Fiona O'Leary

Vitamin B12 in Health and Disease

Vitamin B12 is essential for DNA synthesis and for cellular energy production.This review aims to outline the metabolism of vitamin B12, and to evaluate the causes and consequences of sub-clinical vitamin B12 deficiency. Vitamin B12 deficiency is common, mainly due to limited dietary intake of animal foods or malabsorption of the vitamin. Vegetarians are at risk of vitamin B12 deficiency as are other groups with low intakes of animal foods or those with restrictive dietary patterns. Malabsorption of vitamin B12 is most commonly seen in the elderly, secondary to gastric achlorhydria. The symptoms of sub-clinical deficiency are subtle and often not recognized. The long-term consequences of sub-clinical deficiency are not fully known but may include adverse effects on pregnancy outcomes, vascular, cognitive, bone and eye health.

Vitamin B12 status, cognitive decline and dementia: a systematic review of prospective cohort studies

Poor vitamin B₁₂ status may lead to the development of cognitive decline and dementia but there is a large variation in the quality, design of and results reported from these investigations. We have undertaken a systematic review of the evidence for the association between vitamin B₁₂ status and cognitive decline in older adults. A database search of the literature to 2011 was undertaken, using keywords related to vitamin B₁₂ and cognition. All prospective cohort studies assessing the association of serum vitamin B₁₂ or biomarkers were included. Quality assessment and extraction of the data were undertaken by two researchers. The quality assessment tool assigns a positive, neutral or negative rating. Of 3772 published articles, thirty-five cohort studies (n 14 325 subjects) were identified and evaluated. No association between serum vitamin B₁₂ concentrations and cognitive decline or dementia was found. However, four studies that used newer biomarkers of vitamin B₁₂ status (methylmalonic acid and holotranscobalamin (holoTC)) showed associations between poor vitamin B₁₂ status and the increased risk of cognitive decline or dementia diagnosis. In general, the studies were of reasonable quality (twenty-one positive, ten neutral and four negative quality) but of short duration and inadequate subject numbers to determine whether an effect exists. Future studies should be of adequate duration (at least 6 years), recruit subjects from the seventh decade, choose markers of vitamin B₁₂ status with adequate specificity such as holoTC and/or methylmalonic acid and employ standardised neurocognitive assessment tools and not screening tests in order to ascertain any relationship between vitamin B₁₂ status and cognitive decline.

Fruit consumption and adiposity status in adults: A systematic review of current evidence

ABSTRACT The aim of this review was to update current understanding of the potential association between fruit consumption and adiposity status in adult populations. Electronic databases were searched from January 1, 1997 to the search date of August 15, 2014, retrieving 4382 abstracts that were reviewed for eligibility: randomized controlled trial (RCT) or prospective cohort (PC), published in English, assessing the effect of whole fruit or fruit juice consumption on adiposity in healthy adult populations. Quality ratings for the 11 included RCTs were either positive (n = 2), neutral (n = 8), or negative (n = 1), while the six included PCs were either positive (n = 4) or neutral (n = 2). Consumption of whole fruit was found to contribute to a reduced risk for long-term weight gain in middle-aged adults. Experimental trials suggest this beneficial effect of whole fruit is mediated by a reduction in total energy intake. Fruit juice, however, had an opposing effect, promoting weight gain over the long term. This review reinforces national food-based dietary guidelines, encouraging the consumption of whole fruits and replacing fruit juices with plain water, as part of a broader set of dietary strategies to reduce total dietary energy intake in adult populations.

Comparison of single questions and brief questionnaire with longer validated food frequency questionnaire to assess adequate fruit and vegetable intake

OBJECTIVE The aim of this study was to determine if a single question (SQ) for fruit and a SQ or five-item questionnaire for vegetable consumption (VFQ) could replace a longer food frequency questionnaire (FFQ) to screen for inadequate versus adequate intakes in populations. METHODS Participants (109) completed three test screeners: fruit SQ, vegetable SQ, and a five-item VFQ followed by the reference 74-item FFQ (version 2 of the Dietary Questionnaire for Epidemiological Studies [DQESv2]) including 13 fruit and 25 vegetable items. The five-item VFQ asked about intake of salad vegetables, cooked vegetables, white potatoes, legumes, and vegetable juice. The screeners were compared with the reference (DQESv2 FFQ) for sensitivity, specificity, and positive and negative predictive powers (PPV, NPV) to detect intakes of two or more servings of fruit and three or more servings of vegetables. Relative validity was examined using Bland-Altman statistics. RESULTS The fruit SQ showed a PPV of 56% and an NPV of 83%. The PPV for the vegetable SQ was 30% and the NPV was 89%. For the five-item VFQ, the PPV was 39% and the NPV was 85%. Bland-Altman plots and linear regression equations showed that although the screener showed good agreement for fruit (unstandardized b1 coefficient = 0.04) for vegetable intake the difference between methods increased at higher intake levels (unstandardized b1 coefficients = -0.3 for the SQ, b1 = -0.6 for five-item VFQ). CONCLUSION The fruit SQ and the five-item VFQ are suitable replacements for longer FFQs to detect inadequate intake and assess population mean but not individual intakes.

