Why Popeye was wrong about spinach, and 9 other health food myths debunked
Published 12/05/2015 | 11:52
Is agave syrup really better than sugar? Is sushi healthy? Nutritionist Fiona Hunter exposes the most popular myths about our diets
1. Agave syrup is better for you than sugar
Fans of agave claim that it is better for you than sugar and other sweeteners because it has a low GI, which means it causes less of a spike in blood sugar levels than other types of sweetener. While this is indeed true, one of the reasons that it has low GI is because it has a high concentration of fructose. High intakes of fructose raise levels of a type of fat, called triglycerides, in the blood, which could increase the risk of certain health problems, including heart disease.
2. Spinach is a good source of iron
The truth is that Popeye got it wrong. Although spinach contains iron, it also contains a substance called oxalic acid which binds to the iron, making it difficult for the body to absorb. Other green leafy veg, like kale, don’t contain oxalic acid, so they are a better source of iron. But even they provide only a fraction of iron that you would get from red meat, which contains much more iron and in a form which it is easy for the body to use.
3. Chia seeds contain the same type of healthy fats as oily fish
Although chia seeds do contain omega-3 fats, it’s a different type of omega-3 to that found in oily fish like salmon and mackerel. The omega-3 in fish is in the form of docosahexaenic acid (DHA) and eicosapentaenoic acid (EPA), and it is these two fatty acids that are believed to be important for the heart, brain and eyes. Chia seeds, along with other foods like linseeds, rapeseed oil and walnuts contain mainly omega-3 in the form of alpha-linolenic acid (ALA). Although the body can convert some ALA to DHA and EPA, it is not a very efficient process, with less than 10 per cent of ALA being converted.
4. Spelt flour is gluten-free
Wrong. Spelt is simply an ancient variety of wheat. Although spelt contains less gluten than regular wheat, which is why some people find it easier to tolerate, it is not suitable for people with Coeliac disease.
5. Raw foods are more nutritious than fresh
Not always. Cooking things like carrots and tomatoes will help to break down the tough cell walls, which will liberate some of the phytochemicals which otherwise would be locked into the cells and unavailable for the body to absorb.
6. Sushi is better than a sandwich for lunch
Despite its goodie-two-shoes reputation, sushi can have more calories than a sandwich. It may be low-fat, but it’s also usually high in salt and doesn’t offer much in terms of your five-a-day or protein. So it's unlikely to keep you feeling full for long.
7. Coconut milk yogurt is better for you than regular yogurt
Unless you can’t eat dairy, there’s absolutely no advantage and several potential disadvantages of choosing coconut milk yogurt over regular yogurt. One small pot of Co-yo coconut milk yogurt contains around 21g of saturated fat, which is more than you should eat in entire day. Another downside is that unlike traditional yogurt, it doesn’t usually contain any calcium.
8. Fat free salad dressings are healthier choice
In terms of calories, fat-free dressings might seem like a better choice, but studies have shown adding a small amount of an oil-based dressing to salad will help the body absorb phytochemicals like betcarotene and lycopene from the salad.
9. Fresh fruit and veg are better for you than frozen
Research from Hallam University, Sheffield revealed that frozen fruit and veg can actually contain higher levels of vitamins than fresh. This is because they are frozen within hours of being harvested and the vitamins are locked in, whereas some fresh produce can be over a month old before it reaches the supermarket shelves.
10. Manuka honey is better for you than sugar
Despite the health claims and the inflated price tag, there are no credible scientific studies to suggest that eating this honey offers any real benefits.