This dissertation’s three studies investigated the short and long-term relationships of bone-related nutrient intakes with bone mineral density (BMD) in postmenopausal women. This dissertation compared the equivalency of dietary intakes assessed by eight days of diet records (DR) and the Arizona Food Frequency Questionnaire (AFFQ) at one year. It also determined the association of one year (DR) and the average of four-year (AFFQ) dietary intakes with cross-sectional BMD. The dietary intake associations with BMD were further investigated by hormone therapy (HT). Participant’s BMD was measured at the lumbar spine (L2-L4), femur trochanter, femur neck, Ward's triangle and total body using dual energy X-ray absorptiometry. Separate multiple linear regression analysis (p≤0.05), controlled for various covariates, were used to examine the associations between dietary intakes and regional and total body BMD. In study number one (n=266), significant correlations (r=0.30-0.70, p≤0.05) between dietary assessment methods were found with all dietary intake variables. Iron, magnesium, zinc, dietary calcium, phosphorous, potassium, total calcium, and fiber intakes were positively associated with BMD at three or more of the same bone sites regardless of the dietary assessment method at one year. In study number two (n=266), femur trochanter, lumbar spine, and total body BMD had mostly significant inverse associations with dietary polyunsaturated fatty acid (PUFA) intake at one year. In the HT group (n=136), inverse associations with dietary PUFA intake were seen in the spine and total body BMD. In study number three (n=130), average dietary intake of selected bone-related nutrients, were significantly inversely associated with lumbar spine BMD and total body BMD at year four. In the HT group (n=92), inverse associations with dietary PUFA intake were seen in the spine and total body BMD. The DR and AFFQ are acceptable dietary tools used to determine the associations of particular nutrients and BMD sites in healthy postmenopausal women at one year. At one and four year, dietary PUFA intakes had mostly inverse associations with lumbar spine and total body BMD. When categorized by HT use the associations remained significant only in the HT groups, suggesting that HT may influence dietary intake associations with BMD.

This dissertation explores geographic and diachronic variation in Great Plains and Rocky Mountain Paleoindian (12,500-7000 14C years before present) forager exploitation of animal resources in order to explore how use of different habitats influenced land-use and subsistence strategies. To accomplish this goal, this study documented the full range of variability in the Paleoindian record using a combination of published data and new data. These patterns were then compared to explicit predictions derived from behavioral ecology and animal ethology and biology studies. The results, presented in this dissertation, allow the testing of several, often contradictory, important subsistence-settlement hypotheses in current Paleoindian research, specifically the ongoing debate about Paleoindian diet breadth and human causes of megafaunal extinction. Overall, there appears to be a covariance between environmental zone and forager land use. Paleoindian foragers structured their land use according to the presence and nature of a number of important resources within major environmental zones. Specifically, this study finds sites in grassland settings with low diversity of resources have lower artifact densities and are often dominated by exotic lithic raw materials. In these same areas prehistoric groups made almost exclusive use of large fauna. Sites in foothill/mountain or alluvial valley settings with ecologically high density and high diversity have higher proportions of short-term camps than do other areas and those camps have higher artifact density than do other types of sites. These sites exhibit a mixed use of small- and medium-sized game. Overall this study shows Paleoindian hunters had only modest impact on prey species.

Obesity-related diseases account for the majority of morbidity and mortality in U.S. adults. An estimated 4 million women in the United States deliver an infant annually, of which approximately 34% are overweight/obese prior to pregnancy. More than 30% of these women gain weight that exceeds the IOM’s recommendations; increasing their risk of postpartum weight retention and possibly increasing their risk of greater weight gain and retention over time. This research sought to test the efficacy of a traditional MED diet for 4-months on weight loss/control and biomarkers of inflammation in breastfeeding women compared to women randomized to the USDA’s MyPyramid diet for Pregnancy and Breastfeeding (control diet). At baseline, the women (N=129) were 29.7±4.6 years, overweight (BMI: 27.2±4.9 kg/m2), and primarily non-Hispanic white (75.2%). The majority of women were exclusively breastfeeding (73.6%) and a mean 17.5 weeks postpartum. Adherence to the MED diet was evaluated via calculation of the MED diet score from validated FFQs administered pre- and post- the diet intervention. Anthropometric measurements (body weight, body fat, and waist and hip circumference) and biosamples (blood, urine, and breast milk) were collected at baseline and 4-months (diet completion). Biomarkers of inflammation (IL-6 and TNF-α) were assessed via standard ELISA kits. The MED diet score was increased by 0.68±2.74 and 0.27±1.57 for the MED and control group, respectively. Increases in fish and dairy intake and a decrease in meat/poultry intake were significantly different between diet groups (P<0.05). Participants in both diet groups demonstrated significant (P=0.002) reductions in all anthropometric measurements; no significant between group differences were shown. A significant decrease in TNF-α, but not IL-6, was demonstrated in both diet groups. There were no significant between group differences. Both the MED diet and the USDA’s MyPyramid diet were effective in reducing anthropometric measurements and inflammation in postpartum breastfeeding women.

