Dear Dr. Roach: As a 72-year-old man with mildly elevated blood pressure (averaging 135/77), I’m very interested in lowering my blood pressure without resorting to medications. My research reveals that virtually all blood pressure medications have considerable side effects, and physicians often prescribe more than one.
My weight is appropriate for my height (184 pounds; 6 feet, 3 inches tall). I mainly eat a plant-based diet and do science-based weight training three times a week as well as cardio three times a week. I also stay active with hiking, climbing and skiing.
Recently, I’ve begun doing inspiratory muscle training (IMT). With IMT, you inhale through a device that restricts airflow, to make inhaling more challenging. This is done once a day for 30 inhalations.
Although this technique has a bogus ring to it, there seems to be credible studies that suggest it has merit in improving blood pressure, as well as benefiting one’s endothelial health and overall cardiovascular well-being.
What are your thoughts on IMT?
Dear Anon.: Several studies have now shown that 5 minutes of IMT, done five to seven days a week, reduces blood pressure by about 7 mmHg systolic and 2 mmHg diastolic in people with elevated blood pressure. The improvements in blood pressure started to occur within two weeks.
The C-reactive protein, a measure of inflammation, decreased in participants of the study who underwent IMT. Additionally, as you correctly state, there were other benefits seen by sophisticated tests on the cells lining the blood vessels (the endothelium), those of which have unclear benefits to living humans.
These are not large benefits, but they are in the range of what we typically find with some blood pressure medicines and are enough to reduce heart disease and stroke risk in many trials. At the very least, this may allow some people to be treated with fewer medications or at lower dosages.
While I agree with you that it seems almost too good to be true, the evidence so far is that there is benefit without much cost. Other non-drug treatments to help reduce blood pressure include salt restriction and relaxation techniques, such as mindfulness.
Dear Dr. Roach: Regarding your column in response to iron deficiency possibly caused by drinking tea, I was wondering if that only applied to caffeinated tea and coffee? I drink lots of herbal iced tea with no sweeteners.
Dear A.V.: No, it’s the tannins in tea, not the caffeine, that decrease absorption of iron. I wish I had emphasized in the initial column that tea does not inhibit the absorption of iron in the form of heme, found in meat, which is where most Americans get most of their iron. Tannins reduce absorption of non-heme iron, found in whole grains, nuts, seeds, legumes and leafy greens.
Most herbal teas do not have tannins. Camellia sinensis, the tea plant, contains tannins. A few herbal teas, such as those containing hibiscus, do have tannins in small amounts. Several people also asked me about wine, which often contains tannins. Red wine also has the same effect of binding non-heme iron and reduces its absorption by about half.
Readers may email questions to ToYourGoodHealth@med.cornell.edu.