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Featured researches published by Jk Pittaway.


Journal of The American Dietetic Association | 2008

Chickpeas may influence fatty acid and fiber intake in an ad libitum diet, leading to small improvements in serum lipid profile and glycemic control.

Jk Pittaway; Ik Robertson; Mj Ball

Optimal replacement macronutrient/s for dietary saturated fat to reduce cardiovascular disease risk remains controversial. Chickpeas are rich in dietary fiber and polyunsaturated fatty acids. This exploratory study, conducted from September 2004 to May 2005, assessed the effect of incorporating chickpeas in the ad libitum diet of 45 free-living adults. Participants consumed a minimum of 728 g of canned, drained chickpeas per week (the amount in four 300-g cans) as part of their habitual diet for 12 weeks (chickpea phase), followed by 4 weeks of habitual diet without chickpeas (usual phase). In the chickpea phase, mean dietary fiber intake was 6.77 g/day more and mean polyunsaturated fatty acid consumption (as a percentage of total fat) was 2.66% more (both P<0.001), causing the polyunsaturated to saturated fatty acids ratio to change from 0.39 to 0.47 (P=0.045). Serum total cholesterol and low-density lipoprotein cholesterol were 7.7 mg/dL (0.20 mmol/L) and 7.3 mg/dL (0.19 mmol/L) less, respectively, after the chickpea phase (P<or=0.01), fasting insulin was 0.75 microIU/mL (5.21 pmol/L) less (P=0.045), and the homeostasis assessment model of insulin resistance was 0.21 less (P=0.01). Univariate analysis revealed that dietary fiber had the greatest single effect, reducing serum total cholesterol by 15.8 mg/dL (0.41 mmol/L) (P=0.01). Polyunsaturated and saturated fatty acids had equivalent but opposing effects on serum total cholesterol and insulin. Larger studies on populations with greater degrees of hypercholesterolemia and/or hyperglycemia than the participants in this study are warranted.


Journal of The American College of Nutrition | 2007

Effects of a Controlled Diet Supplemented with Chickpeas on Serum Lipids, Glucose Tolerance, Satiety and Bowel Function

Jk Pittaway; Kiran D.K. Ahuja; Ik Robertson; Mj Ball

Objective: To compare the effect of a diet supplemented with chickpeas to a wheat-based diet of similar fibre content on serum lipids, glucose tolerance, satiety and bowel function. A third, lower-fibre wheat diet provided further information on dietary fibre quantity and bowel function and satiety. Method: Twenty-seven free-living adults followed two randomized, crossover dietary interventions each of five weeks duration. The chickpea diet included canned drained chickpeas, bread and shortbread biscuits containing 30% chickpea flour. The wheat diet included high-fibre wheat breakfast cereals and wholemeal bread. The diets were isoenergetic to the participants’ usual diet, matched for macronutrient content and controlled for dietary fibre. Following on from the second randomised intervention, a sub-group of 18 participants underwent a third, isoenergetic lower-fibre wheat diet that included low-fibre breakfast cereals and bread. Results: Repeated measures ANOVA revealed reductions in serum TC of 0.25 mmol/L (p < 0.01) and LDL-C of 0.20 mmol/L (p = 0.02) following the chickpea diet compared to the wheat. An unintended significant increase in PUFA and corresponding decrease in MUFA consumption occurred during the chickpea diet and statistical adjustment for this reduced but did not eliminate the effect on serum lipids. There was no significant difference in glucose tolerance. Perceived general bowel health improved significantly during the chickpea diet although there was considerable individual variation. Some participants reported greater satiety during the chickpea diet. Conclusions: The small but significant decrease in serum TC and LDL-C during the chickpea diet compared to the equivalent fibre wheat diet was partly due to unintentional changes in macronutrient intake occurring because of chickpea ingestion. If dietary energy and macronutrients were not controlled, chickpea consumption might result in greater benefits via influence on these factors.