No description available.

OBJECTIVE: The main aim of this thesis was to investigate the role of nutrition during "early" HIV-infection in African women. METHODS: Data reported in this investigation formed part of two cross-sectional studies, the THUSA and Mangaung studies. The Mangaung study investigated women and, therefore, the sub-sample of the THUSA study was chosen accordingly. The data of the two studies were kept and analysed separately. The investigation consisted of 1040 women from the THUSA study, aged between 15 and 90 years of which 120 (11.5%) were HIV infected. The Mangaung study comprised of 488 women aged between 25 and 44 years of which 248 (51%) women were infected. Demographic data, anthropometric measurements, health outcome variables and habitual nutrient intakes by a quantified food frequency questionnaire were used. The SPSS statistical package (version 14.0; SPSS Inc., Chicago, Illinois, 2005) was used to analyse data. Descriptive statistics were done expressing variables as means, medians, standard deviations (SD), standard errors (SE) and confidence intervals (CI). An analysis of variance (ANOVA) was done to test for significance between the HIV-infected and non-infected groups in both studies. Partial correlations were done in the infected and non-infected groups to determine associations between dietary / nutrient intake, anthropometry and the biological health variables. In the THUSA study we controlled for age, education level, degree of urbanization and alcohol intake and in the Mangaung study for age, education level and alcohol intake. Nutrient intakes of both infected and non-infected women above and below median values as well as in the first and fourth quartile of total cholesterol (TC) and albumin distribution were compared to assess the role of nutrients in the observed decreases in TC and albumin of HIV-infected women. RESULTS AND DISCUSSION: The dietary intakes of the HIV-infected women in both the studies did not differ significantly from the non-infected women. Total serum cholesterol, albumin, fibrinogen and blood pressure were significantly lower in the HIV-infected women in both the THUSA and Mangaung studies. The non-infected THUSA women with lower serum cholesterol levels (than the median) had significantly lower intakes of percentage energy from fat (25.2 versus 26.4%, p ≤0.027), percentage energy from total protein (11.6 versus 12.1%, p≤0.000), animal protein (25.6 versus 27.7g, p≤0.005), and significantly higher intakes of plant protein (32.2 versus 29.4g, p≤0.002) and fibre (16.9 versus 15.89 p≤0.029). There were no significant differences observed in the nutrient intakes in the infected women with serum cholesterol levels above and below the median. In the Mangaung study no significant nutrient intake differences were observed in both of the HIV-infected and non-infected women with lower and higher than the median TC levels. In the THUSA study, higher intakes of fat (percentage energy) were close to significant (27.3 versus 24.5%, p≤0.053) in the infected women with higher (than the median) albumin levels. In the non-infected group with higher albumin levels, significant differences were observed in percentage energy from fat (26.6 versus 24.9%; p≤0.001) protein (12.2 versus 11.6%; p≤0.001) and carbohydrate (62.8 versus 65.2%; p≤0.000). Higher intakes of saturated fat (SATFAT) (17.7 versus 16.1g, p≤0.008), monounsaturated fats (MUFAT) (19.3 versus 17.4g, p≤0.004) as well as higher intakes of animal protein (28.5 versus 24.4g, p≤0.000) were observed in the group with higher than the median levels of serum albumin. In the Mangaung study the HIV-infected women (with higher than the median serum albumin levels), had significantly higher intakes of energy (13 275 versus 11 622 kJ, p≤0.022), polyunsaturated fatty acids (32.3 versus 17.3g, p≤0.036), dietary cholesterol (412.9 versus 344.5mg, p≤0.043) and plant protein (42.3 versus 35.3g, p≤0.008). No differences were observed in the non-infected women. The further analyses, comparing the dietary intakes in both studies of infected and non-infected women with TC and albumin levels in the first and fourth quartiles, showed that in the THUSA study, non-infected women with lower TC levels had significantly lower intakes of protein (% of total energy), total fat (% of total energy) and vitamin B12 and significantly higher intakes of total energy (TE), plant protein, total carbohydrate, % TE from carbohydrate, dietary fibre, added sugar and thiamine. In the infected women saturated fatty acids (SATFAT), calcium and the fat ratio (polyunsaturated/saturated ratio) differed significantly between women with TC levels in the first and the fourth quartile. A significant higher intake of riboflavin was seen in the non-infected women from Mangaung with TC levels in the fourth quartile, while significant higher intakes of energy, total protein, animal protein, total fat, SATFAT, MUFAT, total carbohydrate, phosphorus, chromium and iodine was seen in the infected women with TC levels in the fourth quartile. These results suggest that a more "westernized" diet with higher intakes of energy, and animal derived foods (SATFAT and calcium) could have protected against the detrimental decreases in TC observed in HIV infection. Significant differences were observed in the intakes in the non-infected THUSA women who had serum albumin in the first and fourth quartiles. lntakes in percentage energy from protein and fat, animal protein, total fat, SATFAT, MUFAT, calcium, zinc, vitamin C and fat ratio, were significantly lower in the women with albumin levels in the first quartile. Significantly higher carbohydrate intakes were observed in the women who had serum albumin levels in the first quartile. In the Mangaung study, significant differences were seen in the intakes between infected women who had serum albumin levels in the first and fourth quartiles. lntakes of total energy, protein, fat, MUFAT, SATFAT, carbohydrate, magnesium, zinc, chromium, biotin, pantothenic acid and iodine were significantly lower in the infected women with serum albumin levels in the first quartile. In the non-infected women significantly lower intakes of calcium were observed in the group who had serum albumin levels in the first quartile compared to those who had serum albumin levels in the fourth quartile. These results also suggest that a more "westernized” diet was associated with higher albumin levels in HIV-infected women. CONCLUSION: It is well known that nutrition has an integral part to play in the care of people living with HIV/AIDS (PLWHA). Maintaining proper nutrition, weight and immune function is thought to delay disease progression, prolong the asymptomatic phase and improve survival. These analyses suggest that the "prudent" diet generally regarded as an optimal diet for prevention of non-communicable diseases, may not be the optimal diet for PLWHA. The overall analyses therefore suggest that a more "westernized" diet, higher in fat and protein could be more beneficial to asymptomatic HIV-infected women compared to that of a more "prudent" diet. As these studies were not primarily designed to investigate HIV and nutrition, the role of a higher energy, fat and animal protein intake ("western" diet) in asymptomatic HIV warrants urgent investigation. / Thesis (Ph.D. (Nutrition))--North-West University, Potchefstroom Campus, 2007.

