Time-honoured guilty pleasure foods may not always be the nutritional bad boys we perceive them to be.
In recent years, scientific research has cast light on the hidden health benefits of all kinds of "bad-for-you" cuisine, throwing into doubt their position on the culinary naughty step.
For example, one study found that full-fat dressing may actually be better for you that its low-fat equivalent, while eating butter could help to burn fat. Meanwhile, chocolate and popcorn bring together a chorus of nutritional value (when eaten in the right way).
That's not to say that these foods don't come with their own (well-documented) health risks. They're just better than we originally thought them to be and may actually boost wellbeing, when consumed in moderation and as part of a healthy diet.
We take a closer look at the science behind the health-giving perks of guilty pleasure food and drink, along with guidelines on recommended daily intake for each.
Photos: Rex Features
Full-fat salad dressing
A ground-breaking 2011 study published in Molecular Nutrition & Food Research came to the startling conclusion that full-fat salad dressing may actually be better for you than its low-fat equivalent.
Researchers at Purdue University served up veggie salads topped with full-fat dressings, compared to low or no-fat versions and then ran blood tests on participants. They found those who ate salads with the greatest amount of fatty dressings absorbed far higher rates of antioxidants than those who did not, including four times the level of lycopene, seven times the lutein and 18 times the beta carotene.
Why? Many of the nutrients in leafy green vegetables are fat-soluble, meaning they need to be eaten with some fat so that the body can adequately absorb the nutrients.
"Certain foods become healthier when eaten together," says nutritionist Vicki Edgson. "Many vegetables are fat-soluble, which means your body absorbs their nutrients better when you eat a little fat with them.The more nutrients your body absorbs, the less hungry it feels, plus you’ll get fewer sugar cravings."
How much should I have? As always, moderation is key and you should still be wary of shop-brought dressings with high fat or calorie content. The best thing to do is make your own dressing at home using healthy fat sources such as olive oil and avocado. The average woman should eat no more than 20g of saturated fat a day (30g for men).
Bursting with antioxidants, vitamins and minerals including potassium, copper, magnesium and iron, dark chocolate is an enriching food source.
Dark chocolate has been linked to a short-term increase in brain function, lower blood pressure and increased cardiovascular health, thanks to the presence of flavanols, which improve blood flow to the brain and heart, and make blood platelets less likely to clot. Eating it raises levels of pleasure-giving endorphins and may increase your serotonin levels for an improved mood.
How much should I have? Despite its benefits, chocolate is still loaded with calories and easy to overeat. Stick to approximately 30g to 60g a day (roughly 1 to 2 ounces) of high quality, dark chocolate with a cocoa content of 70% or higher.
Yes it's hard to believe, but cheese in general can be good for you. It's a great alternative source of protein and high-quality natural fat, and is brimming with calcium, vitamin D and good bacteria.
"Cheese is one of the best foods you can eat for your teeth," says Matthew Messina, DDS, an American Dental Association spokesman. "It's a good source of calcium, to keep your teeth strong. Plus, eating cheese can lower the levels of bacteria in your mouth and keep your teeth clean and cavity-free."
Mozzarella is a good choice as it has a lower calorie content than many cheeses (one ounce contains 72 calories and 4.5 grams of fat), and contains niacin, riboflavin, thiamine, biotin and vitamin B6 for healthy skin, vision and the formation of red blood cells.
How much should I have? Cheese can be high in fat and salt, so it's important not to go overboard. Most people need 2-3 servings of dairy a day, which equates to around 120g ricotta cheese. The NHS recommends keeping an eye on how much cheese you eat, and how often.
The heart-healthy benefits of red, red wine are well documented. Red wines contain high levels of polyphenol antioxidants, and, in general, the darker the wine, the higher the antioxidant content - in tests, cabernet sauvignon grapes were shown to contain the most polyphenols.
Resveratrol is the key component here. Found in the skins of grapes used to ferment wine, it has been linked to a reduced risk of inflammation and blood clotting and has important anti-ageing properties (red wine is fermented for longer than white wine, so contains more resveratrol).
But the health risks associated with drinking alcohol are significant, and scientists warn against drinking red wine solely for its potential health benefits.
How much should I have? It's best to drink wine in moderation with food and stick to recommended daily guidelines of 2-3 units (a 175ml glass of wine) for women or 3-4 units for men.
For decades, nutritionists have thought of butter as the baddie of the food world. But last year, scientists who drew together data from 72 studies found no evidence to support the notion that butter's saturated fat increases the risk of heart disease.
In fact, the natural fat of butter may actually be better for you than the processed trans fats found in hybrid spreads or margarine. Butter contains antioxidants vitamin A, vitamin E and selenium, as well short and medium chain fats, which increase fat burning. It has even been linked to weight loss, possibly because of the impact of feeling fuller, faster.
How much should I have? "Butter usually has seven grams of saturated fat per tablespoon, so keeping intake to less than three teaspoons (or one tablespoon) per day is ideal," says Lesley Young, of Canada's Best Health mag.
A 2012 study from University of Scranton researchers found this time-honoured cinema snack to contain more polyphenols - healthful antioxidants - than fruit and vegetables (popcorn contained 300 mg of polyphenols a serving, compared to 114 mg for a serving of sweet corn and 160 mg for all fruits per serving).
Scientists pointed out that polyphenols are more concentrated in popcorn, which averages only about 4 percent water, while polyphenols are diluted in the 90 percent water that makes up many fruits and vegetables. Hulls of the popcorn were found to be "nutritional gold nuggets" with a high concentration of polyphenols and fibre.
"Popcorn may be the perfect snack food, said lead researcher Joe Vinson. "It's the only snack that is 100 percent unprocessed whole grain. One serving of popcorn will provide more than 70 percent of the daily intake of whole grain. The average person only gets about half a serving of whole grains a day, and popcorn could fill that gap in a very pleasant way."
How much should I have? Obviously, how healthy popcorn is depends on how you cook it and what you serve it with; air-cooked popcorn has around half the amount of calories as microwaved versions - and neither can replace fruit and veg. For a balanced diet, aim for three to five servings of whole grains a day.
For every study that shows that drinking coffee causes increased blood pressure, anxiety,indigestion and insomnia, there’s another that indicates it reduces depression, improves memory, reduces liver cancer risk and even help to ward off Alzheimer’s Disease.
It can also work as something of a beauty elixir, to exfoliate dry skin and reduce the appearance of puffy eyes.
How much should I have? The general advice is that four or five cups of coffee a day is safe, around 400mg of caffeine.
“If you enjoy a cappuccino in the morning then that’s fine, but if you start to get palpitations, you’re running to the toilet or noticing an increase in nervousness and sleeplessness, you should probably cut back your caffeine intake,” says dietician Gaynor Bussell, registered dietician with the British Dietetic Association (via the BBC).
We don't instinctively thing of guacamole as a healthy option, because we associate it with food such as tacos and burritos. But despite the relatively high calorie content of avocados (322 per fruit), guacamole is a hotbed of nutritional value.
For one, the avocados in guacamole contain fibre and unsaturated fats, to help digestion and potential heart problems. They contain high levels of potassium to lower blood pressure and get rid of excess sodium in the body. They're also a good source of vitamin K (one avocado contains nearly 50% of recommended daily intake for women) to help absorb calcium, vitamins A, E and C, all of which boost your immune system to ward off illness and infections.
How much should I have? Experts seem to agree that one avocado a day is a great way to incorporate these health-giving veg into a balanced diet.