Olive oil, potatoes, and 5 other foods you've probably been eating wrong.

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From chia seeds, to coffee, to the humble potato — you could be losing the valuable nutrients in your food while you eat it. This sounds weird, but the amount of goodness you get from your meal or snack is largely determined by how you prepare it, and what you add to it.

Here are some tips to help you can get the maximum amount of nutrients from seven popular foods you are probably eating wrong.

1. Coffee

Melanie McGrice, a dietician based in central Melbourne, says that while coffee has been shown to reduce the risk of diabetes, “in order to reap the benefits, you should have it black without sugar.” So a caramel-mocha-frappuccino probably doesn’t count. Black, no sugar. Got it. (Post continues after gallery.)

2. Orange juice

It’s no secret that many store-bought varieties of OJ are high in sugar, and should only be consumed occasionally. However, there’s another reason why fresh is better: the vitamin C content “degrades quickly in light” says Melanie. In other words, those fluorescent supermarket lights could be sapping your orange juice of the vitamin it’s best known for.

“If you’re going to drink juice, instead of buying store bought juice, always squeeze it fresh,” Melanie says. There you have it.

3. Olive oil

We all know olive oil is good for us - but what you may not know is that it all depends on how you use it. In order to get the health benefits from olive oil, which include lowering the risk of heart disease, high blood pressure and stroke, Melanie explains that it is best used uncooked.

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"Olive oil has a low smoking point so degrades quickly when heated. Use it on salads instead of in cooking," Melanie says.

4. Chia seeds

While many people love sprinkling whole chia seeds onto their breakfast, the health benefits of the little seeds are increased if the seeds are milled first. One study, published in the Journal of Alternative and Complementary Medicine, found that the benefits of ALA — the plant form of omega-3 fatty acids — increased by 58 per cent when the seeds were milled, as compared to the whole seeds. So to reap the benefits of chia, grind the seeds before using them. Buy them pre-ground or throw them in a coffee grinder or spice mill so you don't end up flushing the health benefits away.

5. Potatoes

I'll be honest — this is probably the most mind blowing food fact I've learned so far. I have always peeled potatoes because it gets the dirt off easily and I usually can't be bothered scrubbing them, but no longer! As Melanie told me, "most of the nutrition in potatoes is found in the skin, so if you're going to eat potatoes, always leave the skin on." (Post continues after gallery.)

6. Yoghurt

That watery substance sitting on the top of your Greek yoghurt? Don't tip it down the sink. That's whey, and it contains protein and vitamin B12, calcium and phosphorus. Whey is also a rich source of cysteine, the rate-limiting amino acid for synthesis of the potent antioxidant glutathione. According to the European Journal of Nutrition, whey is important for a healthy immune system, as it contains immunoglobulins and is rich in the amino acid glutamine. So mix the watery substance in to the rest of your yoghurt to ensure you get all the nutritional benefits from yoru yoghurt.

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7. Tea

Everyone has a particular way they like their tea — but after reading this I am about to change mine and stop reaching for the milk. Adding milk to tea can strip it of its beneficial effects. Black tea has been proven to significantly improve vascular function, but if you add milk, it completely blunts this effect. It doesn't, however, affect the antioxidants in tea.

Did you know about any of these tricks?

On that note, check out ten foods you should be stoking up on in your weekly shop...