Think you know how to minimize your risk of deadly heart disease? Think again. The usual suspects (smoking, hypertension, cholesterol) do not tell the whole story.

Here are three surprising risks that you -- and your doctor -- might not know about, says Stephen T. Sinatra, a board-certified cardiologist and the co-author of "Reverse Heart Disease Now" (Wiley, $24.95).

SUGAR.  "Most people think of high cholesterol as the main culprit," Sinatra says, "but sugar blows cholesterol out of the water." He says sugar inflames the blood vessels, leading to increased clotting, pre-diabetic insulin resistance, diabetes, metabolic syndrome and obesity. What you can do: Avoid high-glycemic foods; maintain a trim waist size (he suggests less than 38 inches for men and 32 inches for women); and eat a high-fiber diet.

FATS. Fats have a bad rap, but "eliminating them is like throwing the baby out with the bath water," Sinatra says. He explains that fats belong to one of three groups: the good (mono and polyunsaturated), the bad (saturated) and "the enemy" (trans fats). What you can do: Read labels; include good fats (wild Alaskan salmon, walnuts) as 30% of your calories; and eliminate trans fats.

TOXIC BLOOD. Blood-thickening elements that age you inside and out are a "very significant cardiovascular risk factor, especially for women," Sinatra says, "even if cholesterol is normal." What you can do: Ask your doctor to check your blood for elevated homocysteine, lipoprotein (a), C-reactive protein, fibrinogen and ferritin.