You know that eating a healthy diet helps lower blood pressure, but blood pressure that is too low could be a cause for concern as well. Labeling blood pressure readings as “too low” depends more on your current and past health history than on the numbers on your blood pressure unit.
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Your personal normal
Normal blood pressure is 120 mmHg systolic and 80 mmHg diastolic but what is low blood pressure, exactly?
Your blood pressure needs to be high enough to do its job – supplying blood and providing vital oxygen to your limbs, organs and brain.
Cardiologist Michael Faulx, MD, explains, “A young healthy patient may have a resting blood pressure of 90/60 mmHg and feel absolutely fine.” On the other hand, “an older patient with an existing heart problem such as aortic stenosis (narrowing of the aortic valve) might feel weak and dizzy with a blood pressure of 115/70 mmHg.”
Why problems occur
Dr. Faulx explains, “Blood pressure depends on three things; stroke volume (amount of blood ejected from the heart per beat), heart rate and blood vessel tone (how clear and flexible your blood vessels are). Disorders that affect any of these three things can result in low blood pressure.”
Heart failure combined with low stroke volume can spell trouble if a person’s blood vessels are unable to respond properly in order to maintain adequate blood pressure. Excessively slow heart rate (bradycardia) also can result in dangerously low blood pressure.
Some conditions can impair blood vessel health and result in low blood pressure. Examples include infections (sepsis), paralysis (injury or stroke-related) and certain endocrine disorders such as low cortisol levels.
Medications are one of the most common reasons for too-low blood pressure.
Fluctuating blood pressure
Certain conditions called autonomic disorders cause the tone of the blood vessels and even the heart rate to fluctuate widely. As a result, blood pressure also fluctuates widely.
Medications can sometimes cause blood pressure to go up and down, particularly shorter-acting blood pressure medications that act fast, but result in a “rebound” increase in blood pressure and heart rate when they wear off.
When to call the doctor
Consult your doctor if you experience symptoms such as lightheadedness, fainting or feeling weak, as these symptoms might be related to too-low blood pressure.
Anyone who has existing kidney or liver problems, or anyone who has had a stroke or who might be at risk for stroke should have their blood pressure monitored carefully. Insufficient blood pressure could restrict critical blood supply to the organs and the brain.
Dr. Faulx assures the general public, “For otherwise healthy people, call your doctor if you have low blood pressure and you don’t feel well or have no energy. If you feel perfectly fine, then odds are your blood pressure, even if lower than average, is probably OK for you.”