This investigation studies the effects of diets containing varying amounts of linoleic acid (a polyunsaturated fatty acid) and stearic acid (a saturated fatty acid) on tumorigenesis, weight and longevity in strain A/ST mice. Linoleic acid [ 18 carbons and 2 double bonds (18:2)] was chosen to represent a fatty acid known to enhance tumorigenesis and obesity in certain strains of mice. Stearic acid [ 18 carbons and no double bonds (18:0)] represents a saturated fatty acid known to increase the latency period for mammary tumor development and to decrease the rate of tumor growth. This study was conducted to determine whether the effects of fatty acids observed in younger mice on time to tumor, survival and body weights were also found in aging animals. Further, by varying the amount of linoleic acid in the diet, this study examined whether the tumor enhancing effects of increasing amounts of linoleic acid could be overcome by the incorporation of dietary stearic acid. All diets had equal percentages, by weight, of protein, salt, sucrose, mineral salt, and vitamin levels and an equal number of calories per gram of food. The SF diet was rich in linoleic acid. The SA-1 diet contained enough linoleic acid to prevent essential fatty acid deficiency, and the SA-4 diet contained the maximal amount of linoleic acid for tumor enhancement. Total body weight and tumor production in the three dietary groups show a relationship between an increase in body weight and tumor production as the amount of dietary linoleic acid increases. There also is an inverse relationship between animal survival and body weight as the amount of dietary linoleic acid increases. Survival thus appears to be dependent on tumor production in the three dietary groups, where there appears to be an inverse relationship between survival and time to tumor as the amount of dietary linoleic acid increases at each timepoint. These results suggest that the inclusion of stearic acid in the diet can, in part, overcome this enhancing effect of linoleic acid, even at the optimal tumor producing level of linoleic acid. The results of this study indicate that that effects of linoleic and stearic acid in aging mice are similar to those in younger animals. / Department of Biology

