Jane Teas

Dietary Seaweed Modifies Estrogen and Phytoestrogen Metabolism in Healthy Postmenopausal Women

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 = -2.29 x dose + 172.3; r = -0.70; P = 0.003), [corrected] 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:16alpha-hydroxyestrone (16alphaOHE(1)) (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. Seaweed favorably alters estrogen and phytoestrogen metabolism and these changes likely include modulation of colonic bacteria.

The Macrobiotic Diet in Cancer

Macrobiotics is one of the most popular alternative or complementary comprehensive lifestyle approaches to cancer. The centerpiece of macrobiotics is a predominantly vegetarian, whole-foods diet that has gained popularity because of remarkable case reports of individuals who attributed recoveries from cancers with poor prognoses to macrobiotics and the substantial evidence that the many dietary factors recommended by macrobiotics are associated with decreased cancer risk. Women consuming macrobiotic diets have modestly lower circulating estrogen levels, suggesting a lower risk of breast cancer. This may be due in part to the high phytoestrogen content of the macrobiotic diet. As with most aspects of diet in cancer therapy, there has been limited research evaluating the effectiveness of the macrobiotic diet in alleviating suffering or prolonging survival of cancer patients. The few studies have compared the experience of cancer patients who tried macrobiotics with expected survival rates or assembled series of cases that may justify more rigorous research. On the basis of available evidence and its similarity to dietary recommendations for chronic disease prevention, the macrobiotic diet probably carries a reduced cancer risk. However, at present, the empirical scientific basis for or against recommendations for use of macrobiotics for cancer therapy is limited. Any such recommendations are likely to reflect biases of the recommender. Because of its popularity and the compelling evidence that dietary factors are important in cancer etiology and survival, further research to clarify whether the macrobiotic diet or similar dietary patterns are effective in cancer prevention and treatment is warranted.

Walking Outside Improves Mood for Healthy Postmenopausal Women

Background Exercise has been shown to decrease breast cancer risk and slow the progression of breast cancer. Physician recommendations and clinical research data most often are for gym-based exercise programs. However, the importance of exercise location on mood and stress hormones that may influence adherence to exercise has not been addressed. Methods Women first walked for an hour outdoors along a university path and then a week later, for an hour indoors on a treadmill in a typical gym environment. Pre and post outdoor and indoor exercise moods (happy, pleased, sad, frustrated, worried, angry, delighted, and joy) were assessed by a 6 point Likert questionnaire, and saliva samples were collected for analysis of cortisol, and alpha amylase (a surrogate for serum norepinephrine). Results Nineteen healthy, non-smoking, postmenopausal women (average age 58 ± 4) participated. Compared with scores after walking outdoors, walking indoors was associated with higher scores of worry (p = 0.02; mean difference 0.9; 95% CI (0.17, 1.6) and frustration (p = 0.03; mean difference 0.9; 95% CI (0.12, 1.6), and lower scores for feelings of being pleased (p = 0.03; mean difference -0.8; 95% CI: -1.7, 0.1) and delighted (p = 0.05; mean difference -0.9; 95% CI: -1.75, -0.02). Changes in salivary hormone levels did not vary significantly between the two environments. Conclusion Walking outdoors was associated with improved mood, but walking indoors was not. Improved mood may reduce breast cancer risk indirectly by promoting regular exercise. Physician recommendations for exercise should include gym and non-gym based exercise options.

Serum IGF-1 Concentrations Change With Soy and Seaweed Supplements in Healthy Postmenopausal American Women

Insulin-like growth factor 1 (IGF-1) is an anabolic hormone important for growth and development. However, high-circulating serum concentrations in adults are associated with increased risk of postmenopausal breast cancer. Nutritional status and specific foods influence serum IGF-1 concentrations. Breast cancer incidence is typically low in Asian countries where soy is commonly consumed. Paradoxically, soy supplement trials in American women have reported significant increases in IGF-1. Seaweed also is consumed regularly in Asian countries where breast cancer risk is low. We investigated the possibility that seaweed could modify soy-associated increases in IGF-1 in American women. Thirty healthy postmenopausal women (mean age 58 yr) participated in this 14-wk double-blinded, randomized, placebo-controlled crossover clinical trial. Participants consumed 5 g/day placebo or seaweed (Alaria esculenta) in capsules for 7 wk. During the 7th wk, a high-soy protein isolate powder was added (2 mg/kg body weight aglycone equivalent isoflavones). Overnight fasting blood samples were collected after each intervention period. Soy significantly increased serum IGF-1 concentrations compared to the placebo (21.2 nmol/L for soy vs. 16.9 nmol/L for placebo; P = 0.0001). The combination of seaweed and soy significantly reduced this increase by about 40% (21.2 nmol/L for soy alone vs. 19.4 nmol/L; P = 0.01). Concurrent seaweed and soy consumption may be important in modifying the effect of soy on IGF-1 serum concentrations.

Nutrient Composition and Anti-inflammatory Potential of a Prescribed Macrobiotic Diet

Despite nutrient adequacy concerns, macrobiotic diets are practiced by many individuals with cancer and other life-threatening illnesses. This study compared the nutrient composition and inflammatory potential of a macrobiotic diet plan with national dietary recommendations and intakes from a nationally representative sample. Nutrient comparisons were made using the 1) macrobiotic diet plan outlined in the Kushi Institutes Way to Health; 2) recommended dietary allowances (RDA); and 3) National Health and Nutrition Examination Survey (NHANES) 2009–2010 data. Comparisons included application of the recently developed dietary inflammatory index (DII). Analyses focused on total calories, macronutrients, 28 micronutrients, and DII scores. Compared to NHANES data, the macrobiotic diet plan had a lower percentage of energy from fat, higher total dietary fiber, and higher amounts of most micronutrients. Nutrients often met or exceeded RDA recommendations, except for vitamin D, vitamin B12, and calcium. Based on DII scores, the macrobiotic diet was more anti-inflammatory compared to NHANES data (average scores of −1.88 and 1.00, respectively). Findings from this analysis of a macrobiotic diet plan indicate the potential for disease prevention and suggest the need for studies of real-world consumption as well as designing, implementing, and testing interventions based on the macrobiotic approach.