Man holding matcha latte at cafe

Superfood myths

There’s a new “superfood” claim almost every week. We sort the facts from the fiction.

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Dark chocolate

Dark chocolate is touted as a guilt-free treat, claimed to lower blood pressure, improve insulin resistance, and reduce inflammation and plaque build-up in blood vessels. Unfortunately, if you’ve been convinced you can chow down on dark chocolate for the health benefits you might want to stop reading!

Dark chocolate’s main selling point is its cocoa content. Cocoa has high levels of flavonoids – substances found in plants that have an antioxidant effect. Gram for gram, cocoa contains more flavonoids than foods such as tea, apples and berries, which are also high in the stuff.

But there are healthier ways to boost your flavonoid intake. While dark chocolate is a better option than white or milk chocolate, it’s definitely not a health food. Cadbury Old Gold 70% Cocoa and Whittaker 72% Dark Ghana are both more than 20% saturated fat and about a third sugar.

Our verdict: Eating a small amount of dark chocolate won’t do you any harm but don’t kid yourself about your chocolate fix giving you a health boost.

Butter

You can’t beat the taste of butter on a baked potato or hot toast, and some claim butter’s better than marg because it’s natural and less processed.

But for butter lovers, the news isn’t great. Butter has about 50% saturated fat and high levels of sodium. Healthy eating guidelines recommend replacing it with vegetable oil-based spreads, avocado, hummus or nut butters, which are all high in monounsaturated or polyunsaturated fats.

Table spreads weren’t always a healthier alternative to butter. Early products contained “bad” trans fats that packed a double whammy for heart disease by raising levels of LDL (bad cholesterol) and lowering levels of beneficial HDL cholesterol. These days, manufacturers have changed their processes and most spreads have negligible levels of trans fats.

Although we refer to marg, there are no true margarines on shelves anymore. The Food Standards Code says margarine must contain at least 80% fat but consumer demand for lower-fat spreads (table spreads) means companies don’t bother making marg.

Our verdict: Despite the hype, the evidence isn’t backing butter.

Activated almonds

Celebrity chef Pete Evans snacks on them, Nutty Bruce and Pureharvest almond milks are made with them, and you can buy a bag at your local health food store. Activated almonds sound hi-tech but they’re simply almonds that have been soaked in water for 12 hours to improve the digestibility and nutrition of the nut. That’s the theory anyway.

However, as far as the science goes, there’s no evidence activated almonds (or any activated nuts) are better for you. A 2017 University of Otago study, published in the European Journal of Nutrition, concluded that soaking nuts didn’t make them easier to digest or more nutritious.

Our verdict: Almonds are a good source of heart-healthy fats and nutrients. The best way to get a nutty boost is consuming them raw and unsalted – activating them won’t result in any extra benefits. But they are a high-kilojoule snack so limit yourself to a small handful.

Turmeric

Been swapping your flat white for a turmeric latte in the hope it’ll alleviate your arthritis? The herb is getting plenty of airtime as a result of supplement ads featuring Richie and Gemma McCaw.

It’s the curcumin – which makes up about 3% to 5% of turmeric – that supposedly gives the herb its “superfood” status. It’s been used for centuries in traditional medicine but a 2017 report in the Journal of Medicinal Chemistry concluded the compound had limited, if any, therapeutic benefit.

It also concluded curcumin is unstable on its own, and not readily absorbed by the body, so it’s tricky to test efficacy.

A previous review published in the Journal of Medicinal Food in 2016 concluded more rigorous and larger studies are needed to confirm the efficacy of turmeric for arthritis. It also found trials supporting turmeric for the treatment of arthritis used a turmeric extract with about 1000mg of curcumin a day – that’s a lot more than you’d add to your curry or latte.

When it comes to turmeric supplements, it’s hard to compare what’s on the shelf. Levels of active ingredients and recommended doses vary. Turmeric may also be combined with other compounds such as piperine – a substance found in black pepper – to increase bioavailability.

Our verdict: Adding turmeric to your curry or latte adds flavour and colour, but the research doesn’t back its superfood status just yet.

