Exactly What Causes Low Blood Pressure, According to Doctors
What Causes Low Blood Pressure?
Here's a scary stat: heart disease is the leading cause of death for women in the U.S., according to the Centers for Disease Control and Prevention (CDC). Add that to the fact that about half of Americans have at least one key risk factor for heart disease, such as low blood pressure (which causes poor blood flow to the heart and other organs) and don't know it. But there's good news in all these grim numbers: "Blood pressure remains the major reversible cardiovascular risk factor," says Mark Moyad, M.D., M.P.H., author of The Supplement Handbook.
Read on to find out seven possible causes low blood pressure, and how to raise yours if needed for a ticker that's in tip-top shape.
What Is Low Blood Pressure, Exactly?
Hypotension, the medical term for low blood pressure, is classified as a reading of 90 mmHg systolic (the top number in blood pressure reading) over 60 mmHg diastolic. Symptoms of low blood pressure (including weakness, dizziness, fatigue, and sweating, among others) can occur in one person with a low reading and not another, says Dr. Moyad. In fact, unless there is an underlying disease, having low blood pressure is often an indicator of good health.
So what causes low blood pressure? There are often a few factors that may be causing yours to drop. Keep reading to discover ‘em all. (Related: The Most Common Causes of High Blood Pressure, Explained)
Dehydration is one of the most common causes of hypotension, resulting in dizziness and weakness, says Dr. Moyad. If you suffer from frequent dehydration, be mindful of how you're hydrating. Consume less alcohol and more water."Remember this saying: 'Clear is Cool,'" he says. "This means your urine should be clear in color (a sign of hydration) and not dark yellow." Other hydration helpers include foods with more sodium and reducing the intake of potassium-boosting foods.
Another common cause of dehydration? Over-exercising, according to Jay Wohlgemuth, M.D., senior vice president and chief healthcare officer at HealthTap. "If you really overdo it (especially in the heat) and need to replenish, sometimes water isn't enough," he says. "Make sure to hydrate with an electrolyte replacement like Gatorade to hydrate quickly." Dr. Wohlgemuth notes that frequent travelers should be mindful too, as airplane travel can leave you feeling dehydrated. (Check out exactly how to stay hydrated while training for an endurance race.)
Eating Large Meals
Postprandial hypotension, which is when your blood pressure drops suddenly after a meal, is common as we age, says Dr. Moyad. "Try not to eat large meals. Smaller meals with fewer carbs tend to prevent blood pressure swings." (Related: Finally, An Easy-to-Follow Guide to Portion Sizes)
Preexisting Heart Conditions
A slow heart rate, valve disease, or other heart problems that can prevent the heart from adequately pumping blood could also be causes of low blood pressure. If you have symptoms such as vision changes, fainting, or frequent dizziness, you should talk to your doctor about the possibility of having a larger heart condition. (See also: This Woman Thought She Had Anxiety, But It Was Actually a Rare Heart Defect)
But both M.D.s emphasize the importance of staying calm (and not scaring yourself for no reason!). Just because you have low blood pressure doesn't mean you're also going to have a heart condition. "Work with a doctor you trust to determine if you have low blood pressure with symptoms," says Dr. Moyad. "Having just low blood pressure might mean the healthiest option for you to do is nothing. Your doctor will do a series of blood tests among other evaluations to determine if there is a reason for this drop." If there's not, your pressure may change simply because of age or lifestyle changes, such as cutting back on drinking and smoking.
Sometimes a change in blood pressure can be blamed simply for sticking another candle in your birthday cake. "As we get older, our ability to handle drops or changes in blood pressure changes, and we become more sensitive to these changes," says Dr. Moyad. (Here's how to calculate your heart's age to determine if your ticker is aging faster than the rest of your body.)
"Many supplements can cause blood pressure drops," says Dr. Moyad. These include arginine, citrulline, fish oil, melatonin, anti-stress supplements, and even some calcium supplements. Some prescription drugs can do the same, he adds. So make sure you talk to your doctor about the possible side effects before starting a new medication. (Psst... have you heard about vitamin IV drips? Here’s what you need to know about this trendy treatment.)
Anemia, a condition in which you have a reduced number of red blood cells to carry oxygen throughout your body, can increase your risk of hypotension. Symptoms of anemia are similar to those of low blood pressure, such as lack of energy, dizziness, and feeling weak. (Oh and add increased risk for bruising to the anemia symptom list.)
Causes of anemia range from illness to your diet, so make sure you talk to your doctor about your symptoms and the best form of treatment if you suspect you might be suffering from anemia.
Hormone conditions from low blood sugar to thyroid disease may also cause low blood pressure, says Dr. Moyad. Be diligent about your yearly physical. Your doctor will take blood work that could flag these problems early on, so they can be treated and prevented earlier.
Chronic conditions such as an adrenal insufficiency or nervous system disorder could cause orthostatic hypotension, which is a form of low blood pressure that happens when you stand up, according to Dr. Wohlgemuth. While mild symptoms are generally nothing to worry about, if you have symptoms for a few hours or days you should seek medical treatment to find out what's really going on, he explains.
A Note About Your Blood Pressure Levels
While you might be alarmed to find you have low blood pressure and are investigating what causes low blood pressure in your body, Dr. Moyad stresses the importance of making sure you get an accurate reading. Many factors can influence your blood pressure levels, from stress right before the measurement to keeping your legs crossed—even having a full bladder. This is why it's important to know your average blood pressure, in the event that at your yearly physical you get a number that skews way too low (or high).
If you're really concerned, Dr. Moyad recommends taking your blood pressure at home every few months to keep a current record. You can get an at-home monitor online or at drugstores for under $100. "No other health number in medicine has such a large variation or risk of being inaccurate," says Dr. Moyad. "It's important to know your numbers to know the difference between a problem and being inaccurate." (Up Next: What You Should Know About Your Resting Heart Rate)