21 research outputs found
The consumption of seaweed as a protective factor in the etiology of breast cancer: proof of principle
Dietary exposures and oral precancerous lesions in Srikakulam District, Andhra Pradesh, India
Objective: To test the effect of dietary nutrients on oral precancerous lesions in a reverse-smoking (i.e. smoking with the glowing end inside the mouth) population in South India. Design: Case–control. Cases with precancerous lesions were matched to an equal number of lesion-free controls matched on age (^5 years), sex and village. All subjects used tobacco in some form. Dietary data were obtained using an intervieweradministered food-frequency questionnaire, designed for use in this population. All interviews were conducted blinded to the disease status of the subject. Data were analysed using logistic regression. Setting: Nineteen rural villages in Srikakulam District, Andhra Pradesh. Subjects: From a survey of 6007 tobacco users, 485 (79% women) were found to have precancerous, mostly palatal, lesions (cases), and 487 lesion-free subjects were selected as controls. Results: All eligible subjects consented to participate and nearly all (.99%) had complete data for analyses. Reverse smoking was the most common form of tobacco use among cases (81.9%) and controls (73.5%), and reverse smokers were 5.19 times more likely than chewers to have these lesions (95 % confidence interval 1.35, 19.9). After controlling for relevant covariates, including the type of tobacco use, protective linear effects were observed for zinc (70% reduction across the interquartile range, P , 0:002), calcium (34% reduction, P , 0:002), fibre (30% reduction, P , 0:009), riboflavin (22% reduction, P , 0:03) and iron (17% reduction, P , 0:05). Conclusions: Several dietary nutrients appear to protect against oral precancerous lesions that are strongly associated with reverse smoking. The results of this study indicate scope for targeting dietary factors in preventing oral cancer, which should be coupled with aggressive anti-tobacco use efforts
Seaweed and Soy: Companion Foods in Asian Cuisine and Their Effects on Thyroid Function in American Women
Seaweeds and soy are two commonly eaten foods in Asia. Both have been reported to affect thyroid function, seaweed because of its iodine content and soy because of its goitrogenic effect. Twenty-five healthy postmenopausal women (mean age 58 years) completed a double-blinded randomized crossover study. Ten capsules (5 g/day) of placebo or seaweed (Alaria exculenta), providing 475 ug of iodine/day, were consumed daily for 7 weeks. A powdered soy protein isolate (Solae Co., St. Louis, MO) providing 2 mg of isoflavones/kg of body weight, was given daily during the last week of each treatment arm. On average, this provided 141.3 mg of isoflavones/day and 67.5 g of protein/day. Blood samples and 48-hour urine samples were collected before and after each intervention period, and urinary I/C (ug of iodine/g of creatinine) and serum thyroxine, free thyroxine index, total triiodothyronine, and thyroidstimulating hormone (TSH) were measured. Seaweed ingestion increased I/C concentrations (P \u3c .0001) and serum TSH (P \u3c .0001) (1.69 +/- 0.22 vs. 2.19 +/- 0.22 uU/mL, mean +/- SE). Soy supplementation did not affect thyroid end points. Seven weeks of 5 g/day seaweed supplementation was associated with a small but statistically significant increase in TSH. Soy protein isolate supplementation was not associated with changes in serum thyroid hormone concentrations
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
The consumption of seaweed as a protective factor in the etiology of breast cancer: proof of principle
Daily consumption of seaweed has been proposed as a factor in explaining lower postmenopausal breast cancer (BC) incidence and mortality rates in Japan. This clinical trial assessed the impact of introducing seaweed- to non-seaweed-consuming American postmenopausal women. Fifteen healthy postmenopausal women were recruited for a 3-month single-blinded placebo controlled clinical trial; five had no history of BC (controls) and ten were BC survivors. Participants ingested ten capsules daily (5 g day(−1)) of placebo for 4 weeks, seaweed (Undaria) for 4 weeks, then placebo for another 4 weeks. Blood and urine samples were collected after each treatment period. Urinary human urokinase-type plasminogen activator receptor concentrations (uPAR) were analyzed by ELISA, and urine and serum were analyzed for protein expression using surface-enhanced laser desorption/ionization–time-of-flight mass spectrometry (SELDI-TOF-MS). Urinary creatinine standardized uPAR (in pg mL μg(−1) creatinine) changed significantly between groups, decreasing by about half following seaweed supplementation (placebo 1, 1.5 (95 % CI, 0.9–2.1) and seaweed, 0.9 (95 % CI, 0.6–1.1) while placebo 2 returned to pre-seaweed concentration (1.7 (95 % CI, 1.2-2.2); p = 0.01, ANOVA). One SELDI-TOF-MS-identified urinary protein (m/z 9,776) showed a similar reversible decrease with seaweed and is reported to be associated with cell attachment. One serum protein (m/z 8,928) reversibly increased with seaweed and may be the immunostimulatory complement activation C3a des-arginine. uPAR is higher among postmenopausal women generally, and for BC patients, it is associated with unfavorable BC prognosis. By lowering uPAR, dietary seaweed may help explain lower BC incidence and mortality among postmenopausal women in Japan
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
Nutritional and socioeconomic factors in relation to prostate cancer mortality: a cross-national study
BACKGROUND: Large international variations in rates of prostate cancer incidence and mortality suggest that environmental factors have a strong influence on the development of this disease. The purpose of this study was to identify predictive variables for prostate cancer mortality in data from 59 countries.
METHODS: Data on prostate cancer mortality, food consumption, tobacco use, socioeconomic factors, reproductive factors, and health indicators were obtained from United Nations sources. Linear regression models were fit to these data. The influence of each variable fit in the regression models was assessed by multiplying the regression coefficient b by the 75th (X75) and 25th (X25) percentile values of the variable. The difference, bX75 - bX25, is the estimated effect of the variable across its interquartile range on mortality rates measured as deaths per 100000 males aged 45-74 years. Reported P values are two-sided.
RESULTS: Prostate cancer mortality was inversely associated with estimated consumption of cereals (bX75 - bX25 = -7.31 deaths; P = .001), nuts and oilseeds (bX75 - bX25 = -1.72 deaths; P = .003), and fish (bX75 - bX25 = -1.47 deaths; P = .001). In the 42 countries for which we had appropriate data, soy products were found to be significantly protective (P = .0001), with an effect size per kilocalorie at least four times as large as that of any other dietary factor. Besides variables related to diet, we observed an association between prostate cancer mortality rates and a composite of other health-related, sanitation, and economic variables (P = .003).
CONCLUSIONS: The specific food-related results from this study are consistent with previous information and support the current dietary guidelines and hypothesis that grains, cereals, and nuts are protective against prostate cancer. The findings also provide a rationale for future study of soy products in prostate cancer prevention trials