Annals of Nutrition and Metabolism | 2006

Dietary Supplementation with Chickpeas for at Least 5 Weeks Results in Small but Significant Reductions in Serum Total and Low-Density Lipoprotein Cholesterols in Adult Women and Men

Jk Pittaway; Kdk Ahuja; M. Cehun; A. Chronopoulos; Ik Robertson; P.J. Nestel; Mj Ball

Aim: To compare the effects of a chickpea-supplemented diet and those of a wheat-supplemented diet on human serum lipids and lipoproteins. Methods: Forty-seven free-living adults participated in a randomized crossover weight maintenance dietary intervention involving two dietary periods, chickpea-supplemented and wheat-supplemented diets, each of at least 5 weeks duration. Results: The serum total cholesterol and low-density lipoprotein cholesterol levels were significantly lower (both p < 0.01) by 3.9 and 4.6%, respectively, after the chickpea-supplemented diet as compared with the wheat-supplemented diet. Protein (0.9% of energy, p = 0.01) and monounsaturated fat (3.3% of total fat, p < 0.001) intakes were slightly but significantly lower and the carbohydrate intake significantly higher (1.7% of energy, p < 0.001) on the chickpea-supplemented diet as compared with the wheat-supplemented diet. Multivariate analyses suggested that the differences in serum lipids were mainly due to small differences in polyunsaturated fatty acid and dietary fibre contents between the two intervention diets. Conclusions: Inclusion of chickpeas in an intervention diet results in lower serum total and low-density lipoprotein cholesterol levels as compared with a wheat-supplemented diet.


Appetite | 2010

Chickpea supplementation in an Australian diet affects food choice, satiety and bowel health

Catherine M. Murty; Jk Pittaway; Mj Ball

The study aimed to examine both changes in food consumption, satiation and perceived bowel health while consuming a diet rich in chickpeas, and participants, feelings about the dietary change. Forty-two participants completed an ordered crossover study, consuming their habitual diet for 4 weeks, a chickpea supplemented (average 104 g/day) diet for 12 weeks, and their habitual diet for another 4 weeks. Weighed dietary records were quantitatively analysed for changes in consumption of foods from within eight food groups. Perceived changes to bowel function and satiation were semi-quantitatively assessed using anchored visual analogue scales. Focus groups were used to qualitatively explore the acceptability of chickpea consumption and the benefits of, and barriers to, legume consumption for 15 participants. Intake of foods from all food groups was lower during the chickpea supplemented phase, particularly foods of the Cereal food group (P=0.01). Participants tended to eat more processed snack foods (high energy, low fiber) after ceasing chickpea consumption (P=0.09), a trend supported by focus group discussion. Perceived satiation increased while participants consumed chickpeas and perceived bowel function improved. Health benefits, increases in dietary variety and satiation with legume consumption were the main perceived benefits, while inconvenience and gastrointestinal upset discouraged legume consumption.


PLOS ONE | 2013

Make vitamin D while the sun shines, take supplements when it doesn't: a longitudinal, observational study of older adults in Tasmania, Australia.

Jk Pittaway; Kiran D.K. Ahuja; Jm Beckett; Ml Bird; Ik Robertson; Mj Ball

Low vitamin D status has been associated with a number of chronic conditions, particularly in older adults. The aim of this study was to identify how best to maintain optimum vitamin D status throughout the year in this high-risk population. The main objectives of the study were to assess seasonal vitamin D status; identify the main determinants of vitamin D status; determine if taking part in the study led to alterations in participant behaviour and vitamin D status. A longitudinal design across four consecutive seasons observed ninety-one 60–85 year old community-dwelling adults in Tasmania (41π S) over 13 consecutive months, with a follow-up assessment at next winters end. Associations between solar UVB exposure, sun protection behaviours, dietary and supplemental vitamin D with serum 25(OH)D concentrations were assessed. Variation in serum 25(OH)D demonstrated an identical pattern to solar UVB, lagging 8–10 weeks. Serum 25(OH)D was positively associated with summer UVB (mean 15.9 nmol/L; 95%CI 11.8–19.9 nmol/L, p<0.001) and vitamin D supplementation (100–600 IU/day: 95%CI 10.2 nmol/L; 0.8–19.6 nmol/L; p = 0.03; 800 IU/day: 21.0 nmol/L; 95%CI 8.1–34.0 nmol/L; p = 0.001). Seasonal variation in serum 25(OH)D was greatly diminished in supplement users. The most common alteration in participant behaviour after the study was ingesting vitamin D supplements. Post-study vitamin D supplementation ℘800 IU/day was seven times more likely than during the study resulting in mean difference in serum 25(OH)D between supplement and non-supplement users of 30.1 nmol/L (95%CI 19.4–40.8 nmol/L; p<0.001). The main limitation was homogeneity of participant ethnicity. Solar exposure in summer and ingestion of vitamin D supplements in other seasons are the most effective ways of achieving and maintaining year-round vitamin D sufficiency in older adults in the Southern hemisphere. Vitamin D supplementation has greatest effect on vitamin D status if ingested during and after winter, i.e. between the autumn and spring equinoxes.


