Also see:
Ray Peat, PhD on the Benefits of the Raw Carrot
Dietary Fiber, Bowel Health, and Cancer
Hormonal profiles in women with breast cancer
Endometriosis and Estrogen
The effect of raw carrot on serum lipids and colon function
Protective Bamboo Shoots
Endotoxin-lipoprotein Hypothesis
Endotoxin: Poisoning from the Inside Out
Protection from Endotoxin
Bowel Toxins Accelerate Aging
Protective Cascara Sagrada and Emodin
Fermentable Carbohydrates, Anxiety, Aggression
Intestinal Serotonin and Bone Loss
Autoimmunity and Intestinal Flora
“Undigestible fiber, if it isn’t broken down by bowel bacteria, increases fecal bulk, and tends to speed the transit of material through the intestine, just as laxatives do. But some of these “fiber” materials, e.g., lignin, are themselves estrogenic, and other fibers, by promoting bacterial growth, can promote the conversion of harmless substances into toxins and carcinogens. When there is a clear “antiestrogen” effect from dietary fiber, it seems to be the result of accelerated transit through the intestine, speeding elimination and preventing reabsorption of the estrogen which has been excreted in the bile. Laxatives have this same effect on the excretion of estradiol.” -Ray Peat, PhD
Accelerated bowel transit time reduced estrogen:
Br J Cancer. 1997;76(3):395-400.
Lower serum oestrogen concentrations associated with faster intestinal transit.
Lewis SJ, Heaton KW, Oakey RE, McGarrigle HH.
Increased fibre intake has been shown to reduce serum oestrogen concentrations. We hypothesized that fibre exerts this effect by decreasing the time available for reabsorption of oestrogens in the colon. We tested this in volunteers by measuring changes in serum oestrogen levels in response to manipulation of intestinal transit times with senna and loperamide, then comparing the results with changes caused by wheat bran. Forty healthy premenopausal volunteers were placed at random into one of three groups. The first group took senna for two menstrual cycles then, after a washout period, took wheat bran, again for two menstrual cycles. The second group did the reverse. The third group took loperamide for two menstrual cycles. At the beginning and end of each intervention a 4-day dietary record was kept and whole-gut transit time was measured; stools were taken for measurement of pH and beta-glucuronidase activity and blood for measurement of oestrone and oestradiol and their non-protein-bound fractions and of oestrone sulphate. Senna and loperamide caused the intended alterations in intestinal transit, whereas on wheat bran supplements there was a trend towards faster transit. Serum oestrone sulphate fell with wheat bran (mean intake 19.8 g day(-1)) and with senna; total- and non-protein-bound oestrone fell with senna. No significant changes in serum oestrogens were seen with loperamide. No significant changes were seen in faecal beta-glucuronidase activity. Stool pH changed only with senna, in which case it fell. In conclusion, speeding up intestinal transit can lower serum oestrogen concentrations.
Eur J Gastroenterol Hepatol. 1998 Jan;10(1):33-9.
Intestinal absorption of oestrogen: the effect of altering transit-time.
Lewis SJ, Oakey RE, Heaton KW.
OBJECTIVE:
The mechanism by which a high fibre diet may reduce serum oestrogens is unknown. We hypothesized that time is a rate-limiting factor in oestrogen absorption from the colon so that changes in colonic transit-rate affect the proportion of oestrogen that is deconjugated and/or absorbed.
AIM:
To determine if alteration of intestinal transit rate would influence the absorption of an oral dose of oestradiol glucuronide.
PARTICIPANTS:
Twenty healthy postmenopausal women recruited by advertisement.
SETTING:
Department of Medicine, Bristol Royal Infirmary.
METHODS:
Volunteers consumed, in turn, wheat bran, senna, loperamide and bran shaped plastic flakes, each for 10 days with a minimum 2 week washout period between study periods, dietary intake being unchanged. Before and in the last 4 days of each intervention whole-gut transit-time, defecation frequency, stool form, stool beta-glucuronidase activity, stool pH and the absorption of a 1.5 mg dose of oestradiol glucuronide were measured.
RESULTS:
Wheat bran, senna and plastic flakes led to the intended reduction in whole-gut transit-time, increase in defecatory frequency and increase in stool form score. Loperamide caused the opposite effect. The length of time the absorbed oestrogen was detectable in the serum fell with wheat bran and senna, although this was only significant for oestradiol. Oestrone, but not oestradiol, was detectable for a longer time with loperamide. Plastic flakes had no effect on either oestrogen. Areas under the curve did not change significantly but tended to fall with the three transit-accelerating agents and to rise with loperamide.
CONCLUSION:
Our data indicate there is likely to be an effect of intestinal transit on the absorption of oestrogens but more refined techniques are needed to characterize this properly.
Estrogen slows bowel transit time:
Res Nurs Health. 1998 Jun;21(3):221-8.
Estrogen suppresses gastric motility response to thyrotropin-releasing hormone and stress in awake rats.
Bond EF, Heitkemper MM, Bailey SL.
Symptoms associated with gastric motility alteration vary with stress and ovarian hormone status, most notably in women with irritable bowel syndrome. This study examines combined effects, comparing gastric motility during administration of a stress-related neuropeptide thyrotropin-releasing hormone (TRH) and restraint stress in conscious rats of varied ovarian hormone status. Adult rats were ovariectomized and implanted with estrogen, progesterone, or vehicle-releasing pellets. After 21 days, intracerebroventricular (i.c.) cannula and gastric tension transducer were implanted. After 25-27 days, motility was recorded during neuropeptide injection (TRH/saline i.c.) or restraint stress. TRH induced increased motility in all groups; the response varied with hormone group, and was least and briefest in estrogen-treated rats. Motility during restraint varied with hormone group; it was diminished in estrogen-treated but not other groups. Ovarian hormone status (estrogen) modifies gut response to TRH and restraint stress.
Intestinal flora, diet, and estrogen:
Rev Infect Dis. 1984 Mar-Apr;6 Suppl 1:S85-90.
Estrogens, breast cancer, and intestinal flora.
Gorbach SL.
Epidemiologic evidence has linked diet to breast cancer, with the highest cancer rates observed in women who eat a high fat-low fiber diet. There is also substantial information, both clinical and experimental, that implicates estrogens in the etiology of breast cancer. A recent study from our laboratory has shown that diet influences levels of estrogens, and the main mechanism is metabolism of estrogens in the intestine. The intestinal microflora plays a key role in the enterohepatic circulation of estrogens by deconjugating bound estrogens that appear in the bile, thereby permitting the free hormones to be reabsorbed. By suppressing the microflora with antibiotic therapy, fecal estrogens increase and urinary estrogens decrease, changes indicating diminished intestinal reabsorption. A low fat-high fiber diet is associated with similar findings-high fecal estrogens and low urinary estrogens. It appears that the microflora plays a key role in the metabolism of female sex hormones.
