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Item Using intermittent fasting and a ketogenic diet to improve nutritional and clinical outcomes in long-stay, hospitalised canine spinal patients : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Massey University, Manawatū, New Zealand(Massey University, 2021) Leung, Yuet-Ming BeccaA high prevalence of malnutrition occurs in human hospitals and has been associated with detrimental consequences. By comparison, very little is known in veterinary patients. Additionally, while underfeeding can lead to poorer outcomes, overfeeding hospital patients also causes negative effects, to the extent that purposeful caloric restriction has been touted as an ideal feeding regimen. Both caloric restriction and intermittent fasting (IF) have gained interest as therapeutic feeding regimens for several diseases, including neuronal injury. The aim of this thesis was to explore hospital nutrition and IF in dogs. Firstly, the prevalence of malnutrition and body composition changes were determined in long- stay hospitalised patients. Results showed that most patients lost weight during hospitalisation, mainly from muscle. Additionally, body and muscle condition scoring did not accurately measure changes in composition, particularly in lean dogs. So predictive equations of body composition using morphometry in lean dogs were created. While feasible, it was discovered that breed-specific equations are needed, limiting its use. Then, the metabolic and immunological effects of IF in healthy dogs were examined. Results showed that IF on a high-fat (HF) diet increased blood ketones and decreased leptin and ghrelin concentration. Also, a reduction in immunity occurred when the dogs were fasted after eating the low-fat diet, but not with the HF diet. Furthermore, ketone kinetics indicated that increasing the fasting duration from 24 to 48 hours caused highly variable responses amongst the dogs. Therefore, the beneficial effects of IF may be dependent on the individual. Finally, an IF regimen using a HF diet was applied in hospitalised dogs recovering from spinal injury. Results showed that the regimen was practical and reduced body weight loss. Also, higher fasted ketone concentrations were associated with shorter hospital durations in dogs that lost more weight. In summary, long-stay hospitalised dogs lose a substantial amount of muscle. Also, a HF diet fed intermittently can increase ketone concentrations and may benefit patients with spinal cord injury. However, more work is needed to better understand what influences the variation in ketogenesis and utilisation in healthy and diseased dogs, and test the effects in a larger study population.Item Determining the validity and reproducibility of the Healthy Heart Food Index : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Science in Nutrition and Dietetics at Massey University, Albany, New Zealand(Massey University, 2019) Guy, HarrietBackground: Diet quality is associated with cardiovascular disease (CVD) risk, and the New Zealand (NZ) Heart Foundation has produced dietary guidelines aimed at reducing CVD risk for adult New Zealanders. At present, there is no valid and reproducible diet quality index for older adults living in NZ, which focuses on CVD risk. Aim: To develop and determine the construct validity and reproducibility of the Healthy Heart Food index (HHFI) for measuring dietary patterns in older adults living in New Zealand. Method: The HHFI was developed based upon NZ Heart Foundation Guidelines. To assess HHFI reproducibility, 298 community dwelling participants aged 65-74 years completed the HHFl twice approximately four-weeks apart. To validate the index, 142 of these participants completed a four-day food record (4DFR). Construct validity was explored using Spearman's correlation coefficients and linear contrast analysis of selected nutrients from the 4DFR. Spearman's correlation coefficients, Wilcoxon ranked-signed tests, cross-classification, the weighted kappa statistic, and a Bland-Altman plot were used to assess HHFl reproducibility. Results: Mean HHFl total scores were 693i10.8 and 68.9i11.1 from the first and second HHFl administrations respectively. These scores were positively correlated (r= 0.662, P<0.001) and cross-classification showed 55.4% of participants were categorised into the same fertile and 6.3% were grossly misclassified. The weighted kappa statistic was K: 0.43, indicating moderate agreement between HHFI total scores. For construct validity, iron (r= 0.201), vitamin C (r= 0.174), and niacin (r= 0.205) (all P<0.05), and protein (r= 0.277), polyunsaturated fatty acids (r= 0.236), dietary fibre (r= 0.307), vitamin (r= 0.205), folate (r= (1268), potassium (r= 0.246), magnesium (r= 0.300), phosphorus (r= 0.281), zinc (r= 0.276), and selenium (r= 0.222) (all P<0.01), were positively correlated with the HHFI total score. Saturated fat and cholesterol were negatively correlated (r= -0.097 and -0.035 respectively) with the HHFI total score, however this was a non-significant association (P>0.05). Linear contrast analysis showed a significant positive association between polyunsaturated fat, monounsaturated fat, dietary