Soy formula complicates management of congenital hypothyroidism.
(1/63)
AIMS: To test the hypothesis that feeding soy formula to infants with congenital hypothyroidism (CH) leads to prolonged increase of thyroid stimulating hormone (TSH). METHODS: The study was a review of 78 patients seen during their first year of life between 1990 and 1998. Data regarding clinical diagnosis, date of treatment initiation, TSH, levothyroxine dose, weight, length, and diet information from each visit were collected from the charts. RESULTS: There were eight patients in the soy diet group and 70 in the non-soy diet group. There was no significant difference between the two groups in the starting dose of levothyroxine or the change in this dose over one year. There was a significant difference between the two groups in the following areas: time to TSH normalisation, first TSH on treatment, percentage with increased TSH at 4 months of age, percentage with increased TSH throughout the first year of life, and in the overall trend of TSH at each visit. CONCLUSIONS: Infants fed soy formula had prolonged increase of TSH when compared to infants fed non-soy formula. These infants need close monitoring of free thyroxine and TSH measurements, and they may need increased levothyroxine doses to achieve normal thyroid function tests. (+info)
Soy intervention in adolescent girls: design and implementation.
(2/63)
The purpose of this study was to explore the feasibility of implementing a soy intervention in female adolescents. Twenty girls, ages 8 to 14, were recruited to consume 1 daily serving of soymilk or soy nuts. They also provided 9 weekly urine samples over a 2-month period. Information about the study foods and procedures was collected through post-study questionnaires. Adherence to the intervention was successful using strategies that addressed both girls' and mothers' needs. The use of conveniently packaged soy foods, activities to maintain motivation, and frequent contact maintained participation. Future studies should also consider the maturity and sense of responsibility of participants to achieve compliance. (+info)
Reduction of non-digestible oligosaccharides in soymilk: application of engineered lactic acid bacteria that produce alpha-galactosidase.
(3/63)
Human consumption of soy-derived products has been limited by the presence of non-digestible oligosaccharides (NDO), such as the alpha-galactooligosaccharides raffinose and stachyose. Most mammals, including man, lack pancreatic alpha-galactosidase (alpha-Gal), which is necessary for the hydrolysis of these sugars. However, such NDO can be fermented by gas-producing microorganisms present in the cecum and large intestine, which in turn can induce flatulence and other gastrointestinal disorders in sensitive individuals. The use of microorganisms expressing alpha-Gal is a promising solution to the elimination of NDO before they reach the large intestine. In the present study, lactic acid bacteria engineered to degrade NDO have been constructed and are being used as a tool to evaluate this solution. The alpha-Gal structural genes from Lactobacillus plantarum ATCC8014 (previously characterized in our laboratory) and from guar have been cloned and expressed in Lactococcus lactis. The gene products were directed to different bacterial compartments to optimize their possible applications. The alpha-Gal-producing strains are being evaluated for their efficiency in degrading raffinose and stachyose: i) in soymilk fermentation when used as starters and ii) in situ in the upper gastrointestinal tract when administered to animals orally, as probiotic preparations. The expected outcomes and possible complications of this project are discussed. (+info)
Pharmacokinetics of isoflavones, daidzein and genistein, after ingestion of soy beverage compared with soy extract capsules in postmenopausal Thai women.
(4/63)
BACKGROUND: Isoflavones from soybeans may provide some beneficial impacts on postmenopausal health. The purpose of this study was to compare the pharmacokinetics and bioavailability of plasma isoflavones (daidzein and genistein) after a single dose of orally administered soy beverage and soy extract capsules in postmenopausal Thai women. METHODS: We conducted a randomized two-phase crossover pharmacokinetic study in 12 postmenopausal Thai women. In the first phase, each subject randomly received either 2 soy extract capsules (containing daidzin : genistin = 7.79 : 22.57 mg), or soy beverage prepared from 15 g of soy flour (containing daidzin : genistin = 9.27 : 10.51 mg). In the second phase, the subjects received an alternative preparation in the same manner after a washout period of at least 1 week. Blood samples were collected immediately before and at 0.5, 1, 2, 4, 6, 8, 10, 12, 24 and 32 h after administration of the soy preparation in each phase. Plasma daidzein and genistein concentrations were determined by using high performance liquid chromatography (HPLC). The pharmacokinetic parameters of daidzein and genistein, i.e. maximal plasma concentration (Cmax), time to maximal plasma concentration (Tmax), area under the plasma concentration-time curve (AUC) and half-life (t1/2), were estimated using the TopFit version 2.0 software with noncompartmental model analysis. RESULTS: There were no significant differences in the mean values of Cmax/dose, AUC0-32/dose, AUC0- proportional, variant/dose, Tmax, and t1/2 of genistein between both preparations. For pharmacokinetic parameters of daidzein, the mean values of Cmax/dose, Tmax, and t1/2 did not significantly differ between both preparations. Nonetheless, the mean AUC0-32/dose and AUC0- proportional, variant/dose after administration of soy extract capsules were slightly (but significantly, p < 0.05) higher than those of soy beverage. CONCLUSION: The bioavailability of daidzein, which was adjusted for the administered dose (AUC/dose), following a single oral administration of soy beverage was slightly (but significantly) less than that of soy extract capsules, whereas, the bioavailability adjusted for administered dose of genistein from both soy preparations were comparable. The other pharmacokinetic parameters of daidzein and genistein, including Cmax adjusted for the dose, Tmax and t1/2, were not different between both soy preparations. (+info)
Effect of fermented soy milk on the intestinal bacterial ecosystem.
