Not all foods are created equal. Some superfoods contain more nutrients than others or have medicinal effects that reach beyond nutrition. For example, an apple is not equivalent to an orange. An orange has 10 times more vitamin C and beta-carotene, four times more thiamine and a whopping 40 times more folate, a B vitamin that helps prevents birth defects. Likewise, broccoli is nutritionally superior to beans or zucchini (as are its relatives, cauliflower, cabbage, kale and brussels sprouts). Liver towers over red meats. Garlic lords it over leeks, onions, shallots and chives, even though they are all cousins. Dark chocolate is the one with the catechin antioxidants (the more bitter, the better), while milk chocolate has only around one third. White chocolate? Forget it.
New research morphs everyday foods into “healing foods”. Cinnamon (three grams a day – about half a teaspoon) has been shown to lower blood glucose in people with diabetes. Rosemary and oregano are documented to have high antioxidant levels, along with antibacterial qualities, which are thought to explain why these herbs helped preserve meat dishes in times before refrigeration. And tea doesn’t have to be green to be good. A cuppa of regular tea now appears to contain the same antioxidant potential – both come from the same bush Camellia sinensis.
But how do you make each kilojoule count?
Dr Adam Drewnowski, director of the Centre for Public Health Nutrition at the University of Washington, has ranked the nutritional value of hundreds of natural foods against the kilojoules they provide to come up with what he has dubbed “naturally nutrient-rich foods”. “These maximise the vitamins, minerals and protein for every kilojoule you consume.” Among vegetables – generally, a nutritionist’s delight – Drewnowski has calculated that the superstars are spinach, dark-green lettuces (mignonette, rocket, baby spinach leaves) and orange sweet potato (kumara). “You get the highest quantities of vitamin C, folate, fibre, and minerals without overloading your system.”
In the grains group, Drewnowski has identified brown rice, barley, wholegrain bread and wholegrain cereals as having the most nutrients for every kilojoule. Low-fat milk and low-fat yoghurt give you the most bang for your dairy buck. And in the protein group, top of the class are beef steak, pork loin, eggs, salmon, black beans and almonds.
Top fruits? Avocado, oranges, grapefruit, kiwifruit, blueberries and strawberries. It’s all about informed choices. It’s all about informed choices