fibre, potassium, folate (P<0.05), vitamin E (P<0.01), and magnesium (P<0.005) and HHFI total scores. Conclusion: Moderate adherence to the HHFI was shown in this population sample. Results indicate the HHFI demonstrated construct validity and good reproducibility for assessing CvD-related diet quality in older adults living in New Zealand. Further research is needed to examine the predictive validity of this index in relation to CVD risk.Item Influence of feed processing and enzyme supplementation on performance, nutrient utilisation and gut morphology of poultry fed barley-based diets : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Poultry Nutrition at Massey University, Palmerston North, Manawatu, New Zealand(Massey University, 2020) Perera, Wellawattage Nipuna UdayaniThe first experiment (Chapter 3) determined the metabolisable energy and standardised ileal digestible amino acids of two barley cultivars (NSH [normal starch hulled barley] and WSHL [waxy starch hull-less barley]) and wheat for broilers. These values were used to formulate the experimental diets in subsequent experiments that evaluated the optimum barley inclusion rate in wheat-based diets (Chapters 4 and 5), optimum barley particle size (Chapter 6) and conditioning temperature (CT; Chapter 7), and potential interaction of carbohydrases with each processing parameter. In Chapter 3, wheat and WSHL had the highest and lowest metabolisable energy and digestible amino acid contents, respectively, with NSH being intermediate. Supplemental carbohydrases increased the energy utilisation with a pronounced effect in WSHL. Data reported in Chapter 4 showed that optimum inclusion level of NSH was 283 g/kg of diet. Nutrient utilisation linearly improved with increasing inclusions of NSH. Carbohydrases improved feed per gain (F/G) and nutrient utilisation. Chapter 5 suggested that WSHL could be safely included up to 260 g/kg in a wheat-based diet with no adverse effect on growth performance. Carbohydrases improved the F/G and, starch and energy utilisation. In Chapter 6, particle size effect was preserved after pelleting and, coarse barley and carbohydrases improved the F/G and nutrient utilisation. The combination of carbohydrase and phytase produced no further improvements in nutrient utilisation. The final experiment (Chapter 7) demonstrated that better pellet quality achieved by increasing CT to 88 °C failed to ameliorate the negative impacts of high CT on nutrient utilisation and broiler performance. Carbohydrases improved weight gain, F/G and, starch and energy utilisation. The lack of interaction between the carbohydrases and CT indicated that carbohydrase had similar efficacy at each CT. The primary finding of this thesis research was that if cultivar-specific values for metabolisable energy and digestible amino acids are used in feed formulations, barley has the potential to substitute up to 50% of wheat in broiler diets. Coarse particle size (8.0 mm) and conditioning the diets up to 74 °C is recommended for the tested barley type. Supplemental carbohydrases improved the feeding value of barley for broilers.Item Dietary choices of New Zealand women during pregnancy and lactation : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Nutrition and Dietetics at Massey University, Albany, New Zealand(Massey University, 2020) Brown, Kimberley JaneBackground: A woman and her offspring’s health is affected by the maternal diet during pregnancy and lactation. Because of the importance of the diet, there is a large emphasis on women making optimal dietary choices, as recommended by specific guidelines, in pregnancy and lactation. Dietary recommendations are different from other life stages because of altered nutrient requirements and a heightened need for food safety practices. Currently, there is limited evidence available about dietary choices, food safety practices, and sources of nutrition information of New Zealand women during pregnancy and lactation. This information is important to inform strategies to improve the support that women receive during pregnancy and lactation as it identifies what recommendations are currently being effectively communicated. Aim: To investigate New Zealand women’s dietary choices, food safety practices, and sources of nutrition information during pregnancy and lactation. Methods: Women from New Zealand were invited to participate in this observational study between January and June 2019. Participants were required to be pregnant or within six months postpartum. Women completed a demographic, pregnancy food frequency, and food choice questionnaire during or retrospectively to their pregnancy. Postpartum women also completed a lactation food frequency and food choice questionnaire. Results: Women (n=458) consumed a range of foods from the four food groups (fruit and vegetables, breads and cereals, milk and milk products, and meat/meat alternatives/eggs). A large percentage reported adding or increasing, limiting, and avoiding foods. Cow’s milk, the most frequently daily consumed dairy product, was more commonly reported in pregnancy (93%) than lactation (64%). A range of fruit, vegetables, protein, and grain foods were consumed daily in pregnancy and