(5/63)
AIM: To investigate the effect of fermented soy milk on human ecosystem in the intestinal tract by way of examining the population of different microorganisms isolated from fecal samples. METHODS: A crossover experimental design was applied. Twenty-eight healthy adults completed this experiment. Each subject consumed 250 mL, twice a day between meals, of either fermented soy milk or regular soy milk first for 2 wk, then switched to the other drink after 2 wk. Fecal samples were collected from all subjects every week starting from the second week to the end of the experiment. The microorganisms analyzed were Bifidobacterium spp., Lactobacillus spp., Clostridium perfringens, coliform organisms, and total anaerobic organisms. RESULTS: In the period of fermented soy milk consumption, the populations of Bifidobacterium spp. and Lactobacillus spp. increased (P<0.05) as well as the ratios of Bifidobacterium spp. and Lactobacillus spp. to Clostridium perfringens (P<0.05). The population of coliform organisms decreased (P<0.05) when subjects were in the period of fermented soy milk consumption. CONCLUSION: Intake of fermented soy milk significantly improved the ecosystem of the intestinal tract in the body by increasing the amount of probiotics. (+info)
Dietary fat and an exogenous emulsifier increase the gastrointestinal absorption of a major soybean allergen, Gly m Bd 30K, in mice.
(6/63)
The mechanisms by which food allergens are absorbed and sensitized via the gastrointestinal tract have not been well characterized. In this study, the gastrointestinal absorption of a major soybean allergen, Gly m Bd 30K, in young and older mice, and the effects of dietary fat and exogenous emulsifier were investigated. In Expt. 1, Gly m Bd 30K [0, 500 or 2000 mg/kg body weight (BW)] was administered orally to 24-d-old mice, and blood was sampled at various time points over a 120-min period. Plasma Gly m Bd 30K was measured by sandwich ELISA and immunoblotting. Its concentration peaked at 30 min and was dose dependent. Intact Gly m Bd 30K and its 20-kDa fragments were identified in plasma after absorption. In Expt. 2, 24-d-old mice administered soy milk containing 1 mg Gly m Bd 30K showed a steady increase in plasma Gly m Bd 30K from 60 to 120 min that was significantly higher than that in 10-wk-old mice. In Expt. 3, when corn oil (5 or 30%) was coadministered with Gly m Bd 30K (2000 mg/kg BW) to 24-d-old mice, the plasma concentration increased significantly and generally reached a plateau after 30 min. The absorption after the coadministration of 30% corn oil and 3% sucrose fatty acid ester was higher than after the administration of 30% corn oil alone. Intact Gly m Bd 30K and its fragments that were < 20 kDa survived digestion and were absorbed into the blood. We propose that absorption was enhanced by fat carrier-mediated transport. (+info)
Calcium bioavailability of calcium carbonate fortified soymilk is equivalent to cow's milk in young women.
(7/63)
Calcium (Ca)-fortified soymilk has gained popularity in the United States. Tricalcium phosphate (TCP)-fortified soymilk was shown to have a lower Ca bioavailability than cow's milk in men. However, the most popular soymilk in the U.S. is fortified with Ca carbonate (CC) and has not been evaluated. Ca bioavailability from CC-fortified soymilk (CCSM) and TCP-fortified soymilk (TCPSM) was compared with cow's milk in young healthy women using the dual stable isotope technique. In a 3-way crossover design, 20 volunteers (23 +/- 2 y old) consumed 250 mg Ca in cow's milk, CCSM, or TCPSM along with 10 mg 44Ca after an overnight fast. Cow's milk was extrinsically labeled, whereas each fortified soymilk was intrinsically labeled with each chemical salt of 44Ca at the manufacturing facility. Another stable isotope, 43Ca, was injected i.v. 1 h after the complete consumption of cow's milk or soymilk. Fractional Ca absorption was determined from the ratios of 43Ca:42Ca and 44Ca:42Ca by inductively coupled plasma (ICP)-MS in the 24-h urine samples. A mixed linear model (SAS proc mixed) was used to compare the fractional Ca absorption among groups. Fractional Ca absorption in CCSM (0.211 +/- 0.057) did not differ from that of cow's milk (0.217 +/- 0.040), but both were higher (P < 0.05) than that of TCPSM (0.181 +/- 0.039). Our result suggests that calcium absorption is equivalent for CCSM and cow's milk at similar calcium loads. (+info)
Anaphylaxis in a milk-allergic child after ingestion of soy formula cross-contaminated with cow's milk protein.
(8/63)
In this report we describe a 9-month-old boy with severe persistent asthma and documented cow's milk allergy (presented with eczema and severe systemic reactions) who had an anaphylactic reaction to a soy formula contaminated with cow's milk protein. Quantitative enzyme-linked immunosorbent assay analysis revealed trace quantities of beta-lactoglobulin in the offending soy formula as well as the dry powder. The patient did not demonstrate clinical reactivity to soy protein (negative challenge, tolerated pure soy formula well). Cross-contamination of the offending soy formula was presumed to have occurred during food manufacturing. This case demonstrates that trace quantities of cow's milk protein can elicit severe systemic reactions in highly milk-allergic individuals. This infant ingested the equivalent of 0.4 mL of cow's milk from the soy formula as documented by an immunoassay for beta-lactoglobulin. This highlights the ease with which cross-contamination can occur during food processing and reinforces the need for better quality control. (+info)