Maternal obesity is associated with adverse effects for mothers and offspring. The primary aim of this thesis was to assess food intake and physical activity (PA) using validated self-administered questionnaires, and whether these were associated with gestational weight gain (GWG) and birthweight (BWT), in severely obese (body mass index, BMI≥40kg/m2) compared with lean pregnant women (BMI 20-25kg/m2). The secondary aims were to validate self-reports against food diary (FD) and accelerometry; to assess the prevalence of under or over-reporting of energy intake; and to carry out a pilot study to assess total energy expenditure, as well as self-reporting accuracy, by using doubly-labelled water (DLW) technique, in subgroups of participants. Pregnant women were recruited from an ongoing study of severe obesity in pregnancy at the Royal Infirmary of Edinburgh, UK. Assessments were done in early (12-20 weeks) and late (28-32 weeks) pregnancy. A subgroup of women also completed questionnaires on appetite, general nutrition knowledge, and eating behaviours. All results were adjusted for age, parity, ethnic origin and deprivation category score. Self-reported total energy intake was not significantly different between obese and lean during early (median 2,444 vs 2,312 kcal/day) and late (2,173 vs 2,354 kcal/day) pregnancy. However when validated with FD, the relative validity of the food frequency questionnaire was lower in obese compared to lean. Under-reporting of total energy intake was higher in obese compared to lean (49% vs 15%, P<0.01) through comparison of selfreported energy intake with estimated total energy expenditure, and this was supported by the DLW pilot study results. The DLW also showed possible over-reporting of PA by the obese group. Obese women reported significantly lower appetite than lean throughout pregnancy (P<0.01). They also had lower scores in general nutrition knowledge, but these were no longer significant after controlling for confounders. Obese women had significantly higher scores of restrained and emotional eating behaviours than, and similar scores of external eating behaviours to, lean. Appetite, nutrition knowledge, restraint and emotional eating behaviours scores were not associated with food intake in either obese or lean. On the other hand, increased intakes of total calories and fats were influenced by increasing score of external eating behaviour in both groups. Obese women reported doing similar amounts of total PA but significantly less of vigorous and sports and exercise activities than lean (P<0.05). Accelerometry showed obese women had lower average activity counts/day, although they did have significantly greater energy expenditure in light-intensity activity than lean (P<0.01). Obese women had less GWG than lean (Mean ± SD, 5.3± 52 vs 10.8±3.7kg, P<0.001). Increased GWG was associated with increased self-reported total energy intake in lean, but this was not seen in obese. GWG was not associated with PA in either group. BWT was not significantly different between obese and lean (3,547±549g vs 3,567±516g). In lean, increased BWT was associated with increased energy intake and total PA. BWT in obese was not associated with diet but with increased with PA in early pregnancy. In conclusion, self-reported methods were less reliable in assessment of diet and PA in severely obese compared to lean pregnant women. These exploratory studies found that obese women did not appear to have the same factors as lean women affecting GWG and BWT, though this may be complicated by the poor reliability of self-reports. Therefore, quantitative assessments such as measurement of serum micronutrient levels (to evaluate nutritional status), and accelerometry (to assess physical activity) may be necessary in this poorly understood population.

Background/Objective: Several studies have shown that a low carbohydrate diet (LCHOD) can improve glycaemic control in type 2 diabetes (T2DM). The objective of the current study was to compare two ways of administration of a LCHOD: self-prepared meals versus ready-made meals, and their effects on weight loss, glycaemic control, body composition, cardiovascular risk and resting metabolic rate over 12 months. Research design and methods: Forty-one volunteers with the mean body mass index of 38.8 kg/m2 and poorly controlled T2DM (glycosylated haemoglobin, HbA1c > 7.5%) were randomized to either protein sparing modified fast (< 40g of carbohydrate daily, self-cooked; PSMF) or Go Lower (readymade meals; GL) diet. Both groups received multivitamin supplementation and attended monthly visits. The main outcome was weight loss and its composition. Results: Fourteen (34 %) participants completed 12 months of the intervention. There were no differences in the weight or any other changes between the diet groups at 12 months. Overall, body mass and fat mass decreased (-5.5 ± 7.3 kg, P < 0.001 and -5.1 ± 6.7 kg, P < 0.001 respectively) but fat free mass did not change. There was an overall reduction in HbA1c (-0.4 ± 1.1 %, P < 0.001), increase in HDL-cholesterol (+0.07 ± 0.18 mmol/L, P < 0.001) and decrease in triacylglycerol (-0.6 ± 2.4 mmol/L, P = 0.014). Resting metabolic rate significantly decreased (-137 ± 265 kcal/d, P < 0.001). Conclusion: LCHOD, independently of the approach taken, led to weight loss and improvements in glycaemic control in obese volunteers with poorly controlled T2DM. The results confirm that lifestyle modification using LCHOD is effective for improving T2DM and suggest that the type of approach to the diet can be matched to an individual’s preferences.

