Papers by Anne-Thea McGill
Obesity Research & Clinical Practice, Oct 1, 2012
Ožirenie i Metabolizm, Dec 15, 2009
Low serum 25 hydroxyvitamin D 3 (vitamin D 3) is known to perturb cellular function in many tissu... more Low serum 25 hydroxyvitamin D 3 (vitamin D 3) is known to perturb cellular function in many tissues, including the endocrine pancreas, which are involved in obesity and type II diabetes mellitus (TIIDM). Vitamin D 3 insufficiency has been linked to obesity, whether obesity is assessed by body mass index (BMI) or waist circumference (waist). Central obesity, using waist as the surrogate, is associated with the metabolic syndrome (MetSyn), insulin resistance, TIIDM and atherosclerotic cardiovascular disease (CVD). We tested how vitamin D 3 was related to measures of fat mass, MetSyn markers, haemoglobin A 1c (HbA 1c) and MetSyn in a cross-sectional sample of 250 overweight and obese adults of different ethnicities. There were modest inverse associations of vitamin D 3 with body weight (weight) (r =-0.21, p = 0.0009), BMI (r =-0.18, p = 0.005), waist (r =-0.14, p = 0.03), [but not body fat % (r =-0.08, p = 0.24)], and HbA 1c (r =-0.16, p = 0.01). Multivariable regression carried out separately for BMI and waist showed a decrease of 0.74 nmol/ L (p = 0.002) in vitamin D 3 per 1 kg/m 2 increase in BMI and a decrease of 0.29 nmol/L (p = 0.01) per 1 cm increase in waist, with each explaining approximately 3% of the variation in vitamin D 3 over and above gender, age, ethnicity and season. The similar relationships of BMI and waist with vitamin D 3 may have been due to associations between BMI and waist, or coincidental, where different mechanisms relating hypovitaminosis D 3 to obesity occur concurrently. Previously reviewed mechanisms include that 1) low vitamin D 3 , may impair insulin action, glucose metabolism and various other metabolic processes in adipose and lean tissue 2) fat soluble-vitamin D 3 is sequestered in the large adipose compartment, and low in serum, 3) obese people may be sensitive about their body shape, minimising their skin exposure to view and sunlight (not tested). We showed evidence for the first theory but no evidence to support the second. In the current study, serum vitamin D 3 was inversely related to weight, BMI and markers of TIIDM (large waist, raised HbA 1c) but not to adipose mass nor to MetSyn per se.
Archives of public health, Sep 1, 2014
Metabolic syndrome (MetS) predicts type II diabetes mellitus (TIIDM), cardiovascular disease (CVD... more Metabolic syndrome (MetS) predicts type II diabetes mellitus (TIIDM), cardiovascular disease (CVD) and cancer, and their rates have escalated over the last few decades. Obesity related co-morbidities also overlap the concept of the metabolic syndrome (MetS). However, understanding of the syndrome's underlying causes may have been misapprehended. The current paper follows on from a theory review by McGill, AT in Archives of Public Health, 72: 30. This accompanying paper utilises research on human evolution and new biochemistry to theorise on why MetS and obesity arise and how they affect the population. The basis of this composite unifying theory is that the proportionately large, energy-demanding human brain may have driven co-adaptive mechanisms to provide, or conserve, energy for the brain. A 'dual system' is proposed. 1) The enlarged, complex cortico-limbic-striatal system increases dietary energy by developing strong neural self-reward/motivation pathways for the acquisition of energy dense food, and (2) the nuclear factor-erythroid 2-related factor 2 (NRF2) cellular protection system amplifies antioxidant, antitoxicant and repair activity by employing plant chemicals. In humans who consume a nutritious diet, the NRF2 system has become highly energy efficient. Other relevant human-specific co-adaptations are explored. In order to 'test' this composite unifying theory it is important to show that the hypothesis and sub-theories pertain throughout the whole of human evolution and history up till the current era. Corollaries of the composite unifying theory of MetS are examined with respect to past under-nutrition and malnutrition since agriculture began 10,000 years ago. The effects of man-made pollutants on degenerative change are examined. Projections are then made from current to future patterns on the state of 'insufficient micronutrient and/or unbalanced high energy malnutrition with central obesity and metabolic dysregulation' or 'malnubesity'. Forecasts on human health are made on positive, proactive strategies using the composite unifying theory, and are extended to the wider human ecology of food production. A comparison is made with the outlook for humans if current assumptions and the status quo on causes and treatments are maintained. Areas of further research are outlined. A table of suggestions for possible public health action is included.
