Nobody likes a backseat driver, but listen up, because we’re taking a trip down your body’s vascular highway. It’s typically a smooth ride, with your blood flow more or less on cruise control. Oh, sure, there can be traffic jams, but that’s why you have things like your blood pressure and cholesterol checked; a worrisome reading gives you lots of time to clear the congestion (or find a surgeon who can). The scary scenario is when some drivers with optimum blood pressure and LDL numbers suddenly, inexplicably, come to a dead stop.
Scientists have a name for this hidden road hazard: endothelial dysfunction, a condition in which the lining of your blood vessels – the endothelium – doesn’t dilate properly, preventing blood from flowing freely. “The endothelium is like a sheath of Teflon lining your blood vessels to prevent clotting,” says Dr Eric Thorin, a researcher who studies the endothelium at the Montreal Heart Institute. “But it’s also the place where all blood vessel disease starts.” Left untreated, the condition’s consequences can be catastrophic.
This might seem like a good time to panic, but don’t. Follow our plan, and while you may hit the occasional speed bump, you’ll always have clear highway ahead.
Flag it
A lot of diseases are branded as silent killers, but endothelial dysfunction is like a ninja in its stealth. It often lurks in the absence of other cardiac red flags, such as high cholesterol or triglycerides, says Dr Vincent Bufalino, director of cardiology at Advocate Medical Group in Chicago. Still, there are a few indicators that can reveal this assassin hiding in the shadows.
ERECTILE DYSFUNCTION
One “ED” can lead to the other. Endothelial dysfunction – a precursor to heart disease – usually affects blood flow below the belt first, says Dr Robert Kloner, a professor of cardiovascular medicine at the University of Southern California. “If arteries that supply your penis cannot dilate properly, then you can’t get an erection. This can happen in the very early stages of atherosclerosis, even before plaque builds up in your arteries.” Also at play: the arteries supplying blood to your penis are much narrower than those feeding your heart; that means even slight shrinkage can have a serious impact, Kloner says.
DIABETES
The millions of cells that make up your endothelium have little fingerlike feelers that protrude into your bloodstream to gauge how everything’s flowing. Problems crop up when excess glucose in the blood accumulates on the feelers, diminishing their sensitivity. Worst case: If they don’t function properly, your organs could be deprived of critical oxygen.
SLEEP APNOEA
This disorder can take your breath away and leave you with endothelial dysfunction. A new Norwegian study reports that people with sleep apnea are at increased risk of endothelial dysfunction regardless of whether or not they’re overweight. Two possible reasons: persistent inflammation and an overload of blood-vessel-constricting adrenaline, which is released when people with sleep apnoea wake up during the night.
Diagnose it
The test for endothelial dysfunction isn’t as simple as having your cholesterol checked, but it’s no colonoscopy either. It requires a device called the EndoPAT. First, sensors attached to your fingertips monitor your normal blood flow; then the main artery of your upper arm is restricted with a blood pressure cuff for five minutes. When the cuff is removed, the sensors measure the change in the amount of blood pumped with each heartbeat, an indicator of your vessels’ ability to dilate. Because a computer controls the test, the technician’s level of expertise doesn’t affect the outcome, making the measurement exceptionally reliable, say Penn State researchers.
Fight it
Whether you’ve been diagnosed with endothelial dysfunction or your vessels are dilating just fine (you think), add these ED-fighting tactics to your “must do” list. Your body certainly won’t complain.
SAY NEIN TO NINE
The fatter your belly, the skinnier your blood vessels. According to Mayo Clinic research, a weight gain of just four kilos can trigger endothelial dysfunction. The good news is that dropping the same amount of weight can reverse the condition. Motivate yourself to move by organising a weight loss war among friends and family. In a new Brown University study, people who created teams and competed to drop weight, work out, and walk more often shed an average of 4.5% of their body weight. The competition helps, but so does the camaraderie. The people who slimmed down the most were often on the same teams. Choose partners who have similar goals and motivation levels so you’re all working toward a common goal. And if you can, volunteer to serve as team captain – the researchers also found that group leaders lost more flab than other members did.
BE LESS MERCURIAL
There’s been only one time when it made sense to put mercury in your mouth – and you probably haven’t seen that kind of thermometer in years. Well, you can skip the tuna too. According to a recent Brazilian study, regular exposure to even low levels of mercury – by eating contaminated fish, for example – can trigger endothelial dysfunction, possibly due to increased inflammation. To dose up on heart-healthy omega-3s minus the mercury, focus on tilapia, sardines, catfish, salmon, and anchovies, the FDA says. Not a fan of fish? Take an omega-3 supplement – just make sure it’s mercury free.
GO ON A FAT FAST
You see an order of wings, but your endothelium sees an enemy. “Saturated fatty acids are perceived as abnormal, so the immune cells try to clean them up,” says Dr Mansoor Amiji, chairman of the department of pharmaceutical sciences at Northeastern University in Boston and a researcher of treatments for endothelial dysfunction. “Instead, the cells cause more inflammation and wind up doing damage.” Before you grab any packaged food off the supermarket shelf, check the label and then do a little maths. Multiply the number of saturated fat grams by 9 to determine the number of calories the fat contributes. Multiply that number by 4.18 to make it kilojoules. Now divide that by total kilojoules. If saturated fat accounts for more than 10% of the food’s kilojoules, put the package back on the shelf.
Saturated fat isn’t the only saboteur, trans fats are the real enemy. Here’s an incentive to cut them out completely: these synthetic fats may interfere with your endothelium’s ability to regulate levels of blood-vessel-dilating nitric oxide, say University of Washington researchers.
And don’t trust food manufacturers to do the work for you: a recent Harvard analysis found that supermarket foods that were reformulated to remove trans fats reduced the stuff by only 84%. This means the old rule still applies: avoid any foods that contain hydrogenated or partially hydrogenated oils.
FILL THIS PREHISTORIC PRESCRIPTION
Stone Age men may have stressed out over saber-toothed tigers, but endothelial dysfunction? Nah. Whether they were the hunters or the hunted, these guys engaged in intense bursts of activity that look a lot like today’s running intervals, says Thorin of the Montreal Heart Institute. That’s important, because interval training improves blood flow more significantly than steady-state cardio does, according to a recent finding in the Journal of Strength and Conditioning Research. Try the study workout: warm up by walking for 10 minutes, and then run four high-intensity, four-minute intervals on a treadmill, separated by three minutes of active recovery (such as walking). Finish with a five-minute recovery.
GO WHERE NO SMOKE HAS GONE BEFORE
Cigarette smoke can choke your blood vessels even if no one is puffing in your vicinity. When researchers from the University of California at San Francisco examined the effects of simply being in a room with stale secondhand smoke for 30 minutes, they found that the residual smoke induced endothelial dysfunction. The best protection: avoid bars, restaurants, and homes that allow smoking. Failing that, hold your breath.
CAN THE ENERGY DRINKS
Energy drinks may open your eyes, but could it be closing your arteries? Scientists in Australia recently discovered that drinking a single sugar-free energy drink can cause blood to become sticky and blood vessels to narrow. They speculate that additives other than caffeine, like glucuronolactone, may be to blame. If you need an imbibable boost, make your own iced “coffee” with raw cocoa: blend some raw cocoa with low-fat milk and a few ice cubes. You’ll still take in a shot of caffeine (about 15 milligrams), plus a new Brazilian study found that a daily dose of 70% cacao dark chocolate significantly improved people’s endothelial function after just four weeks.