lactation. The majority of women followed food safety recommendations in particular avoidance of alcohol (92%), raw milk products (86%), and raw/smoked/precooked fish/seafood (84%). Dietary information was acquired from a range of sources. The greatest dietary influences included midwives, New Zealand pregnancy and breastfeeding guidelines, and family/friends. Women also frequently reported receiving dietary advice from their lead maternal carer, handouts, the internet, and alternative health practitioners. During lactation, women received information from more potentially unreliable sources including family/ friends, the internet, and alternative health practitioners. Infant symptoms also frequently affected women’s food choices in lactation. Conclusion: Women implement significant dietary changes during pregnancy and lactation. Women are likely to add, remove, and limit food during pregnancy following the New Zealand pregnancy guidelines; advice from health professionals, the internet, magazines/books/newspapers; or because of food safety concerns. Lactating women are likely to make dietary changes because of infant symptoms or advice received from midwives, alternative health practitioners, family/ friends, and the internet.Item The role of vitamin D and Omega-3 long chain polyunsaturated fatty acids in children with Autism Spectrum Disorder : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Nutritional Science, Massey University, Albany, New Zealand(Massey University, 2018) Mazahery, HajarBackground: The efficacy of vitamin D and omega-3 long chain polyunsaturated fatty acid (omega-3 LCPUFA), each individually, in Autism Spectrum Disorder (ASD) has been tested in a few trials and the results are inconclusive. Furthermore, several observational studies have observed low vitamin D and omega-3 LCPUFA status in populations with ASD. Children with ASD are susceptible to nutritional issues and poor diet quality due to sensory, behavioural and gastrointestinal issues associated with the condition, though no information regarding these children’s nutritional status is available in New Zealand. Also, no validated nutritional quality assessment tools are available for this population. Aim and Objectives: The overall aim of this study was to investigate the role of vitamin D (VID), omega-3 LCPUFA (OM), or both (VIDOM) in ASD in children through systematically reviewing literature and conducting an intervention trial with these nutrients. The primary objective was to investigate the efficacy of vitamin D, omega-3 LCPUFA, both on core symptoms and sensory issues after correcting major nutritional deficiencies and secondary objectives were to investigate the efficacy of intervention on irritability and hyperactivity, to study dietary adequacy/nutritional status of children with ASD, and to validate a dietary Index of Children’s Eating (DICE) questionnaire against 4-day estimated food record (4DFR). Methods/Design: New Zealand children with ASD (age 2.5-8.0 years) participated in a 12-month randomised, double-blind, placebo-controlled, 2x2 factorial trial. Prior to trial entry, children’s dietary adequacy and nutritional status were assessed by 4DFR, DICE questionnaire (designed based on New Zealand Ministry of Health Food and Nutrition guidelines), and nutritional biomarkers (25(OH)D, red blood cell fatty acids, iron, calcium, albumin, vitamin B12, and folate). Data regarding dietary supplement use and special/exclusion diet, demographics and anthropometrics (height and weight) were also collected. Children then were randomly assigned to one of four treatment groups; daily 2000IU vitamin D3, 722 mg docosahexaenoic acid (DHA), both supplements, or placebo, and behaviours were assessed. Core symptoms were assessed using Social Responsiveness Scale (SRS), sensory issues using Sensory Processing Measure (SPM), problem behaviours including irritability and hyperactivity using Aberrant Behaviour Checklist (ABC). Outcome measures were analysed pre- and post-intervention. Pair-wise mixed effects longitudinal models were used for data analysis. Results: 309 families registered their interest in the study, of whom 190 families were either excluded or not enrolled. The children of remaining families (n=119) were screened for nutritional deficiencies and high serum 25(OH)D concentrations, of whom two children were excluded. Overall, 62% (73/117) of children completed the trial (placebo 16, VID 19, OM 23, VIDOM 15). The mean serum 25(OH)D concentrations (nmol/L) increased in the VID (27±14, P<0.001) and VIDOM (36±17, P<0.001) groups and changed slightly in the OM (1.1±14, P>0.05) and placebo (8.9±23, P>0.05) groups. The median omega-3 index (%) increased in the OM [4.4 (3.3, 5.9), P<0.001] and VIDOM [4.0 (2.0, 6.0), P<0.001] groups and decreased in the VID [-0.2 (-1.0, 0.1)] and placebo [-0.5 (-0.9, -0.1), P>0.05] groups. Compared to placebo, a greater improvement in multiple outcomes in the intervention groups was observed: SRS-social awareness for OM (0.4±2.9 vs. -1.4±2.3, P=0.03) and VIDOM (0.4±2.9 vs. -1.7±3.5, P=0.03); SRS-social communicative functioning for VIDOM (-5.6±10 vs. -16±24, P=0.07); SRS-total for OM (-5.8±12 vs. -17±18, P=0.08); SPM-taste