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Reversing the immune ageing clock: lifestyle modifications and pharmacological interventions.
Duggal, NA
Biogerontology. 2018;19(6):481-496
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Advancing age is accompanied by a compromised ability of older adults to combat bacterial and viral infections, increased risk of autoimmunity, poor vaccination responses and the re-emergence of latent infections. This review discusses current understanding of immunesenescence [the gradual deterioration of our immune system as we get older] and also focuses on lifestyle interventions and therapeutic strategies that have been shown to restore immune functioning in aged individuals. Findings show that: - changes in nutrition and lifestyle can be an effective approach towards improving immune outcome in older adults but may be hard to achieve at a population level. - improving immune responses, such as the developments of vaccines, may be used as an early biomarker for anti-ageing effects. Authors conclude that immunomodulation represents a promising therapeutic approach to improve the health of older adults.
Abstract
It is widely accepted that ageing is accompanied by remodelling of the immune system, including reduced numbers of naïve T cells, increased senescent or exhausted T cells, compromise to monocyte, neutrophil and natural killer cell function and an increase in systemic inflammation. In combination these changes result in increased risk of infection, reduced immune memory, reduced immune tolerance and immune surveillance, with significant impacts upon health in old age. More recently it has become clear that the rate of decline in the immune system is malleable and can be influenced by environmental factors such as physical activity as well as pharmacological interventions. This review discusses briefly our current understanding of immunesenescence and then focuses on lifestyle interventions and therapeutic strategies that have been shown to restore immune functioning in aged individuals.
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Navy Beans Impact the Stool Metabolome and Metabolic Pathways for Colon Health in Cancer Survivors.
Baxter, BA, Oppel, RC, Ryan, EP
Nutrients. 2018;11(1)
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Colorectal cancer (CRC) is one of the leading cause of cancer-related death around the world. Emerging evidence supports that increased consumption of pulses / legumes, such as navy beans, can reduce risk. Consuming navy beans as part of one's diet has been previously shown to positively affect the relationship between a person's gut bacteria and their health status. This study looked at stool samples to assess the impact of navy bean consumption on health based on the by-products of metabolism generated by gut bacteria (metabolites). The study was a 4-week, randomised-controlled trial with overweight and obese CRC survivors and involved consumption of 1 meal and 1 snack daily. People in the intervention group ate 35g of cooked navy bean daily whereas those in the control group had 0g of navy beans. From amongst the hundreds of metabolites identified in both groups, there was a 5-fold increase in ophthalmate for navy bean consumers, which can indicate an increase in glutathione. Glutathione is an antioxidant and detoxifying substance produced in the human liver. It is involved in cancer control mechanisms such as detoxification of xenobiotics (toxins), antioxidant defense, proliferation, and apoptosis. Other interesting results include the metabolism of the amino acid lysine, which supports health immune function, and an increase in plant-based nutrients or phytochemicals in those who consumed navy bean vs the control group. These results are indicative of an acute response to increased navy bean intake, which merit further investigation for improving colonic health after long-term consumption.
Abstract
Colorectal cancer (CRC) is the third leading cause of cancer-related death in the United States and emerging evidence supports that increased consumption of legumes, such as navy beans, can reduce risk. Navy bean consumption was previously shown to modulate host and microbiome metabolism, and this investigation was performed to assess the impact on the human stool metabolome, which includes the presence of navy bean metabolites. This 4-week, randomized-controlled trial with overweight and obese CRC survivors involved consumption of 1 meal and 1 snack daily. The intervention contained 35 g of cooked navy bean or macronutrient matched meals and snacks with 0 g of navy beans for the control group (n = 18). There were 30 statistically significant metabolite differences in the stool of participants that consumed navy bean at day 28 compared to the participants' baseline (p ≤ 0.05) and 26 significantly different metabolites when compared to the control group. Of the 560 total metabolites identified from the cooked navy beans, there were 237 possible navy bean-derived metabolites that were identified in the stool of participants consuming navy beans, such as N-methylpipecolate, 2-aminoadipate, piperidine, and vanillate. The microbial metabolism of amino acids and fatty acids were also identified in stool after 4 weeks of navy bean intake including cadaverine, hydantoin-5 propionic acid, 4-hydroxyphenylacetate, and caprylate. The stool relative abundance of ophthalmate increased 5.25-fold for navy bean consumers that can indicate glutathione regulation, and involving cancer control mechanisms such as detoxification of xenobiotics, antioxidant defense, proliferation, and apoptosis. Metabolic pathways involving lysine, and phytochemicals were also modulated by navy bean intake in CRC survivors. These metabolites and metabolic pathways represent an acute response to increased navy bean intake, which merit further investigation for improving colonic health after long-term consumption.
