Biomedical subjects

Susan J Whiting

Publications and source records attributed to Susan J Whiting.

28 records · Page 2Linked to original sources

PubMed2004

Factors that affect bone mineral accrual in the adolescent growth spurt.

The development of bone mass during the growing years is an important determinant for risk of osteoporosis in later life. Adequate dietary intake during the growth period may be critical in reaching bone growth potential. The Saskatchewan Bone Mineral Accrual Study (BMAS) is a longitudinal study of bone growth in Caucasian children. We have calculated the times of maximal peak bone mineral content (BMC) velocity to be 14.0 +/- 1.0 y in boys and 12.5 +/- 0.9 y in girls; bone growth is maximal approximately 6 mo after peak height velocity. In the 2 y of peak skeletal growth, adolescents accumulate over 25% of adult bone. BMAS data may provide biological data on calcium requirements through application of calcium accrual values to factorial calculations of requirement. As well, our data are beginning to reveal how dietary patterns may influence attainment of bone mass during the adolescent growth spurt. Replacing milk intake by soft drinks appears to be detrimental to bone gain by girls, but not boys. Fruit and vegetable intake, providing alkalinity to bones and/or acting as a marker of a healthy diet, appears to influence BMC in adolescent girls, but not boys. The reason why these dietary factors appear to be more influential in girls than in boys may be that BMAS girls are consuming less than their requirement for calcium, while boys are above their threshold. Specific dietary and nutrient recommendations for adolescents are needed in order to ensure optimal bone growth and consolidation during this important life stage.

Adolescent↗

PubMed2004

A questionnaire to examine food service satisfaction of elderly residents in long-term care facilities.

The purpose of this study was to develop a survey tool for assessing the satisfaction of elderly long-term care (LTC) residents with the meals and food services they receive, as well as to assess quality of life issues related to eating. Food service delivery should be provided in an environment that fosters autonomy, interpersonal relations, and security. The questionnaire was administered as face-to-face interviews with 205 residents (> or = 65 years of age) of 13 LTC facilities in Saskatoon, Saskatchewan, Canada (participation rate = 67%). Residents expressed some concern with food variety, quality, taste, and appearance, and with the posting of menus. Quality of life issues were mostly positive; however, residents were less satisfied with areas related to their autonomy such as food choice and snack availability.

Aged↗

PubMed2004

Early milk intake, later bone health: results from using the milk history questionnaire.

Milk intake is considered an important determinant of peak bone mass; consequently, its intake early in life may decrease risk of osteoporotic fractures later. Using the milk history questionnaire, many investigators have conducted retrospective cross-sectional studies and have determined a positive effect of milk intake in childhood and adolescence on bone mineral density in adult white women. By contrast, a recent study indicates that early milk intake has no beneficial effect on bone mineral density in black women. The milk history questionnaire can assist in determining diet-bone relationships in various groups.

Adolescent↗

PubMed2003

Increased stool frequency occurs when finely processed pea hull fiber is added to usual foods consumed by elderly residents in long-term care.

Dietary fiber fortification of food offers a preventative strategy that is a less invasive alternative to laxatives and enemas in the management of constipation in elderly individuals. To determine if a moderate increase in fiber provided in foods would increase bowel movement frequency among elderly institutionalized residents, data were collected on the same elderly residents (n=114) before and during a 6-week intervention. The intervention consisted of adding finely processed pea hull fiber (1-3 g/serving) to 3 to 4 foods each day. Laxative and enema use was monitored. Mean number of bowel movements/month increased from 18.7+/-9.4 to 20.1+/-9.6 (n=114, P=.034), and in 17 residents with low baseline frequency, the increase was highly significant (8.8+/-1.0 to 12.6+/-3.8 bowel movements/month, P=.001). With treatment, prune-based laxative administration decreased (P<.001). Thus, addition of a moderate amount of finely processed fiber to foods results in increased bowel frequency in institutionalized elderly individuals.

Aged↗

PubMed2003

Effect of folic acid supplementation on plasma zinc concentrations of young women.

OBJECTIVE: Women of reproductive age are advised to consume supplements or fortified foods containing at least 400 microg/d folic acid for the prevention of neural tubes defects. Concerns exist about the adverse effects of folic acid on zinc status. METHODS: Seventy-eight women (18 to 49 y) were assigned for 12-wk to receive either a placebo or a 400 microg/d folic acid supplement. RESULTS: At 12-wk mean (95% CI) red cell folate increased by 431 (350-511) nmol/L in the supplemented group relative to placebo (P < 0.001) but there was no change in plasma zinc in either group (P = 0.213). CONCLUSIONS: Folic acid supplementation does not reduce plasma zinc concentrations in women of childbearing age.