and smell for VIDOM (-0.3±1.7 vs. -2.5±4.3, P=0.06), SPM-balance and motion for OM (-0.1±4.7 vs. -2.6±4.3, P=0.09), ABC-irritability for VID (0.8±6.1 vs. -4.0±4.9 P=0.01) and OM (0.8±6.1 vs. -5.0±5.0, P=0.001); and ABC-hyperactivity for VID (-0.8±5.6 vs. -5.2±6.3, P=0.047). Out of 86 children whose food records were available, approximately 50% (39/86) reported taking dietary supplements and 15% (13/86) were on a special/exclusion diet. A large proportion of children had dietary intake for vitamin D below the Adequate Intake (AI, 96%), protein below the Average Macronutrient Distribution Range (AMDR, 65%), and iodine below the Estimated Average Requirement (EAR, 54%). Dietary intake of fibre (43%) and vitamin E (37%) was also below the AI by at least one third of children. All or most children exceeded the recommendations for sodium (100%), total saturated fat (80%) and sugar (52%). There was a significant and positive correlation (r=0.7; P<0.001) and good agreement (ĸ=0.6) between total scores from DICE (64±16) and 4DFR (58±11). Participants in the highest tertile of DICE had higher intakes of magnesium (P=0.02), vitamin A (P=0.03) and fibre (P=0.06). Conclusions: Vitamin D and omega-3 LCPUFA, each individually or together, improved some behavioural symptoms of ASD. However, large attrition rates and resultant loss of statistical power preclude definitive conclusion and warrant further trials. Also, the baseline assessment of nutrition confirms nutritional issues and poor diet quality in children with ASD. Given the importance of nutrition in growth and development and in the management of ASD, screening of the nutritional status of children with ASD for nutrient adequacy to reduce under- or over-consumption of nutrients is recommended. DICE is a valid tool for the assessment of diet quality in children with ASD living in New Zealand.Item The barriers to surgical patients' oral intake in the acute hospital setting : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Nutrition and Dietetics, Massey University, Albany, New Zealand(Massey University, 2018) Stone, OliviaBackground: Hospital patients worldwide often do not eat all of their meals, resulting in suboptimal food intakes. These patients are more likely to experience numerous undesirable health outcomes as a consequence of not meeting their nutritional requirements. Aim: To investigate the barriers to surgical patients’ oral intake in an acute hospital setting in New Zealand (NZ). Objectives: To conduct a pilot study to test the usability of the validated Patient Mealtime and Nutrition Care Survey (PMNCS) in a NZ setting, and to adapt the PMNCS to include the most relevant barriers to oral intake in NZ. Further, to conduct a feasibility study to test the effectiveness of the NZ-PMNCS independently, and paired with patient meal observations to confirm the effectiveness of the tool. Methods/Design: A single-centre cross-sectional study conducted at North Shore Hospital, NZ. A sample of 100 surgical in-patients participated in the pilot study and 65 patients in the feasibility study. Results: The most frequently reported barriers were food brought into the hospital by visitors (81.5%) and a loss of appetite (70.8%). Six barrier domains were explored revealing significant findings for: younger (<65 years) compared to older (≥65 years) age associated with more hunger domain barriers (1.47 ± 0.81 versus 0.90 ± 0.67, P=0.003); longer (>5 days) versus shorter (≤5 days) length of stay associated with more food quality domain barriers (1.20 ± 1.26 versus 0.40 ± 0.81, P=0.003). Comparing the NZ-PMNCS and meal observation results showed that patients consuming ≤½ of their meals more frequently reported inability to make informed menu choices (50.0%)(P=0.027) and that consumption of their prescribed nutritional supplements affected their food intake negatively (50%)(P=0.001). Conclusion: Compared to earlier studies using previous versions of the PMNCS, the NZ-PMNCS captured similar results in the NZ hospital setting. Key issues identified include a younger age being associated with experiencing more hunger domain barriers, and patients consuming less food experienced difficulty choosing menu options and found prescribed nutritional supplements interfered with their food intake. The NZ-PMNCS was practical to use and feasible in identifying barriers to food intake. These findings could contribute to changing practices to improve hospital food intake. Keywords: barriers, oral intake, foodservice, surgical patients, hospitalItem The role of vegetables in the maintenance of acid-base balance and bone structure : a thesis presented in partial fulfillment of the requirements for the degree of Masters of Science in Nutritional Science at Massey University, Turitea, Palmerston North, New Zealand(Massey University, 2005) Singh, SewakhMetabolic acidosis may over time lead to osteoporosis by causing a release of calcium and other mineral phases from bone. The regular consumption of fruits and vegetables is believed to be associated with higher bone mineral density. In the last ten years various population-based studies have found positive effects of fruit and vegetable intakes on bone health. The aim of