pegruns, as a runner, I'm not sure you want to cut down on (complex) carbs. You need them for energy! This <a href="http://www.coolrunning.com/engine/2/2_1/162.shtml" target="_blank">article</a> explains it well.<br><br>
I believe lowering cholesterol has more to do with cutting saturated fat. You're exercising; that helps. Some people have high cholesterol no matter what they do to reduce it and may need medication.<br><br>
Some dietary tips on reducing cholesterol <a href="http://nhlbisupport.com/chd1/S2Tipsheets/foodgroup.htm" target="_blank">here</a>.
I would look at the type of carbs you are eating and the types of sugars you are eating. Try to eliminate the refined products from your diet. Cutting carbs and sugar is going to have little effect on your cholesterol, as that is not where the main sources of cholesterol come from, they come more from saturated fats and mostly animal products.
How much are you running? If it's a 30-45 minute run ~3 x a week you will probably be OK on a lower carb eating plan. If you are marathon training or have some goal races, you might experience fatigue.<br><br>
There's variation in how individual body's use and process fuel. I train for marathons and usually average 50% or slightly less calories from carbs. For other distance runners, that's low.<br><br>
Eating enough unsaturated fats and soluble fiber (from complex carbs), and limiting saturated and trans fats, often prove to be a more effective and specific dietary intervention for cholesterol.