Lactopeptides and human blood pressureGeleijnse, Johanna M; Engberink, Marielle FCurrent Opinion in Lipidology: February 2010 - Volume 21 - Issue 1 - p 58–63 doi: 10.1097/MOL.0b013e3283333813 Nutrition and metabolism: Edited by Paul Nestel and Ronald P. Mensink Abstract Author Information Purpose of review Since the mid-1990s, a number of randomized controlled trials have been published that showed an antihypertensive effect of peptides derived from milk. Research has mainly focused on isoleucine-proline-proline and valine-proline-proline (IPP + VPP), two lactotripeptides that can inhibit the angiotensin-converting enzyme (ACE) in vitro. In Finnish and Japanese subjects with (mild) hypertension, systolic blood pressure (SBP) reductions of approximately 5 mmHg were reported during 4–12 weeks of IPP + VPP supplementation. This review was performed to summarize new data from human intervention studies. Recent findings The effect of lactotripeptides on blood pressure has recently been examined in six double-blind, placebo-controlled trials that involved a total of 780 subjects with high-normal blood pressure or untreated hypertension from the UK and The Netherlands. Intervention periods lasted 4–8 weeks, and IPP + VPP intake ranged from 2 to 10 mg/day. Contrary to earlier trials, there was little evidence for an antihypertensive effect of IPP + VPP. Furthermore, no ACE inhibition was observed in vivo. Summary Recent data do not support a role for lactotripeptides in blood pressure regulation. However, we cannot exclude a beneficial effect in hypertensive subjects from specific populations (e.g. Finland, Japan). Should this be confirmed, more research is needed on mechanisms other than the renin-angiotensin-aldosterone system that could be involved. Division of Human Nutrition, Wageningen University, The Netherlands Correspondence to Dr Johanna M. Geleijnse, Division of Human Nutrition, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands Tel: +31 317 482574; fax: +31 317 483342; e-mail: firstname.lastname@example.org © 2010 Lippincott Williams & Wilkins, Inc.