the present study was to investigate the effects of broccoli, onion, and potato on bone density and strength in male rats. Forty male Spraguc-Dawlcy rats were randomized into four equal groups of ten each. The animals were fed either a base, broccoli, onion, or potato diet for a period of eight weeks. The apparent percentage calcium and phosphorus retained, the serum type 1 collagen C-tclopcptide concentration, bone density and bone strength, and the urinary parameters i.e. ammonia, creatinine, urea, specific gravity and osmolality were determined. The groups on onion and potato diets had significantly higher apparent percentage calcium retained (over the balance period) than the group on control diet (p=0.02l and 0.008 respectively). Apparent percentage calcium retained was also significantly higher in the group on potato diet compared to the group on broccoli diet (p"0.037). There were no significant differences between groups for percentage phosphorus retained on ANOVA. However, the discriminant analysis (multivariate method) showed that the group on the broccoli diet retained significantly more phosphate over the balance period compared to the other groups. The urinary ammonia excretion (over the balance period) was significantly lower in the group on broccoli diet than in the groups on base and potato diets (p=0.040 and 0.055 respectively). As for the urinary urea excretion over the balance period, the group on base diet had significantly higher urea excretion than the groups on onion and potato diets (p=0.002 and p=0.000 respectively). Urinary urea excretion (over the balance period) was also significantly higher in the group on broccoli diet compared to the groups on onion and potato diets (p=0.005 and 0.000 respectively). The differences between groups for the volume of urine produced over the balance period were also significant i.e. the group on broccoli diet produced significantly more urine than the groups on base, onion, and potato diets (p=0.011. p=0.008. and p=0.00l respectively). However, there were no significant differences between groups for urinary specific gravity, osmolality, and creatinine, and bone density, bone breaking strength, and serum type I collagen C-telopeptide concentrations on ANOVA. In conclusion Ig of broccoli per day significantly reduced urinary ammonia excretion and increased apparent percentage phosphorus retained whereas Ig of onion or potato per day significantly increased apparent percentage calcium retained in growing male rats. The decrease in urinary ammonia excretion was most likely due to the buffering of metabolic acids by the bases present in broccoli resulting in decreased ammonia production and secretion. Similarly the increased apparent percentage phosphorus retained (in the group on broccoli diet) may be due to the bases present in broccoli that may have buffered metabolic acids thereby reducing the need for phosphate buffering. This increased apparent percentage phosphorus retained may also be due to a high pH which is known to enhance renal phosphate uptake. The buffering of metabolic acids by the bases present in onion and potato may have reduced the need for calcium buffering resulting in higher apparent percentage calcium retained in the groups on onion and potato diets. Thus broccoli, onion, and potato intake may protect against the bone depleting effects of an acidogenic diet and may also have the potential to increase bone mineral density.Item Limb growth and development in the endangered, captive reared, black stilt (Himantopus novaezelandiae) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology at Massey University, Turitea, Palmerston North, New Zealand(Massey University, 2006) Wrenn, Bridget JaneCaptive management is a crucial part of the conservation of one of New Zealand's endemic and critically endangered wading birds, the black still (Himantopus novaezelandiae). Acquired limb deformities have become apparent in captive reared black stilt, highlighting a lack of knowledge of normal limb growth and maturation. Body weight, and tarsus, carpal and remex length were measured on stilts on ad libitum and restricted fed diets. It was found that body weight, and carpal and remex length was significantly slowed by food restriction. Male stilts did not fully compensate in subsequent growth, whereas female stilts compensated in subsequent growth to greater than that of females previously on ad libitum diets. Food restriction also significantly increased the percentage of time stilts spent foraging and interacting with each other. Bone histology was undertaken on the tarsus and first phalanx of the wing. This data, combined with the morphological measurements enabled the identification of the critical growth periods, in which black stilt are most likely to develop limb abnormalities. These periods include: the first three weeks of age for leg abnormalities and between 13-25 days of age for wing abnormalities. The manganese (Mn) concentration in black stilt bone and feathers was also investigated. Key findings were that stilts with acquired limb deformities were not deficient in Mn, and feather Mn did not correlate with bone Mn concentration, and therefore can not be used as a