Background: The consumption of milk products has been shown to lower cholesterol. The mechanism of action surrounding this observation has been attributed to the protein fraction of milk and serum.
Objective: We examined the effect of an oral serum bovine immunoglobulin protein fraction (bIg) derived from US Department of Agriculture-approved beef (aged <30 mo) on lipid indexes in humans.
Design: Participants included men and women (aged 25-70 y) with hypercholesterolemia (5.44-6.99 mmol/L) who were not receiving cholesterol-lowering medication. Treatment consisted of the randomized, double-blind, parallel-group, placebo-controlled administration of 5 g bIg for 6 wk in 52 participants (n = 26 each in treatment and control groups).
Results: Mean (+/-SD) total cholesterol (TC) at baseline was 6.33 +/- 0.1 mmol/L for bIg and 6.16 +/- 0.1 mmol/L for placebo. A repeated-measures multivariate analysis of covariance covaried for change in total energy and alcohol intake and Tukey's post hoc examination of our data showed that the bIg-treated group had a significant reduction in TC at 3 wk (5.98 +/- 0.5 mmol/L; P < 0.05) and 6 wk (5.97 +/- 0.7 mmol/L; P < 0.05). The concentration at 6 wk was significantly different from that in the placebo group (P < 0.05). This reduction was largely due to a decrease in LDL cholesterol in the bIg-treated group from baseline (4.12 +/- 0.6 mmol/L) at 3 wk (3.92 +/- 0.7 mmol/L, P < 0.05) and at 6 wk (3.84 +/- 0.6 mmol/L, P < 0.05); the 6-wk concentration differed significantly between the treatment and placebo groups (P < 0.05). We observed no significant changes in the placebo group or in any other lipid indexes or markers associated with hepatorenal or cardiovascular function.
Conclusion: Consumption of bIg appears to positively modulate the primary lipid indexes associated with cardiovascular disease.