Coconut oil

There are lots of claims for coconut oil – “beneficial in weight loss programmes” and “helps heart health” among them.

Advocates say it contains a high percentage of lauric acid compared with other saturated fats. They claim lauric acid is a medium-chain triglyceride (MCT). MCTs are less likely to be stored in fat tissue than long-chain triglycerides (LCTs), found in most oils. This is what gives rise to the weight-loss claim. However, lauric acid acts like an LCT in the body so the MCT evidence can’t be applied to coconut oil.

It’s claimed populations in the Pacific whose diets were traditionally high in coconut had excellent cardiovascular health. But these cultures used to eat coconut milk and cream, rather than the oil, and their diet was based on fresh fruit, vegetables and seafood. They also weren’t filling up on foods such as cheese, butter and takeaways, which are common sources of saturated fat in diets today.

For cooking, there’s evidence coconut oil is a healthier option than butter, but there are better options. Coconut oil is high in saturated fat – 91%. That makes it far more saturated than most other oils and fats (olive oil is about 15% and canola oil 7%). Healthy eating guidelines recommend we eat less saturated fat.

Our verdict: Using small amounts of coconut oil to add flavour is fine, but it’s not a healthy choice. Stick to healthier fats from other plant oils, oily fish, nuts and seeds.

Green tea and matcha powder

Green tea (as well as black and white) contains flavonoids and antioxidants that are beneficial for health. Matcha is a powder made from green tea and is said to have much higher levels of the good stuff. The longer you leave your tea to brew, the higher the levels.

Among the clutter of claims made is that green tea can help prevent cancer.

A 2009 Cochrane Review looked at 51 studies on the association between green tea and different types of cancer. The authors concluded the studies, which involved more than 1.6 million people, provided insufficient and conflicting evidence regarding green tea and cancer prevention. A 2013 study published in the American Journal of Clinical Nutrition came to a similar conclusion, finding studies didn’t confirm or refute the role of green tea in preventing cancer.

What about weight loss? Can green tea help you sip yourself slim? It’s been claimed green tea can increase your energy output due to its levels of caffeine and catechins – a beneficial substance found in tea. A 2012 Cochrane Review of 14 randomised control trials found that weight loss in participants taking green tea wasn’t significant in most studies, so wouldn’t have any clinical importance. All trials used a green tea preparation – rather than brewing green tea from a teabag – so active ingredients would be higher than you’d typically get at home.

Our verdict: Green tea is a source of antioxidants and is kilojoule-free, so it’s a good substitute for high-kilojoule drinks, such as soft drinks and hot chocolates. However, it’s not a panacea for your ills.

Cheaper alternatives

While there’s no shortage of pricey “superfoods” touting their nutritional benefits, you can often find alternatives for a fraction of the price.

GUIDE Measurements and price are per 100g. Pricing data collected in July 2018.


Blueberries vs kiwifruit

  Blueberries (frozen)[width=medium] Green kiwifruit
Vitamin C 6mg 85mg
Potassium 68mg 300mg
Price $1.20 20¢

Coconut oil vs canola oil

  Coconut oil[width=medium] Canola oil
Saturated fat 90.9g 7.2g
Price $2.80 25¢

Chia seeds vs sesame seeds

  Chia seeds[width=medium] Sesame seeds
Calcium 631mg 980mg
Iron 7.72mg 15mg
Price $2.49 83¢

Quinoa vs lentils

  Quinoa[width=medium] Lentils
Fibre 2.8g 3.7g
Protein 4.4g 7.6g
Price $2.29 89¢

Pomegranate vs oranges

  Pomegranate[width=medium] Oranges
Vitamin C 10.2mg 48.4mg
Price $4.00 30¢

When to cook?

Some fruit and veges give more goodness when they’re heated. If you cook asparagus, cabbage, carrots, mushrooms or peppers, you’ll boost the amount of vitamins in them.

Your body can pull more lycopene out of tomatoes when they’re cooked, but they’ll contain less vitamin C.

A study in the Journal of Agriculture and Food Chemistry found boiling and steaming your veges boosted antioxidant levels more than frying.


By Belinda Castles
Research and Testing Writer

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