The top superfoods

Walnuts

One ounce of walnuts has 2.6 grams of alpha-linolenic acid, a type of omega-3 fatty acid. Other nuts contain only 0.5 grams per ounce, and fortified juices have only 0.1 grams per cup. Walnuts are also packed with antioxidants and amino acids, and they're rich in fibre and protein.

Lemons

Pucker up: Drinking lemon water first thing in the morning cleanses your liver, giving your body a mini detox by "gently keeping your bowel processes regular," says the Toronto-based naturopathic doctor Cara MacMullin. Squeeze half a lemon into lukewarm water and drink 20 minutes before breakfast. This citrus fruit also boasts vitamin C and potassium.

Green Tea

Consumed for ages in Asia, this brew contains polyphenols, which have strong antioxidant properties. Studies show that drinking green tea may lower your risk of developing certain cancers, and researchers are investigating its role in preventing liver disease, diabetes and high cholesterol. If that's not enough to sway you to sip, green tea may also help with weight loss. All that is enough to convince us that green tea deserves some of our coffee time.

Button mushrooms

These mushrooms may seem like innocuous salad filler, but they're actually gaining notoriety for their healthful properties. This unlikely superfood is a source of B vitamins, which help break down carbs into energy-boosting glucose and aid the normal functioning of the nervous system. They may also offer an immune boost: A recent study at Tufts University in Boston found that common mushrooms may ward off viruses and help fight cancer tumours in mice by increasing the immune system's killer-cell activity. But the best part is that they're high in umami, a savoury flavour that's also abundant in fattening food. When you're craving French fries, cook up some mushrooms instead and see if that doesn't satisfy you.

Tomatoes

It doesn't get any juicier - or healthier - than a summerfresh tomato. The red ones are packed with the most lycopene, a fat-soluble antioxidant that may lower your risk of heart disease and cancers of the cervix, breast, bladder, skin and lungs. Add them to omelettes and salads, or chop them up to make a fiery salsa for weekend entertaining.

Kale

This curlier cousin of cabbage and broccoli is impressively high in beta carotene and vitamins A and C, not to mention sulforaphane, a compound that researchers suggest can prevent cancer by helping the body eliminate carcinogens. (Mom was right: We shouldn't leave the table before eating our greens.) Try it roasted or steamed with salt and garlic.

Dark Chocolate

Long the cure for a broken heart, dark chocolate may actually help prevent heart disease. New research has found that eating even a small amount every day reduces inflammation associated with cardiovascular disease.

Researchers credit dark chocolate's antioxidant flavonoids. "The higher the cocoa content, the better, says the Toronto-based dietitian Susan Fyshe.

Berries

Raspberries, blueberries and strawberries: Take your pick. They're all full of disease-fighting phytochemicals, which can help prevent certain types of cancer. Buy extras - organic is best, because non-organic berries are heavily sprayed with pesticides - and freeze them: Berries frozen at peak ripeness have higher nutritional value than the ones shipped north in the winter.