Age and Ageing | 2013

Serum [25(OH)D] status, ankle strength and activity show seasonal variation in older adults: relevance for winter falls in higher latitudes

Ml Bird; Keith D. Hill; Ik Robertson; Mj Ball; Jk Pittaway; Ad Williams

BACKGROUND seasonal variation exists in serum [25(OH)D] and physical activity, especially at higher latitudes, and these factors impact lower limb strength. This study investigates seasonal variation in leg strength in a longitudinal repeated measures design concurrently with serum vitamin D and physical activity. METHODS eighty-eight community-dwelling independently mobile older adults (69.2 ± 6.5 years) were evaluated five times over a year, at the end of five consecutive seasons at latitude 41.1°S, recruited in two cohorts. Leg strength, serum [25(OH)D] and physical activity levels were measured. Time spent outside was recorded. Monthly falls diaries recorded falls. Data were analysed to determine annual means and percentage changes. RESULTS significant variation in [25(OH)D] (±15%), physical activity (±13%), ankle dorsiflexion strength (±8%) and hours spent outside (±20%) (all P < 0.001) was demonstrated over the year, with maximums in January and February (mid-summer). Low mean ankle strength was associated with increased incidence of falling (P = 0.047). Quadriceps strength did not change (±2%; P = 0.53). CONCLUSION ankle dorsiflexor strength varied seasonally. Increased ankle strength in summer may be influenced by increased levels of outdoors activity over the summer months. Reduced winter-time dorsiflexor strength may predispose older people to increased risk of tripping-related falls, and warrants investigation in a multi-faceted falls prevention programme.


International Journal of Environmental Research and Public Health | 2013

Age-Related Changes in Physical Fall Risk Factors: Results from a 3 Year Follow-up of Community Dwelling Older Adults in Tasmania, Australia

Ml Bird; Jk Pittaway; Isobel Cuisick; Megan Rattray; Kiran D.K. Ahuja

As the population ages, fall rates are expected to increase, leading to a rise in accidental injury and injury-related deaths, and placing an escalating burden on health care systems. Sixty-nine independent community-dwelling adults (60–85 years, 18 males) had their leg strength, physical activity levels and their annual fall rate assessed at two timepoints over three years, (summer 2010 and summer 2013) monitoring balance. Force platform measures of medio-lateral sway range increased significantly under conditions of eyes open (mean difference MD 2.5 cm; 95% CI 2.2 to 2.8 cm) and eyes closed (MD 3.2 cm; 95% CI 2.8 to 3.6 cm), respectively (all p < 0.001) indicating worsening static balance control. Dynamic balance showed similar changes (p < 0.036). Leg strength was not significantly different between visits (p > 0.26). Physical activity reduced significantly (MD −909 Cal/week; 95% CI −347 to −1,470 Cal/week; p = 0.002) during the course of the study. Participants maintained aerobic activities, however resistance and balance exercise levels decreased non-significantly. The likelihood of falling was higher at the end of the study compared to the first timepoint (odds ratio 1.93, 95% CI 0.94 to 3.94; p = 0.07). Results of this study indicate that despite maintenance of leg strength there was an increase in medio-lateral sway over a relatively short time frame, with higher than expected increases in fall rates.


Journal of Ethnopharmacology | 2011

In vitro antioxidant, antiplatelet and anti-inflammatory activity of Carpobrotus rossii (pigface) extract

Dp Geraghty; Kiran D.K. Ahuja; Jk Pittaway; Cecilia M. Shing; Ga Jacobson; Nynke Jager; Sasa Jurkovic; Ck Narkowicz; Cassandra Im Saunders; Mj Ball; Alex Pinkard; Raghu R. Vennavaram; Mj Adams