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Association between eating behaviour and diet quality: eating alone vs. eating with others.
Chae, W, Ju, YJ, Shin, J, Jang, SI, Park, EC
Nutrition journal. 2018;17(1):117
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Selecting foods for a day is easily influenced by the social environment and eating together or alone plays a big role in that decision. The study aims to evaluate the association between diet quality of the modern Korean adult population based on the eating behaviour and the socioeconomic factors that influence their diet quality. The study is a cross-sectional study which included 3365 men and 5258 women aged between 19 and 64 years. The study included demographic, socioeconomics, and health behaviour factors as covariates. Results indicate that diet quality is influence by eating behaviour. Authors observed that when Korean adults ate without a companion, their diet quality was significantly lower than those who consistently ate with others. Furthermore, from the higher education to lower education level, the diet quality declined when they eat alone. Authors conclude that many Korean adults are experiencing low diet quality when they eat alone. The study provides evidence to promote interventions to improve diet quality among the public.
Abstract
BACKGROUND To discover the association between eating alone and diet quality among Korean adults who eat alone measured by the mean adequacy ratio (MAR), METHODS The cross-sectional study in diet quality which was measured by nutrient intakes, indicated as MAR and nutrient adequacy ratio (NAR) with the Korean National Health and Nutrition Examination Survey (KNHANES) VI 2013-2015 data. Study population was 8523 Korean adults. Multiple linear regression was performed to identify the association between eating behaviour and MAR and further study analysed how socioeconomic factors influence the diet quality of those who eat alone. RESULTS We found that the diet quality of people who eat alone was lower than that of people who eat together in both male (β: - 0.110, p = 0.002) and female participants (β: - 0.069, p = 0.005). Among who eats alone, the socioeconomic factors that negatively influenced MAR with the living arrangement, education level, income levels, and various occupation classifications. CONCLUSIONS People who eat alone have nutrition intake below the recommended amount. This could lead to serious health problems not only to those who are socially disadvantaged but also those who are in a higher social stratum. Policy-makers should develop strategies to enhance diet quality to prevent potential risk factors.
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Sourdough Fermentation Favorably Influences Selenium Biotransformation and the Biological Effects of Flatbread.
Di Nunzio, M, Bordoni, A, Aureli, F, Cubadda, F, Gianotti, A
Nutrients. 2018;10(12)
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Selenium (Se) is a soil-based trace element essential for immune system functionality, hormone regulation and muscular metabolism, however several regions in the world are deficient in Se. The current approach to this global health issue is fortification with Se-enriched flour, but this comes with its trials due to a small range between deficiency and toxicity. The primary aim of this study was to identify whether sourdough fermentation increases the bioavailability of Se in a typical flatbread. Flatbreads were prepared with either control wheat flour or inorganic Se-enriched wheat flour, and both were subject to conventional and sourdough fermentation. The variations were submitted to in vitro simulation human digestion and the biological effect of products were tested using cultured liver cells. This study found the use of Se-enriched flour significantly increased Se content of the flatbread. Sourdough fermentation, compared with conventional fermentation, led to a major conversion of inorganic Se present in the flour into the organic species, which is significantly more available for absorption. Based on these results, the authors conclude sourdough fermentation is a strategy that should be utilised to improve Se deficiency throughout the world.
Abstract
Although selenium is of great importance for the human body, in several world regions the intake of this essential trace element does not meet the dietary reference values. To achieve optimal intake, fortification of bread by using selenium-enriched flour has been put forward. Less is known on the potential effect of sourdough fermentation, which might be worth exploring as the biological effects of selenium strongly depend on its chemical form and sourdough fermentation is known to cause transformations of nutrients and phytochemicals, including the conversion of inorganic selenium into organic selenocompounds. Here we investigated the bio transformation of selenium by sourdough fermentation in a typical Italian flatbread (piadina) made with standard (control) or selenium-enriched flour. The different piadina were submitted to in vitro digestion, and the biological activity of the resulting hydrolysates was tested by means of cultured human liver cells exposed to an exogenous oxidative stress. The use of selenium-enriched flour and sourdough fermentation increased the total content of bioaccessible selenium in organic form, compared to conventional fermentation, and led to protective effects counteracting oxidative damage in cultured cells. The present study suggests that selenium-rich, sourdough-fermented bakery products show promise for improving human selenium nutrition whenever necessary.
