Functional food is a term to describe a specific food or food components that have specific effects in our bodies. It’s a bit of a misnomer since food IS the building block of our bodies, and so effects almost every aspect of our health. Blood pressure is one aspect of our health that responds quite favorably to changes in our dietary intake. This study published November 6, in the British Journal of Nutrition, illustrates how grape seed extract can lower blood pressure. Subjects were given a grape seed extract containing beverage to drink twice daily for 6 weeks. Test subjects with pre-hypertension (borderline high blood pressure), reduced their systolic and diastolic blood pressures by 5.6% and 4.7%, respectively. Interestingly, those with higher blood pressure experienced almost twice the blood pressure lowering benefit. The amount of grape seed extract used in the study was 150 mg, twice daily (300 mg/day), easily found in an over the counter supplement.
But you don’t have to take pills. Simply eating more vegetables, legumes, and fruit can significantly lower blood pressure, so much so that vegetarians and vegans have almost no risk of developing high blood pressure. How does this work? The compounds in plant foods help make nitric oxide in the blood vessels which relaxes the muscles that line the arteries. Yes, you have muscles in your arteries! These ‘smooth muscles’ as we call them, like nitric oxide and minerals, particularly magnesium. Legumes, whole grains, nuts and seeds are good sources of magnesium, so a diet high in plants naturally lowers blood pressure.
Researchers have described another functional food, flax seed, as having ‘one of the most potent antihypertensive effects achieved by a dietary intervention.’ In a study published in 2013 in Hypertension, just 30 g of flax seed daily for 6 months reduced systolic (the top number) pressure by 10 mm Hg, and diastolic (the bottom number) by 7 mm Hg. That’s enough to push a person with high blood pressure into the normal blood pressure range. Thirty grams of flax seed is 4 Tbsp. which may be a lot for some to eat everyday. But remember, in the study, they didn’t encourage any other dietary changes. So a more practical daily routine might include 2 Tbsp. of flax seed, 1/2 cup beans or whole grain like quinoa, a cup of blueberries and some hibiscus tea. Yes, you can drink functional food blood pressure lowering compounds too. This study in Fitoterapia found hibiscus tea to be as effective as a common blood pressure medication, and published in the Journal of Nutrition, researchers Diana McKay, et al, found just 3 cups of hibiscus tea to lower systolic pressure by 7 mm Hg.
Want more evidence? Just complete your own search on PubMed on functional foods and hypertension. And don’t forget to check your blood pressure…high blood pressure is a risky business!