non-invasive technique to monitor Mn bioavailability in the black stilt. The cause of angel wing and slipped tendon in captive reared black stilt was not resolved by the research. A Mn deficiency was eliminated but it is still uncertain whether rapid growth rates may have contributed to the abnormalities. This research has shown that dietary restriction in the early growth phase can be used to limit growth rates of black stilt, although the effects of this restriction on long term growth show sex-dependent differences. Further research into the incidence of limb abnormalities in the black stilt is encouraged, with the aim of contributing to the recovery of the critically endangered, wild population.Item Follow-up study of the dietary intake, anthropometric measurements, and blood pressure in children born to women in the Manawatu pregnancy study : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Nutritional Science at Massey University(Massey University, 2001) Al-Shami, EntesarWhen the proposal of the pilot study presented in this thesis was finally formulated, one of the first and important requirements was to obtain approval from accredited ethics committees. This proved to be a long and demanding process, but at the same time an interesting and useful experience. It was also somehow different from what was previously experienced in Kuwait, the researcher's home country. That was how the idea of presenting this thesis in two parts came into being. In the first part, the development of ethics codes and ethics committees was reviewed, a comparison of the process to obtain an ethical approval in New Zealand and in Kuwait was made, and the proposals presented to Massey University Human Ethics Committee (MUHEC) and to Manawatu-Whanganui Committee (MWEC) were outlined. Bioethics is a young discipline; the term "medical ethics" was first used at the beginning of the 19th century. However, codes of ethics of human research were only introduced towards the end of the first half of the 20th century. Hectic debates over these codes took place during the second half of the 20th century. On one side, there were growing concerns for the rights and safety of research participants, physically, psychologically and culturally, and on the other there were fears that scientific merits and benefits might be eroded by the limitations that research bioethics may enforce. These debates have resulted in amendments and changes in ethics codes, changes that probably will continue to develop during the 21st century. [From Introduction]Item The effects of berry juice on cognitive decline in older adults : a thesis presented in partial fulfilment of the requirements of Master of Arts in Psychology at Massey University, Palmerston North, New Zealand(Massey University, 2005) Holdaway, Melanie AnneThis study examined the effects of blackcurrant and boysenberry juices on cognitive processes in older adults. Current research suggests that fruits such as these may be able to reverse some of the effects of ageing on cognition. The free radical theory of ageing proposes that individuals age because oxidative damage accumulates in cells and interferes with cell functions. The hardest working tissues such as the brain accumulate the most oxidative damage through respiration. Antioxidants can protect against free radical formation and damage. Anthocyanins can contribute to half of the antioxidant capacity of deeply coloured berry fruit. An increase in dietary antioxidants such as anthocyanins may help to alleviate free radical damage within the brain. Research has shown that oxidative damage within the brain can impair cognitive functioning. Working memory shows age-related decline, along with visuospatial abilities, word retrieval and sustained attention. Some of this decline is thought to be related to oxidative damage of neurotransmitters such as acetylcholine and areas of the brain such as the hippocampus. Past research with humans has shown that some antioxidants can affect cognitive functioning in an older population. Animal studies have also established that diets enriched with anthocyanins can improve memory, motor control and neurotransmitter functioning. The present study involved giving berry juice drinks to 52 older adults that had been assessed as having a mild impairment of cognitive function. The participants were divided into three groups and drank 200mL a day of either blackcurrant juice, boysenberry juice or a placebo for twelve weeks. The participants were assessed at three different times over the course of the experiment using the RBANS. The RBANS is sensitive to small changes in its tests of memory, visuospatial ability, language and attention. The results of this study did not support previous research on antioxidants and cognitive functioning. There were no significant interactions between berry juices and any of the cognitive domains assessed by the RBANS over the course of the experiment. Some of the limitations of the study may be responsible for a lack of effect. The experiment was short with a low dose of antioxidants, and there was little control over the participants altering their own diet after being informed of the reasoning behind the study.