The Japanese, particularly those who live in the rural coastal areas of Japan, are noted for having luxurious heads of hair that remain dark well into old age. There may be a dietary component to this phenomena. It would appear that the concurrent consumption of Seaweed in its various forms with Soy significantly increases the production of equol in equol producers, and facilitates the production of equol in those that were previously non equol producers. In one small case study of two equol non-producers, both were converted into being equol producers with the addition of seaweed to soy isoflavones. Seaweeds, due to their iodine content are also useful for regulating thyroid function. It has been observed that iodine deficiency in the diet causes dryness, thinness and poor growth of hair. Both underactive and overactive thyroid function is implicated in Androgenetic and other forms of hair loss.
Seaweed can be easily obtained in any Asian Market in various forms. One study stated the mere consumption of 5 grams produced these effects. A small sheet of Nori, a palatable common seaweed used in wrapping sushi, well exceeds this dose and can be easily singularly consumed.
Seaweed, Soy, and Estrogen Metabolism in Healthy Postmenopausal American Women.
Jane Teas, Mindy Kurzer, Thomas Hurley, Christopher Longcope and James R. Hebert
University of South Carolina, Columbia, SC, University of Minnesota, Minneapolis, MN, University of Massachusetts, Worcester, MA
Introduction: Seaweed and soy foods are common in Japan and Korea where the incidence and mortality of breast cancer are significantly lower than in the US. Most attention has focused on soy foods and their phytoestrogen content. Seaweeds are known to have an antibiotic effect in vitro and in vivo studies support the idea that dietary seaweed modifies gastrointestinal bacteria populations. We investigated the possibility that dietary seaweed could act as a probiotic when consumed with soy, and enhance the gastrointestinal metabolism of phytoestrogens, especially the increasing the production of equol. Equol production is associated with decreased breast cancer risk. Methods: In a double-blinded placebo-controlled clinical trial, 28 healthy postmenopausal women (average age = 58 years) were recruited to our 17 week study. Ten of the women had been treated for early breast cancer but were disease free at the time of the study. None of the women took antibiotics during the study, and alcoholic beverage consumption was limited to one or fewer drinks per week. The women were randomized to either seaweed or placebo for six weeks, followed by a week when soy supplementation (2 mg. isoflavones/kg body weight) was added. A 3-week washout period separated the two arms of the study, after which women were crossed over to the alternate intervention arm. Blood samples for estradiol, estrone, and sex hormone binding globulin were obtained at baseline and each of the 6 clinic endpoints. Women collected 48-hour urine specimens at each of the 7 time points for phytoestrogen determination.
Results: Blood levels of estrone and estradiol did not change during the study, but SHBG levels significantly decreased during the seaweed plus soy supplementation period. No urinary phytoestrogen excretion was reported during the placebo or seaweed interventions, but urinary phytoestrogens were detected during both the soy and seaweed plus soy intervention periods. Equol production was only seen in women who had never been treated for breast cancer, and not in any of the breast cancer survivors. For 6 of the 7 disease-free women who produced equol when taking soy, the combination of seaweed plus soy further increased equol levels. Conclusions: The presence of seaweed in the Asian diet may act as a probiotic, enhancing intestinal conversion of phytoestrogens, particularly the production of equol, and could account for some of the breast cancer protective effects of dietary soy.
Dietary Seaweed Modifies Estrogen and Phytoestrogen Metabolism in Healthy Postmenopausal Women
Jane Teas, Thomas G. Hurley, James R. Hebert, Adrian A. Franke, Daniel W. Sepkovic and Mindy S. Kurzer
University of South Carolina Cancer Center, Columbia, SC 29208; South Carolina Statewide Cancer Prevention and Control Program, Columbia, SC 29208; Department of Biostatistics and Epidemiology, Arnold School of Public Health, Cancer Research Center of Hawai’i, University of Hawai’i, Honolulu, HI 96813; Hackensack University Medical Center, Hackensack, NJ 07601; Department of Medicine, New Jersey Medical School, University of Medicine and Dentistry, Newark, NJ 07601; and Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN 55108
Seaweed and soy foods are consumed daily in Japan, where breast cancer rates for postmenopausal women are significantly lower than in the West. Likely mechanisms include differences in diet, especially soy consumption, and estrogen metabolism. Fifteen healthy postmenopausal women participated in this double-blind trial of seaweed supplementation with soy challenge. Participants were randomized to 7 wk of either 5 g/d seaweed (Alaria) or placebo (maltodextrin). During wk 7, participants also consumed a daily soy protein isolate (2 mg isoflavones/kg body weight). After a 3-wk washout period, participants were crossed over to the alternate supplement schedule. There was an inverse correlation between seaweed dose (mg/kg body weight) and serum estradiol (E2) (seaweed-placebo = y = 0.28 x dose � 42.8; r = 0.70; P = 0.003), which was linear across the range of weights. Soy supplementation increased urinary daidzein, glycitein, genistein, and O-desmethylangolensin (P = 0.0001) and decreased matairesinol and enterolactone (P < 0.05). Soy and seaweed plus soy (SeaSoy) increased urinary excretion of 2-hydroxyestrogen (2-OHE) (P = 0.0001) and the ratio of 2-OHE:16 -hydroxyestrone (16 OHE1) (P = 0.01). For the 5 equol excretors, soy increased urinary equol excretion (P = 0.0001); the combination of SeaSoy further increased equol excretion by 58% (P = 0.0001). Equol producers also had a 315% increase in 2:16 ratio (P = 0.001) with SeaSoy.