One tablespoon of granulated sugar is about 12.5 grams. One gram of sugar is about 4 calories, so that's about 50 calories per tablespoon. To use an everyday example, there's 50 calories in 2.5 of those little brown packets of Sugar in the Raw you see at Starbucks.
In one week, cutting back on just one tablespoon of sugar per day adds up to 87.5 grams of sugar and 350 calories.
If you weighed around 155lbs, it would take about 30 minutes to burn 350 calories running at a 10 minute/mile pace (6.0 on your typical treadmill.) Cutting back on the sugar seems real easy now!