Machin DR, Park W, Alkatan M, Mouton M, Tanaka H. - 45445 N - Am J Clin Nutr 2014 ; 100(1) : 80-87.

Hypotensive effects of solitary addition of conventional nonfat dairy products to the routine diet: a randomized controlled trial

BACKGROUND: The high consumption of low-fat and nonfat dairy products is associated with reduced risk of high blood pressure.

OBJECTIVE: We aimed to investigate whether the solitary addition of nonfat dairy products to the normal routine diet was capable of lowering blood pressure in middle-aged and older adults with elevated blood pressure.

DESIGN: With the use of a randomized, crossover intervention-study design, 49 adults (56% women) with elevated blood pressure (mean +/- SEM age: 53 +/- 2 y; systolic blood pressure: 135 +/- 1; diastolic blood pressure: 80 +/- 1 mm Hg) underwent a high-dairy condition (+4 servings conventional nonfat dairy products/d) and isocaloric no-dairy condition (+4 servings fruit products/d) in which all dairy products were removed. Both dietary conditions lasted 4 wk with a 2-wk washout before crossing over into the alternate condition.

RESULTS: The high-dairy condition produced reductions in systolic blood pressure (135 +/- 1 to 127 +/- 1 mm Hg) and pulse pressure (54 +/- 1 to 48 +/- 1 mm Hg) (both P < 0.05). The hypotensive effects were observed within 3 wk after the initiation of the dietary intervention and in both casual seated and ambulatory (24-h) measurements (P < 0.05). Pulse pressure was increased after the removal of all dairy products in the no-dairy condition (54 +/- 1 to 56 +/- 1 mm Hg; P < 0.05). There were no changes in diastolic blood pressure after either dietary condition.

CONCLUSION: We concluded that the solitary manipulation of conventional dairy products in the normal routine diet would modulate blood pressure in middle-aged and older adults with prehypertension and hypertension. This trial was registered at clinicaltrials.gov as NCT01577030.