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SunGold Kiwifruit Supplementation of Individuals with Prediabetes Alters Gut Microbiota and Improves Vitamin C Status, Anthropometric and Clinical Markers.
Wilson, R, Willis, J, Gearry, RB, Hughes, A, Lawley, B, Skidmore, P, Frampton, C, Fleming, E, Anderson, A, Jones, L, et al
Nutrients. 2018;10(7)
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Increased plasma glucose levels are linked with increased oxidative stress. An increase in the uptake of antioxidants such as vitamin C through diet has been demonstrated by several studies as contributing to the maintenance of normal glucose levels and reducing the risk factors for Type 2 diabetes. The aim of this study was to investigate the vitamin C status, anthropometric measurements and faecal microbiota of an individual on consumption of high vitamin C kiwi fruit for a period of 12 weeks. Baseline measures were compared at the end of 12 weeks resulting in significant increase in plasma vitamin C status (14 µmol/L, p < 0.001). Significant reduction in blood pressure measurement (4 mmHg, p = 0.029), reduction in waist- to- hip ratio and waist- circumference, decrease in blood glucose marker HbA1c (1 mmol/mol, p = 0.005) and increase in fasting glucose (0.1 mmol/L, p = 0.046) were also observed at the end of twelve weeks. Faecal microbiota composition showed an increase in the abundance of uncharacterised bacterial family. The authors concluded that these result were not sufficiently significant to draw conclusions and further studies with larger sample sizes are required to confirm the outcomes of this study.
Abstract
Kiwifruit are a nutrient dense food and an excellent source of vitamin C. Supplementation of the diet with kiwifruit enhances plasma vitamin C status and epidemiological studies have shown an association between vitamin C status and reduced insulin resistance and improved blood glucose control. In vitro experiments suggest that eating kiwifruit might induce changes to microbiota composition and function; however, human studies to confirm these findings are lacking. The aim of this study was to investigate the effect of consuming two SunGold kiwifruit per day over 12 weeks on vitamin C status, clinical and anthropometric measures and faecal microbiota composition in people with prediabetes. This pilot intervention trial compared baseline measurements with those following the intervention. Participants completed a physical activity questionnaire and a three-day estimated food diary at baseline and on completion of the trial. Venous blood samples were collected at each study visit (baseline, 6, 12 weeks) for determination of glycaemic indices, plasma vitamin C concentrations, hormones, lipid profiles and high-sensitivity C-reactive protein. Participants provided a faecal sample at each study visit. DNA was extracted from the faecal samples and a region of the 16S ribosomal RNA gene was amplified and sequenced to determine faecal microbiota composition. When week 12 measures were compared to baseline, results showed a significant increase in plasma vitamin C (14 µmol/L, p < 0.001). There was a significant reduction in both diastolic (4 mmHg, p = 0.029) and systolic (6 mmHg, p = 0.003) blood pressure and a significant reduction in waist circumference (3.1 cm, p = 0.001) and waist-to-hip ratio (0.01, p = 0.032). Results also showed a decrease in HbA1c (1 mmol/mol, p = 0.005) and an increase in fasting glucose (0.1 mmol/L, p = 0.046), however, these changes were small and were not clinically significant. Analysis of faecal microbiota composition showed an increase in the relative abundance of as yet uncultivated and therefore uncharacterised members of the bacterial family Coriobacteriaceae. Novel bacteriological investigations of Coriobacteriaceae are required to explain their functional relationship to kiwifruit polysaccharides and polyphenols.
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Can Reduced Intake Associated with Downsizing a High Energy Dense Meal Item be Offset by Increased Vegetable Variety in 3⁻5-year-old Children?
Carstairs, SA, Caton, SJ, Blundell-Birtill, P, Rolls, BJ, Hetherington, MM, Cecil, JE
Nutrients. 2018;10(12)
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Large proportions of energy dense foods tend to lead to over-consumption. However, offering smaller portions of energy-dense foods may lead to compensatory consumption of other foods. The aim of this study was to investigate the effects of reducing portion sizes of energy-dense foods, whilst increasing the variety of vegetables offered to pre-school children. The study was an experimental design were 51 participants – 3 to 5-year old pre-school children - were offered a lunch meal which was either a standard (100%) or downsized (60%) portion of a high-energy dense food over a period of 8 weeks. The results showed a significant reduction in intake of the high energy dense meal item and total meal intake in pre-school children. Offering a variety of vegetables as low energy dense sides within the meal increased vegetable intake compared to offering a single vegetable. Authors conclude that downsizing the portion of the high energy dense component of a lunch-time meal can be used as an effective strategy to reduce high energy dense food intake without a compensatory change in intake of other foods in pre-school aged children.
