This tiny molecule is a big player in heart health: It keeps blood vessels relaxed, which maintains healthy blood pressure, and discourages atherosclerosis by making artery walls more like Teflon so that white blood cells and clot-producing platelets can’t stick. Nitric oxide, or NO, also suppresses overgrowth of muscle cells in artery walls, which keeps blood vessels from thickening, and it helps cut production of free radicals. NO is found throughout the animal and plant kingdom. It’s the chemical trigger that makes lightning bugs flash their yellow-green lights on summer nights. Eating foods rich in arginine (NO’s building block), such as beans, fish, nuts, and soy, can boost NO production, as can cutting back on saturated fat and getting up off the couch.
Are you at risk? Your artery linings produce their own supply of NO. If the lining’s not healthy, production drops. (Another link: Low NO may be associated with higher levels of inflammation.) There’s currently no widely available lab test for NO levels, but it’s a good bet you aren’t producing as much as you could if you are overweight, inactive, or a smoker, or if you have high levels of cholesterol, homocysteine, and/or Lp(a).