Relationships of low serum vitamin D3 with anthropometry and markers of the metabolic syndrome an... more Relationships of low serum vitamin D3 with anthropometry and markers of the metabolic syndrome and diabetes in overweight and obesity
Physiology & Behavior, 2010
High-fat diets are associated with obesity, and the weak satiety response elicited in response to... more High-fat diets are associated with obesity, and the weak satiety response elicited in response to dietary lipids is likely to play a role. Preliminary evidence from studies of medium (MCT) and long chain triglycerides (LCT) supports greater appetite suppression on high-MCT diets, possibly a consequence of direct portal access, more rapid oxidation and muted lipaemia. No data is as yet available on high-SCT diets which also have direct hepatic access. In this study SCT-(dairy fats), MCT-(coconut oil) and LCT-enriched (beef tallow) test breakfasts (3.3 MJ) containing 52 g lipid (58 en% fat) were investigated in a randomized, cross-over study in 18 lean men. All participants were required to complete the 3 study days in randomised order. Participants rated appetite sensations using visual analogue scales (VAS), and energy intake (EI) was measured by covert weighing of an ad libitum lunch meal 3.5 h postprandially. Blood samples were collected by venous cannulation. There were no detectable differences between breakfasts in perceived pleasantness, visual appearance, smell, taste, aftertaste and palatability (P N 0.05). There was no significant effect of fatty acid chain length on ratings of hunger, fullness, satisfaction or current thoughts of food, nor did energy (mean, sem: SCT: 4406, 366 kJ; MCT: 4422, 306 kJ; LCT: 4490, 324 kJ; P N 0.05) or macronutrient intake at lunch differ between diets. The maximum difference in EI between diets was less than 2%. Postprandial lipaemia also did not differ significantly. We conclude that there was no evidence that fatty acid chain length has an effect on measures of appetite and food intake when assessed following a single high-fat test meal in lean participants.
The New Zealand Medical Journal, Mar 19, 2010
Giving an (artificial) agent that does no overt or immediate harm, but no good either, is not ade... more Giving an (artificial) agent that does no overt or immediate harm, but no good either, is not adequate. On further examination, there appear to be a range of concerns with agents generally assumed to help weight loss and obesity related disease. These include food additives designed to enhance qualities such as sweetness. These additives are variably tested for toxicity, efficacy yet extensively for industrial application. Also problematic are modified food extracts (nutraceuticals), alternative therapies, supplements (vitamin, mineral and other) and drugs. Some of these agents may not even be harmless or stop weight gain, and some have noticeable adverse effects.
Metabolic brain disease mainly results from inborn metabolic errors, primarily from enzymatic def... more Metabolic brain disease mainly results from inborn metabolic errors, primarily from enzymatic defects which lead to substrate accumulation, product reduction, or increase in toxic metabolites through alternate pathways. The majority of these conditions are familial, however spontaneous mutation may also occur in utero. Acquired or inborn metabolic brain diseases that produce brain dysfunction or damage. These include primary (i.e., disorders intrinsic to the brain) and secondary (i.e., extracranial) metabolic conditions that adversely affect cerebral function. Brain dysfunction or damage caused by acquired (i.e., non-inborn) metabolic disorders. Associated conditions include endocrine diseases; water-electrolyte imbalance; kidney diseases; liver diseases; anoxia (hypoxia, brain); nutritional disorders; an encephalopathy associated with hemodialysis; and other disorders. In the present book, twelve typical literatures about metabolic brain disease published on international authori...
Authors' original file for figure 1
Journal of primary health care, Dec 1, 2016
INTRODUCTION Nutrition care refers to practices conducted by health professionals to support pati... more INTRODUCTION Nutrition care refers to practices conducted by health professionals to support patients to improve their dietary intake. General practitioners (GPs) are expected to provide nutrition care to patients for prevention and management of chronic disease. AIM This study explores GPs' opinions regarding nutrition care provision to patients with chronic disease. METHODS An interpretive descriptive approach to qualitative research using seven semi-structured focus groups with 48 GPs in Auckland was used. Focus groups investigated how GPs felt about providing nutrition care; the perceived barriers to and support required for this care; the development of further nutrition knowledge and skills; and possible roles for Practice Nurses. Recorded interviews were transcribed verbatim and analysed using a thematic approach. RESULTS GPs indicated routine provision of basic nutrition care to patients with chronic disease, but perceived their limited consultation time and nutrition co...
