likely to develop cardiovascular diseases than those who avoid them. In addition, whole milk benefits bone health, is a good source of nutrients and is packed with protein. Some people prefer the silky, more velvety mouthfeel, too.

As well as containing polyphenols linked with improved gut health, a 6fl oz (175ml) glass of antioxidant-rich red wine – approximately two alcohol units – provides 1.6mg iron, which is just over 10% of the daily recommended intake of this anaemia-protective nutrient. Research has also found that red wine may help to lower the risk of heart disease and strokes by increasing good cholesterol levels and lowering bad ones.

Because of their high glycaemic index or GI – the measure of how quickly a carbohydrate releases sugar into the bloodstream – potatoes have often been labelled as less healthy. But that idea is well worth reconsidering. Potatoes are a good source of carbohydrates, vitamins and trace minerals, meaning they boast plenty of health benefits. Prepare them the right way (steer clear of the deep fat fryer or adding mounds of butter and cream) and there’s absolutely no reason to deny yourself the pleasure of a potato-based meal.

Cereals get a bad rap, but pick carefully and a bowl can deliver health benefits. Cheerios, for example, are fortified with at least 15% of your recommended daily intake of nine vitamins and minerals per small bowl. Add 5.3fl oz (150ml) milk and that goes up to more than 40% of the daily recommendation for calcium specifically. A serving also contains close to 10% of your daily fibre requirements, while the added sugar content isn't too bad at 0.17oz (5g) per bowl.

While would-be healthy eaters may have become accustomed to ordering their salads with the dressing on the side, make your dressing from scratch and it can add extra flavour and texture to a dish – without turning it into an unhealthy one. A classic vinaigrette, made with antioxidant-rich olive oil, vinegar and mustard, is great to have on standby in the fridge, while Greek yogurt spiked with lemon juice and plenty of black pepper is a lighter alternative to mayonnaise-based dressings.

Gooey, sticky, squidgy malt loaf is recognised as a healthy snack by the UK government's Change4Life campaign. One high-fibre Soreen Lunchbox Loaf has 90 calories and 0.21oz (6.1g) sugar, which is around 20 calories and 50% less sugar than a typical cake bar. Malt extract, meanwhile, is considered a good source of natural energy and is high in vitamins, minerals and trace elements.

No need to feel guilty about making baked beans on toast for dinner when you lack the time or inclination to cook. Half a can of Heinz Beanz counts as one of your five-a-day and provides 0.35oz (10g) of protein (more than a large boiled egg) and 0.27oz (7.7g) of fibre, which is almost a quarter of the recommended 1.05oz (30g) per day.

Ham may be a processed meat, but it’s a lean source of protein, with less than 5% fat. Look for a nitrite-free versions, which don’t contain the chemicals linked with colon cancer. It’s worth noting that ‘no added nitrite’ does not always mean nitrite-free, as celery extracts with naturally high levels of nitrite are often added instead.

If you’re a peanut butter fan, you’ll be thrilled to know that a couple of tablespoons provide 1.5mg of vitamin E and nearly a quarter of your daily requirement of niacin, which is vital for energy release, healthy skin and a well-functioning nervous system. It also provides 0.07oz (2g) of fibre (not far off the 0.09oz/2.8g in an average slice of wholemeal bread) and a heart healthy ratio of unsaturated fats to saturated fats. For added reassurance, seek out natural peanut butter with an ingredients list that’s free from additives, preservatives, added sugar and sweeteners.

Can’t function without your morning cup of joe? Well, that’s OK, because drinking coffee can deliver a whole host of benefits. It’s believed to decrease the risk of developing both endometrial and liver cancers, as well as type 2 diabetes. It’s also thought to support brain health, boost energy levels and could contribute to liver health. Having said that, too much can make you feel jittery or even cause heart palpitations, and women who are pregnant or breastfeeding should limit their caffeine intake according to guidelines.

The negativity surrounding carbs such as pasta has become so widespread in diet culture, it’s often forgotten that healthy eating guidelines from around the world universally recommend that starchy carbohydrates, especially whole grains, should be a key part of our meals. Both white pasta and whole-grain pasta score well on the glycaemic index, too, with a GI of below 50. Choose whole-grain pasta for more fibre.

Cod fish fingers are a really good source of iodine, a mineral that can help to keep the thyroid gland, which controls metabolic rate, healthy. Four baked fish fingers supply, on average, 0.5oz (14g) protein and a minimal 0.02oz (0.7g) saturated fat (the type of fat that can raise cholesterol levels), so they're a lighter option, too (and delicious in a sandwich).

Popcorn is a whole grain and only becomes unhealthy when it has lots of fat, sugar and/or salt added (or if you munch your way through a bucket load). Choose individually sized bags to make portion control easier – or make your own, so that you can dictate the ingredients list entirely.

The more cocoa that chocolate contains, the lower it is in sugar and the higher it is in polyphenol antioxidants, which have been shown to reduce blood pressure. Very dark chocolate also has a surprising amount of fibre, which helps to boost gut health – for example, 1.8oz (50g) of Green & Black’s 85% cocoa chocolate supplies 0.2oz (6g) fibre – equivalent to one-and-a-half small bowls of bran flakes.

Sure, milk chocolate has fewer antioxidants and a higher sugar content than its dark counterpart. But it’s not all bad news: 1.8oz (50g) milk chocolate has as much bone-building calcium as a 6fl oz (175ml) glass of milk, while simultaneously delivering more fibre than a small apple.

A 0.9oz (25g) bag of crisps provides more potassium than an average banana – and 40% more vitamin C than a small bunch of red grapes. These days, most crisps are also fried in sunflower or rapeseed oil, which is high in unsaturated fat and won't raise your blood cholesterol. Do keep salt content and portion sizes in mind, though.

There’s no denying that Marmite does have a relatively high salt content, but it’s also a powerhouse of B vitamins, which aid the nervous system and help release energy from food. For the ultimate quick meal that’s also comforting and healthy, dip wholegrain toast soldiers lightly spread with Marmite into a runny boiled egg.

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Last updated by Emily Shardlow-Price.