Current practices of dietitians in the assessment and management of malnutrition in elderly patients

Aim This study aimed to determine the strategies used by dietitians to assess, treat and monitor elderly patients diagnosed with, or at increased risk of, malnutrition and to compare these with evidence-based guidelines and the current literature. Methods An online survey was distributed to members of the Dietitians Association of Australia (DAA) working in an inpatient/outpatient facility or private practice/consultancy. Dietitians working with elderly people (≥65 years old) were invited to participate. The survey was informed by DAAs evidence-based guidelines and was pre-tested. Responses of dietitians were analysed by years of experience, service setting and approaches taken to assess and manage malnutrition. Results One hundred sixty surveys were returned. Fourteen per cent of respondents worked in services that had no malnutrition policies. A Subjective Global Assessment tool was used by 59% of respondents and 95% recommended oral nutrition supplements when malnutrition or risk of malnutrition was diagnosed. Eighty-three per cent focused on increasing both energy and protein intake; however, 64% of respondents did not consider the nature of the protein source and only 62% discussed sarcopenia. Patients at risk of malnutrition were monitored slightly less frequently than those with diagnosed malnutrition. Conclusions Respondents generally use practices that align with current assessment and treatment practice guidelines and use validated assessment tools; however, at sites where no policies exist, protocols are needed. Treatment protocols exist in less than 50% of workplaces, suggesting that specific malnutrition treatment guidelines for the elderly may be needed.

Use of chicken eggshell to improve dietary calcium intake in rural sub-Saharan Africa

Abstract Undernutrition resulting from inadequate access to high‐quality, nutritious food is a widespread issue in sub‐Saharan Africa impacting the health and survival of mothers and their children. Inadequate dietary intake leads to a deficiency in nutrients including calcium, required for growth and physiological functioning. This study investigated the potential of increasing dietary calcium intake by the addition of heat‐treated ground eggshell to locally prepared food. A mixed methods approach of literature review, Delphi expert survey and focus group discussions with women of childbearing age in rural Tanzania, were used to assess the practicality, safety, and acceptability of consumption of ground eggshell. Chicken eggshell has high calcium content (380 mg of calcium/gram) and bioavailability comparable to calcium carbonate (~39%) with 1 g sufficient to provide one half of a sub‐Saharan African adult females dietary calcium needs. Salmonella was indicated as the most likely threat to human health through eggshell consumption. Experts agreed that eggshells boiled for 10 min when preparing hard‐boiled eggs with a further 20 min cooking of crushed eggshell in staple foods would eliminate identified egg‐associated pathogens. Five focus groups (n = 46) indicated eggshells were perceived as waste. However, there was an indication of general acceptance of the approach and a willingness to consider the incorporation of ground eggshells into their diets. Development of suitable communication methods are required to convey benefits and safe preparation methods. Ground eggshell could be a highly equitable method of increasing calcium intakes across rural sub‐Saharan Africa where calcium intake is low and village poultry ownership common.

The relationship between process use and stage of change for sugary drinks

BACKGROUND Decreasing sugar-sweetened beverage consumption may reduce obesity and obesity-related diseases. To better understand what processes could facilitate a reduction in sugary beverage intake, we examined the relationship between stage-of-change and use of 10 processes of change. Secondarily, reliability of the measure was assessed. METHODS A cross-sectional study was conducted, using a newly developed stage-of-change and process of change questionnaire. Participants (n = 105; male, n = 28) were aged between 18 and 60 years. A one-way analysis of variance, with Tukeys and Benjamini-Hochberg post hoc tests, was used to compare process use by stages. Paired t-tests were used to compare total cognitive and total behavioural process use within each stage. Cronbachs α coefficient and mean inter-item correlation was used to assess internal consistency. Reliability of repeated items was examined using kappa. RESULTS Cognitive and behavioural processes were used more in the contemplation/preparation and maintenance stages than in precontemplation (all P < 0.05). Compared to precontemplation, process use was significantly higher in contemplation/preparation for five individual processes, action for four processes and maintenance for five processes. The use of dramatic relief and self liberation was lower in maintenance than contemplation/preparation. Across the stages, the use of eight of the 10 processes differed. The use of consciousness raising, self re-evaluation and self liberation differed between stages more frequently than other processes. CONCLUSIONS The use of many processes differed by stage and could be incorporated into programmes aiming to assist adults in reducing their consumption of sugary drinks.

The relationship of diet to neurocognitive health: A systematic review

Background: Diet and nutrition may play an important role in neurocognitive health. Whether and how effective can single nutrients, or diet patterns be protective against neurocognitive decline, remains controversial. In this paper we review data from cohort studies, case-control studies and RCT relating either signal nutrients or dietary pattern to the risk of cognitive decline and dementia. We focus on the following six groups: caloric restriction, alcohol, vitamin B, antioxidants, fatty acids, and dietary patterns. Methods:We systematically reviewed selected modifiable dietary factors including calorie, alcohol, vitamin B, antioxidants, fatty acids, and dietary patterns that were studied in relation to neurocognitive health, including incident dementia. We searched MEDLINE, EMBASE and SCOPUS for published literature, excluding cross-sectional studies and laboratory trials. Analysis compared study finding consistency across factors, study designs e.g. population size, dosage of supplementation, age group and study-level characteristics. Results: In total, 90 studies were retrieved for systematic review. Research findings are mostly inconsistent even for those mostly studied compound such as vitamin B and antioxidant. Studies indicating daily energy deficit not significantly related to change in cognitive function except for DASH diet combined with a weight reduction program, however limited due to small sample size. A few RCT and cohort studies suggested no significant association between unsaturated fatty acids intake and incident dementia while others provide evidence of the opposite. Most studies found low to moderate alcohol intake lower risk of dementia. Dietary Patterns which is characterized by higher intake of fruits, vegetables, fish, nuts and legumes, and lower intake of meats and butter seemed to be associated with reduced risk of dementia. Conclusions: Conflicting data is found due to methodology issues. Further studies need focus on specific age group, adequate sample size and follow up years, subjects whose diet is assessed and monitored at an earlier stage and adequate dosage of supplementation on nutrient of interest.