ETHNOPHARMACOLOGICAL RELEVANCE Carpobrotus rossii (CR) has a history of use as a food and therapeutic agent by Australian indigenous peoples and early European settlers and is believed to contain a number of pharmacologically active polyphenolic compounds. AIMS OF THE STUDY Oxidation of low density lipoprotein (LDL), platelet aggregation, and inflammation contribute to the development and progression of atherosclerosis. The aim of the present study was to investigate the antioxidant, antiplatelet and anti-inflammatory activity of CR extract using human blood components. MATERIALS AND METHODS An assay employing in vitro copper-induced oxidation of serum lipids was used to assess antioxidant activity of CR extract (and tannin, flavonoid and pre- and post-flavonoid fractions). The effects of CR extract on ADP- and collagen-induced platelet aggregation, and on basal (unstimulated) and lipopolysaccharide (LPS)- and phytohaemagglutinin A (PHA)-stimulated cytokine release from peripheral blood mononuclear cells (PBMC) were also investigated. RESULTS CR extract increased the lag time of serum oxidation (maximum of ∼4-fold at 20μg/ml) in a concentration-dependent manner. The antioxidant activity resided only in the tannin and post-flavonoid fractions. CR had no effect on ADP-induced platelet aggregation, but significantly decreased collagen-induced platelet aggregation. LPS, but not PHA, significantly increased the release of IL-1β and TNF-α from PBMC. CR extract alone inhibited monocyte chemoattractant protein (MCP)-1 release and in the presence of LPS, inhibited IL-10, TNF-α and MCP-1 release compared to LPS alone. CONCLUSION CR has significant in vitro antioxidant, antiplatelet and, potentially, anti-inflammatory activity.


Journal of Aging Research | 2013

The Association between Seasonal Variation in Vitamin D, Postural Sway, and Falls Risk: An Observational Cohort Study

Ml Bird; Keith D. Hill; Ik Robertson; Mj Ball; Jk Pittaway; Ad Williams

Introduction. Low serum vitamin D levels are associated with increased postural sway. Vitamin D varies seasonally. This study investigates whether postural sway varies seasonally and is associated with serum vitamin D and falls. Methods. In a longitudinal observational study, eighty-eight independently mobile community-dwelling older adults (69.7 ± 7.6 years) were evaluated on five occasions over one year, measuring postural sway (force platform), vitamin D levels, fall incidence, and causes and adverse outcomes. Mixed-methods Poisson regression was used to determine associations between measures. Results. Postural sway did not vary over the year. Vitamin D levels varied seasonally (P < 0.001), peaking in summer. Incidence of falls (P = 0.01) and injurious falls (P = 0.02) were lower in spring, with the highest fall rate at the end of autumn. Postural sway was not related to vitamin D (P = 0.87) or fall rates, but it was associated with fall injuries (IRR 1.59 (CI 1.14 to 2.24, P = 0.007). Conclusions. Postural sway remained stable across the year while vitamin D varied seasonally. Participants with high values for postural sway demonstrated higher rates of injurious falls. This study provides important evidence for clinicians and researchers providing interventions measuring balance outcomes across seasons.


Journal of Nutrition Health & Aging | 2015

Omega-3 dietary Fatty Acid status of healthy older adults in Tasmania, Australia: an observational study.

Jk Pittaway; L. T. Chuang; Kiran D.K. Ahuja; Jm Beckett; R. H. Glew; Mj Ball

ObjectivesTo determine the dietary and supplement intake of omega-3 (n-3) polyunsaturated fatty acids (PUFA) of older Tasmanian adults; their plasma n-3 PUFA status and the relationship between n-3 PUFA intake and plasma status.DesignCross-sectional study.SettingLaunceston and surrounding regions, Tasmania, Australia.ParticipantsSeventy-three community-dwelling older adults: 23 men aged 70 ± 6.1 years and 50 women aged 70 ± 6.7 years.MeasurementsA validated, semi-quantitative food frequency questionnaire estimated dietary PUFA intake. The plasma phospholipid fraction of venous blood samples was analysed for fatty acid content. Anthropometric data was recorded.ResultsThirty-five participants (48%) regularly ingested a fish oil supplement. Their plasma n-3 PUFA profile contained significantly more eicosapentaenoic acid (EPA) (odds ratio 3.14; 95% CI 1.37% to 7.30%; p<0.05) and docosahexaenoic acid (DHA) (odds ratio 2.64; 95% CI 1.16% to 6.01%; p<0.05) than non-supplement users. Fish and meat were the main dietary sources of n-3 PUFAs. Participants most commonly consumed fish 3–4 times per week. Significant associations of dietary α-linolenic acid (ALA), EPA, docosapentaenoic acid (DPA) and DHA with plasma n-3 PUFAs were noted but not always between dietary and plasma counterparts.ConclusionWithout the use of fish oil supplements, most study participants were unable to meet the recommended daily intake of 0.5g EPA and DHA combined; however, the plasma n-3 PUFA profile of non-supplement-users was still robust compared to other Australian and overseas studies.

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Mj Ball

University of Tasmania

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Jm Beckett

University of Tasmania

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Kdk Ahuja

University of Tasmania

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