A new, Internet-based Food Recall Checklist (FoRC) was developed to assess students diet; a checklist of 121 foods consumed on the previous day which was completed on multiple days.  FoRC was validated against a non-weighted diet record in two studies (n=94).  Novel feedback messages for students were created and software was developed to link these messages to results from individual dietary assessment in FoRC.  An intervention trial was planned to measure students’ diet and to deliver tailored nutrition messages via the Internet, to assess whether tailored dietary feedback could help to promote healthy diet change. General dietary intake of the sample was analysed using one-day diet records from 459 undergraduate students.  The dietary intake of the sample of students was found to be healthier than participants aged 19-24 years in the UK-wide National Diet and Nutrition Survey.  However, there was evidence of poor dietary habits; Non-Milk Extrinsic Sugars (NMES) intake exceeded the maximum daily guideline intake and fruit and vegetable and Non-Starch Polysaccharide intakes did not meet recommendations. There was also evidence of excessive consumption of unhealthy foods, such as alcohol, crisps and confectionary. Change in dietary intake was assessed in an <i>intervention </i>group and <i>control </i>group.  The <i>intervention </i>group received feedback after baseline, three and six month completion of four days of FoRC.  The retention rate was very low, but in participants who completed the protocol NMES intake significantly decreased in the <i>intervention </i>group at six  months compared to the <i>control </i>group (p=0.017). It was concluded that monitoring diet in students may still be an important public health objective; students may be relatively healthy, but may still benefit from nutrition surveillance and advice.

With the increased marketing and popularity of a range of dairy products in recent years, research has become widespread concerning the influence of dairy on human health. It is also becoming evident that an individual’s genetic make-up contributes to shaping their health responses to dietary intakes. This research was primarily designed to investigate the impact of genetic variability on responsiveness of cholesterol metabolism, a classic biomarker of cardiovascular health, to the recommended level of dairy consumption in Canada. A secondary objective was to assess the influence of dairy intake on systemic inflammation as an emerging risk factor for cardiovascular disease. In a multicentre, randomized, free-living crossover design, 124 healthy individuals consumed 3 servings/day of conventional low-fat and regular milk, yogurt, and cheese (DAIRY diet) or dairy-free control products (CONTROL diet), each for 28 days as part of a prudent background dietary protocol. At the end of the study, DAIRY was associated with increased plasma concentrations of two established fatty acid biomarkers of dairy fat, pentadecanoic acid (C15:0) and heptadecanoic acid (C17:0), as well as with small increases in serum total cholesterol (TC) and LDL-cholesterol (LDL-C) concentrations. Inter-individual variability in the cholesterol transport gene ABCG5, bile acid synthesis gene CYP7A1, and cholesterol synthesis gene DHCR7 contributed to shaping the degree of TC and LDL-C responsiveness to DAIRY; with higher cholesterol concentrations observed among ABCG5 rs6720173-G/G homozygotes, CYP7A1 rs3808607-G allele carriers, and DHCR7 rs760241-A allele carriers, relative to the C allele, T/T, and G/G carriers of these genes, respectively. Also, after DAIRY, the major allele T homozygosity of CYP7A1 rs3808607 and the minor allele A of DHCR7 rs760241 were associated with reduced plasma [3,4]13C cholesterol enrichment and deuterium incorporation, respectively, suggesting reduced cholesterol absorption and synthesis rates. DAIRY intake did not influence the inflammatory status. Overall, this research has provided evidence of a potential impact of the genomic architecture on responsiveness of cholesterol metabolism to dairy consumption. The novel findings are expected to advance knowledge of the inherited basis by which health biomarkers may be modified in response to whole foods, hence launching an important step towards an era of personalized nutrition. / February 2016