A new study in The American Journal of Clinical Nutrition confirms recent evidence that increasing protein intake to 25 percent of your diet can decrease blood pressure and should be a first line of defense when trying to lower blood pressure. Boosting protein intake may also improve body composition by increasing muscle mass and reducing body fat.
The new study lasted four weeks and compared the effect of giving individuals with high blood pressure an extra 60 grams of protein a day in supplement form or the same amount of supplementary carbs. At the start of the study, the average blood pressure of all participants was 143 mmHg for systolic and 92 for diastolic blood pressure. None were on blood pressure lowering medications. Both groups ate the same diet of 15 percent protein, 30 percent fat, and 55 percent carbs.
The protein group was then given an additional 20 grams of protein three times a day in a drink, bringing the total daily protein intake up to 25 percent of the diet with the carb intake dropping to 45 percent. The other group was given an additional 20 grams three times a day of carbs from maltodextrin.
After four weeks, the protein group decreased the average systolic blood pressure reading by 4.9 mm Hg and the diastolic by 2.7 mm Hg compared to no change in the group that received supplementary carbs. This drop in blood pressure is substantial and clinically significant since studies that test blood pressure lowering drugs look for a drop in systolic blood pressure of between 0.8 and 2 mm Hg to be relevant. A 2 mm Hg drop in systolic blood pressure can significantly reduce the risk of heart disease, heart attack, and stroke.
The impressive decrease of nearly 5 mm Hg has been shown to lower risk of stroke by at least 14 percent and mortality from heart disease by 9 percent. It will also lower the risk of a non-fatal heart attack by nearly 25 percent!
Researchers suggest a high-protein diet lowers blood pressure because it improves the overall function of blood vessels, allowing them to dilate and decrease pressure more effectively. Elevated blood pressure means that more pressure is necessary to move blood through the blood vessels, which can damage them over time and lead to heart disease.