Adolescent↗

PubMed2003

Prevalence of vitamin D insufficiency in Canada and the United States: importance to health status and efficacy of current food fortification and dietary supplement use.

Several recent studies have identified a surprisingly high prevalence of vitamin D insufficiency in otherwise healthy adults living in Canada and the United States. Most striking are the effects of latitude, season, and race. Also noteworthy is that dietary vitamin D is not reaching the population in greatest need, nor is it very protective against insufficiency. Fluid milk, as the predominant vehicle for vitamin D fortification, is apparently not very effective in staving off vitamin D insufficiency in adults in all populations at all times of the year.

Black People↗

PubMed2002

Dietary protein, phosphorus and potassium are beneficial to bone mineral density in adult men consuming adequate dietary calcium.

OBJECTIVE: The purpose of this study was to determine relationships of calcium (Ca), protein (Pr), phosphorus (P) and potassium (K) to measures of bone mineral density in adult men. METHODS: Cross-sectional analysis of 57 men ages 39 to 42 years who were participants in an ongoing study. Dietary assessment was conducted using the Block food frequency questionnaire (FFQ). BMD of total body (TB), hip and lumbar spine (LS) were measured with dual X-ray absorptiometry (DXA). RESULTS: Ca, Pr, P and K, as well as lean body mass (LBM), showed significant correlation with BMD at the total body, hip and lumbar spine. Stepwise forward regression selection method identified LBM, height and fat mass as significant predictors of TB-BMD, LBM and height as significant predictors of hip BMD, and LBM as a significant predictor of LS-BMD. As the nutrients tested correlated significantly with each other, only one nutrient was entered into the regression model at a time to accommodate the potential for multicollinearity. In regression analysis, adjusted for site-specific anthropometric variables and energy intake, K, Pr and P intake accounted for significant (p < 0.05) prediction of TB-BMD and LS-BMD values by 7% to 13%. No bone-related nutrient added significantly to the prediction of hip BMD. Ca intake was not significantly associated with BMD at any site in the adjusted models. CONCLUSIONS: Our analysis provides support that a moderate protein (1.2 g/kg) diet, plentiful in potassium (>100 mmol/day) and phosphorus (1741 +/- 535 mg) is beneficial for maintaining bone mineral density in adult men when Ca intake was adequate (1200 +/- 515 mg).

Absorptiometry, Photon↗

PubMed2002

Elderly women need dietary protein to maintain bone mass.

Excess dietary protein is considered a risk factor for osteoporosis owing to the potential for renal acid load. Researchers who conducted a recent prospective study of older adults reported that animal protein had a protective role for bone, especially in elderly women, whereas plant protein was negatively associated with bone mineral density. An interaction between protein and calcium suggested protein alone was not the important factor. Other studies confirm the beneficial effect of increasing dietary protein intake in older women to reduce bone mineral density loss and risk of fracture, suggesting that emphasis should be placed on promoting adequate protein intake in elderly women.

Aged↗

PubMed2002

Obesity is not protective for bones in childhood and adolescence.

Although body weight is considered to positively affect bones of children and adults, recent studies suggest that overweight and obesity in childhood and adolescence reduce bone mineral content below what would be predicted based on weight and are associated with an increase in incidence of childhood fractures.

Adolescent↗

PubMedDate not supplied

D-lactate production and excretion in diarrheic calves.

The origin of D-lactate, the most important acid contributing to metabolic acidosis in the diarrheic calf, is unknown. We hypothesized that because D-lactate is produced only by microbes, gastrointestinal fermentation is the source. The objective of this study was to determine whether D-lactate production occurs in the rumen, colon, or both, and to measure D- and L-lactate concentrations in urine. Fecal, rumen, blood, and urine samples were obtained from 16 diarrheic and 11 healthy calves. Serum electrolyte concentrations were measured in both groups, and blood gas analyses were performed for diarrheic calves. All samples were analyzed for D- and L-lactate by high performance liquid chromatography (HPLC). Diarrheic calves were generally hyperkalemic with high serum anion gap, depressed serum bicarbonate, and low blood pH. L-lactate was markedly higher in rumen contents (22.7 mmol/ L [median]) and feces (8.6 mmol/L) of diarrheic calves than healthy calves (0.5 mmol/L and 5.1 mmol/L, respectively), but not different in serum or urine. Rumen, fecal, serum, and urine D-lactate concentrations were all significantly higher (P < .05) in diarrheic calves (17.0, 25.4, 13.9, and 19.2 mmol/L, respectively) than in healthy calves (0.5, 9.1, 1.4, and 0.5 mmol/L, respectively). Higher D-lactate concentrations in the rumen and feces of diarrheic calves suggests these sites as the source of D-lactate in blood and urine.

Acetic Acid↗