This may be good for your heart, but too much of it can make you put on weight, says Jaclyn Reutens, a dietitian at Aptima Nutrition & Sports Consultants. One tablespoon provides 135 calories and 15g fat. It is easy to overdo olive oil without realising it, she cautions. “In cooking, most people tend to be liberal with its usage because they think it’s good for them. But if you drown your salads with olive oil, you can easily be consuming three tablespoons of olive oil, which is a whopping 405 calories!” Her advice: use the olio sparingly, drizzle it in salads and if you are using a non-stick pan to cook, one tablespoon is more than enough.