TY - JOUR
T1 - Plasma phytoestrogens are not altered by probiotic consumption in postmenopausal women with and without a history of breast cancer
AU - Nettleton, Jennifer A.
AU - Greany, Kristin A.
AU - Thomas, William
AU - Wangen, Kerry E.
AU - Adlercreutz, Herman
AU - Kurzer, Mindy S.
PY - 2004/8
Y1 - 2004/8
N2 - Soy phytoestrogens were suggested to reduce the risk of a number of diseases including breast cancer. Given that these compounds are metabolized by bacteria, alteration of intestinal bacteria and enzymes may affect phytoestrogen metabolism. We hypothesized that probiotics, when consumed with soy protein, would increase plasma isoflavones, as well as equol producer frequency, in postmenopausal women. We further hypothesized that these effects would differ between women who have had breast cancer and women who have not. To test these hypotheses, 20 breast cancer survivors and 20 controls completed four 6-wk treatments in a randomized, crossover design: supplementation with soy protein (S) (26.6 ± 4.5 g protein, 44.4 ± 7.5 mg isoflavones/d); soy + probiotics (S+P) (109 colony-forming units Lactobacillus acidophilus DDS + 1 and Bifidobacterium longum, 15-30 mg fructooligosaccharide/d); milk protein (M) (26.6 ± 4.5 g protein/d); and milk + probiotics (M+P). Plasma phytoestrogen concentrations did not differ between controls and survivors, although genistein tended to be lower in survivors at baseline (P = 0.15), and during soy (P = 0.16) and milk protein (P = 0.16) consumption. As expected, soy consumption increased plasma phytoestrogen concentrations (P < 0.0001). Plasma phytoestrogen concentrations and the number of equol producers did not differ between the S and S+P diets. At the same time, plasma equol concentrations as well as urinary equol excretion in 2 subjects were more than 7-fold different between the 2 diets. These results indicate that this particular probiotic supplement does not generally affect plasma isoflavones, although the large differences between plasma and urinary equol in some subjects suggest that equol producer status may be modifiable in some individuals.
AB - Soy phytoestrogens were suggested to reduce the risk of a number of diseases including breast cancer. Given that these compounds are metabolized by bacteria, alteration of intestinal bacteria and enzymes may affect phytoestrogen metabolism. We hypothesized that probiotics, when consumed with soy protein, would increase plasma isoflavones, as well as equol producer frequency, in postmenopausal women. We further hypothesized that these effects would differ between women who have had breast cancer and women who have not. To test these hypotheses, 20 breast cancer survivors and 20 controls completed four 6-wk treatments in a randomized, crossover design: supplementation with soy protein (S) (26.6 ± 4.5 g protein, 44.4 ± 7.5 mg isoflavones/d); soy + probiotics (S+P) (109 colony-forming units Lactobacillus acidophilus DDS + 1 and Bifidobacterium longum, 15-30 mg fructooligosaccharide/d); milk protein (M) (26.6 ± 4.5 g protein/d); and milk + probiotics (M+P). Plasma phytoestrogen concentrations did not differ between controls and survivors, although genistein tended to be lower in survivors at baseline (P = 0.15), and during soy (P = 0.16) and milk protein (P = 0.16) consumption. As expected, soy consumption increased plasma phytoestrogen concentrations (P < 0.0001). Plasma phytoestrogen concentrations and the number of equol producers did not differ between the S and S+P diets. At the same time, plasma equol concentrations as well as urinary equol excretion in 2 subjects were more than 7-fold different between the 2 diets. These results indicate that this particular probiotic supplement does not generally affect plasma isoflavones, although the large differences between plasma and urinary equol in some subjects suggest that equol producer status may be modifiable in some individuals.
KW - Plasma isoflavones
KW - Probiotic
KW - Soy
UR - http://www.scopus.com/inward/record.url?scp=3543107867&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=3543107867&partnerID=8YFLogxK
U2 - 10.1093/jn/134.8.1998
DO - 10.1093/jn/134.8.1998
M3 - Article
C2 - 15284389
AN - SCOPUS:3543107867
SN - 0022-3166
VL - 134
SP - 1998
EP - 2003
JO - Journal of Nutrition
JF - Journal of Nutrition
IS - 8
ER -