Abstract
Large portions of energy dense foods promote overconsumption but offering small portions might lead to compensatory intake of other foods. Offering a variety of vegetables could help promote vegetable intake and offset the effect of reducing the portion size (PS) of a high energy dense (HED) food. Therefore, we tested the effect on intake of reducing the PS of a HED unit lunch item while varying the variety of the accompanying low energy dense (LED) vegetables. In a within-subjects design, 43 3⁻5-year-old pre-schoolers were served a lunch meal in their nursery on 8 occasions. Children were served a standard (100%) or downsized (60%) portion of a HED sandwich with a side of LED vegetables offered as a single (carrot, cherry tomato, cucumber) or variety (all 3 types) item. Reducing the PS of a HED sandwich reduced sandwich (g) (p < 0.001) and total meal intake (kcal) consumption (p = 0.001) without an increased intake of other foods in the meal (LED vegetables (p = 0.169); dessert (p = 0.835)). Offering a variety of vegetables, compared with a single vegetable, increased vegetable intake (g) (p = 0.003) across PS conditions. Downsizing and variety were effective strategies individually for altering pre-schoolers' intakes of HED and LED meal items, however, using variety to offset HED downsizing was not supported in the present study.
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How and why weight stigma drives the obesity 'epidemic' and harms health.
Tomiyama, AJ, Carr, D, Granberg, EM, Major, B, Robinson, E, Sutin, AR, Brewis, A
BMC medicine. 2018;16(1):123
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Weight stigma is defined as the social rejection and devaluation that accrues to those who do not comply with prevailing social norms of adequate body weight and shape. In this opinion-based study, authors discuss that: • Latest literature indicates that weight stigma can trigger physiological and behavioural changes linked to poor metabolic health and increased weight gain. • Healthcare is a setting in which weight stigma is particularly pervasive, with significant consequences for the health of higher-weight patients. This stigma has direct and observable consequences for the quality and nature of services provided to those with obesity. • Stigma may be an unintended consequence of anti-obesity efforts, undermining their intended effect. Moreover, focusing solely on obesity treatment runs the risk of missing other diagnoses. • The science of weight stigma crystallizes a key point for future success – to tackle the obesity ‘epidemic’ we must tackle the parallel epidemic of weight stigma. • Public service messages are needed to educate people about the stigma, discrimination, and challenges facing higher-weight individuals. Authors conclude that to advance as an equal society, healthcare providers should lead the way for weight stigma eradication.
Abstract
BACKGROUND In an era when obesity prevalence is high throughout much of the world, there is a correspondingly pervasive and strong culture of weight stigma. For example, representative studies show that some forms of weight discrimination are more prevalent even than discrimination based on race or ethnicity. DISCUSSION In this Opinion article, we review compelling evidence that weight stigma is harmful to health, over and above objective body mass index. Weight stigma is prospectively related to heightened mortality and other chronic diseases and conditions. Most ironically, it actually begets heightened risk of obesity through multiple obesogenic pathways. Weight stigma is particularly prevalent and detrimental in healthcare settings, with documented high levels of 'anti-fat' bias in healthcare providers, patients with obesity receiving poorer care and having worse outcomes, and medical students with obesity reporting high levels of alcohol and substance use to cope with internalized weight stigma. In terms of solutions, the most effective and ethical approaches should be aimed at changing the behaviors and attitudes of those who stigmatize, rather than towards the targets of weight stigma. Medical training must address weight bias, training healthcare professionals about how it is perpetuated and on its potentially harmful effects on their patients. CONCLUSION Weight stigma is likely to drive weight gain and poor health and thus should be eradicated. This effort can begin by training compassionate and knowledgeable healthcare providers who will deliver better care and ultimately lessen the negative effects of weight stigma.
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Predictors of weight stigma experienced by middle-older aged, general-practice patients with obesity in disadvantaged areas of Australia: a cross-sectional study.
