Prospective controlled research on red meat, haem iron, and blood pressure
The recent report of Tzoulaki and colleagues  on a large cross-
sectional epidemiological international collaborative study on macro-
/micronutrients and blood pressure (INTERMAP) indicated that blood
pressure was negatively associated with non-haem iron ingestion and
positively associated with red meat intake. Both this paper and the
accompanying editorial noted the need for confirmation of such findings
with prospective controlled studies. I am writing to draw attention to a
relevant small, but well-controlled prospective study from our laboratory.
We reported no change in the systolic or diastolic resting blood
pressure of 21 healthy premenopausal women who consumed weighed
experimental lacto-ovo-vegetarian and meat-containing diets (with
equivalent food energy) for 8 wk each in a randomized cross-over design
. These two diets contained 0 and 184 g meat/d, respectively. Three-
quarters of this meat was beef, with chicken as the remainder. As
described in a subsequent paper emphasizing iron content and
absorption/bioavailability , the two diets contained 12.6 and 13.6 mg
total iron, and 0 and 1.2 mg haem iron/d, respectively. Compared to the
meat-containing diet, the lacto-ovo-vegetarian diet resulted in
substantially lower non-haem and total iron absorption . This small
study with controlled diets for 8 wk each does not support a positive
association of red meat or haem iron intake with blood pressure, under
conditions of equivalent energy consumption.
 Tzoulaki I, Brown IJ, Chan Q, Van Horn L, Ueshima H, Zhao L, et
al. Relation of iron and red meat intake to blood pressure: cross
sectional epidemiological study. Bmj 2008;337:a258.
 Hunt JR, Matthys LA, Johnson LK. Zinc absorption, mineral
balance, and blood lipids in women consuming controlled lactoovovegetarian
and omnivorous diets for 8 wk. Am J Clin Nutr 1998;67:421-430.
 Hunt JR, Roughead ZK. Nonheme-iron absorption, fecal ferritin
excretion, and blood indexes of iron status in women consuming controlled
lactoovovegetarian diets for 8 wk. Am J Clin Nutr 1999;69:944-52.
Author has received some research funding from the National Cattlemen's Beef Association in the USA.
Competing interests: No competing interests