Physiology & Behavior, 2012
The lipid emulsion Fabuless (Olibra) has been shown in some studies to decrease short/medium term... more The lipid emulsion Fabuless (Olibra) has been shown in some studies to decrease short/medium term energy intake (EI) and prevent weight regain. The purported mechanism is the ileal brake. Whether Fabuless is efficacious under a range of dietary conditions is unknown since studies have administered the emulsion within a fermented, semi-liquid dairy yoghurt, and outcomes have been inconsistent. To determine whether Fabuless suppresses post-ingestive satiety and short-term food intake under a range of dietary conditions and forms we administered the emulsion co-presented with 185 mL water, stirred into a semi-liquid dairy yoghurt, and co-presented with a solid food breakfast muffin. This was a cross-over study in 18 lean men randomised to 6 treatments: (i) lipid emulsion, LE (15 g Fabuless, containing 4.2g lipid, 0.2 MJ)+water, (ii) lipid control, LC (15 g non-emulsified lipid/water, containing 4.2g lipid, 0.2 MJ)+water, (iii) lipid emulsion+yoghurt, LE+Y (1.2 MJ), (iv) lipid control+yoghurt, LC+Y (1.2 MJ), (v) lipid emulsion+muffin, LE+M (1.2 MJ), (vi) lipid control+muffin, LC+M (1.2 MJ), each given as a test breakfast at 8.30 am. Participants rated postprandial appetite sensations using visual analogue scales (VAS), and ad libitum energy intake was measured at a lunch meal 3.5h later. The lipid emulsion increased fullness compared with an energy-matched lipid control but only when administered within the semi-liquid fermented yoghurt (P<0.05). There were no effects on satiety ratings when co-presented with water or with the solid food muffin. Energy and macronutrient intake were not significantly decreased by any of the emulsion treatments. We conclude that effects are small, the format in which lipid emulsions are consumed influences postprandial satiety, and there is no evidence that this emulsion alters eating behaviour at the subsequent meal.
Focus on Alternative and Complementary Therapies, 2010
McGill A-T, Wake G Beedle A. Energy and Nutrient Modelling of Human Evolution. (Poster, Abstract ... more McGill A-T, Wake G Beedle A. Energy and Nutrient Modelling of Human Evolution. (Poster, Abstract Number P56) Proceedings of the Australia and New Zealand Obesity Society Annual Scientific Meeting (ANZOS ASM) Sydney, Australia. Oct 2010. Obesity Research and Clinical Practice 4 (Suppl 1): S28,2010 McGill A-T, Stewart JM, Lithander FE and Poppitt SD. (Oral, Abstract Number S39) Interrelationships of changes in weight and metabolic syndrome. Proceedings of the Australia and New Zealand Obesity Society Annual Scientific Meeting (ANZOS ASM) Sydney, Australia. Oct 2010. Obesity Research and Clinical Practice 4 (Suppl 1): S28,2010 McGill A-T, Stewart JM, Lithander FE and Poppitt SD (Poster Abstract) Vitamin E in the Metabolic Syndrome. Proceedings of the Australia and New Zealand Obesity Society Annual Scientific Meeting (ANZOS ASM) part of the Health and Medical Research Council Meeting. Brisbane, Australia. Nov 2008. McGill A-T, Stewart JM, Lithander FE and Poppitt SD (Poster Abstract) A...
BACKGROUND The prevalence of obesity has increased substantially over recent decades and is assoc... more BACKGROUND The prevalence of obesity has increased substantially over recent decades and is associated with considerable health inequalities. Although the causes of obesity are complex, key drivers include over-consumption of highly palatable, energy-dense and nutrient-poor foods, which have a profound impact on the composition and function of the gut microbiome. Alterations to the microbiome may play a critical role in obesity by affecting energy extraction from food and subsequent energy metabolism and fat storage. OBJECTIVE We report the study protocol and recruitment strategy of the PROMISE (PRedictors linking Obesity and the gut MIcrobiomE) study, which characterises the gut microbiome in two populations with markedly different metabolic disease risk (Pacific and European women) and different body fat profiles (normal and obese). It investigates: (1) the role of gut microbiome composition and functionality in obesity and body fat distribution; and (2) the interactions between d...
No evidence of differential effects of SFA, MUFA or
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Papers by Anne-Thea McGill