Spooner, C, Jayasinghe, UW, Faruqi, N, Stocks, N, Harris, MF
BMC public health. 2018;18(1):640
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People in higher categories of obesity are at substantially increased health risk because mortality increases sharply as body mass index rises above 30. In addition to physical health risks, people with obesity commonly experience weight-related stigma. The aim of this study was to identify predictors of perceived weight stigma among patients with obesity attending general practices in socioeconomically disadvantaged urban areas of Australia. This is a cross-sectional study for which data from telephone interviews with patients with obesity were used. Patients were recruited from 17 general practices in socioeconomically disadvantaged areas of Sydney and Adelaide. Results indicate that one-third of the sample had experienced direct forms of weight discrimination in the week before being interviewed. Furthermore, weight discrimination was more likely to be experienced by patients in higher obesity categories, who were not employed, who spoke a language other than English at home and who had lower scores on the Health Literacy Questionnaire domain (that measures the ability to actively engage with healthcare providers). Authors conclude that weight stigma may compound other forms of social disadvantage. Thus, strategies are needed to address weight stigma at the individual, system and population levels and to educate primary care providers to be more alert to the needs of their patients with obesity.
Abstract
BACKGROUND Rates of obesity have increased globally and weight stigma is commonly experienced by people with obesity. Feeling stigmatised because of one's weight can be a barrier to healthy eating, physical activity and to seeking help for weight management. The aim of this study was to identify predictors of perceived weight among middle-older aged patients with obesity attending general practices in socioeconomically disadvantaged urban areas of Australia. METHODS As part of a randomised clinical trial in Australia, telephone interviews were conducted with 120 patients from 17 general practices in socioeconomically disadvantaged of Sydney and Adelaide. Patients were aged 40-70 years with a BMI ≥ 30 kg/m2. The interviews included questions relating to socio-demographic variables (e.g. gender, language spoken at home), experiences of weight-related discrimination, and the Health Literacy Questionnaire (HLQ). Multi-level logistic regression data analysis was undertaken to examine predictors of recent experiences of weight-related discrimination ("weight stigma"). RESULTS The multi-level model showed that weight stigma was positively associated with obesity category 2 (BMI = 35 to < 40; OR 4.47 (95% CI 1.03 to 19.40)) and obesity category 3 (BMI = ≥ 40; OR 27.06 (95% CI 4.85 to 150.95)), not being employed (OR 7.70 (95% CI 2.17 to 27.25)), non-English speaking backgrounds (OR 5.74 (95% CI 1.35 to 24.45)) and negatively associated with the HLQ domain: ability to actively engage with healthcare providers (OR 0.12 (95% CI 0.05 to 0.28)). There was no association between weight stigma and gender, age, education or the other HLQ domains examined. CONCLUSIONS Weight stigma disproportionately affected the patients with obesity most in need of support to manage their weight: those with more severe obesity, from non-English speaking backgrounds and who were not in employment. Additionally, those who had experienced weight stigma were less able to actively engage with healthcare providers further compounding their disadvantage. This suggests the need for a more proactive approach to identify weight stigma by healthcare providers. Addressing weight stigma at the individual, system and population levels is recommended. TRIAL REGISTRATION The trial was registered with the Australian Clinical Trials Registry ACTRN126400102162 .
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Swimming pool exposure is associated with autonomic changes and increased airway reactivity to a beta-2 agonist in school aged children: A cross-sectional survey.
Cavaleiro Rufo, J, Paciência, I, Silva, D, Martins, C, Madureira, J, Oliveira Fernandes, E, Padrão, P, Moreira, P, Delgado, L, Moreira, A
PloS one. 2018;13(3):e0193848
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Studies have shown an association between swimming in chemically-treated pools and a higher risk of asthma in children, although the mechanism is not fully understood. This study aimed to investigate how swimming pool attendance influences lung and nervous system function in school-aged children. Around 800 children were classified as current swimmers (CS), past swimmers (PS) or non-swimmers (NS). The children underwent several tests to determine their lung function and allergic response to common allergens. Parasympathetic nervous system function was tested by measuring the speed at which their pupils constricted in response to light. The current swimmers group had significantly lower pupil constriction speeds compared to PS and NS, suggesting a poorer functioning of the autonomic nervous system, possibly due to inflammation resulting from swimming pool chemical exposure. CS experienced greater constriction of the airways compared to NS. A non-significant trend for a higher risk of asthma, atopic eczema and rhinitis, was observed in swimmers. The authors concluded that swimming pool attendance appears to be associated with autonomic nervous system changes and increased baseline airway smooth muscle constriction even in children without asthma.
Abstract
BACKGROUND Endurance swimming exercises coupled to disinfection by-products exposure has been associated with increased airways dysfunction and neurogenic inflammation in elite swimmers. However, the impact of swimming pool exposure at a recreational level on autonomic activity has never been explored. Therefore, this study aimed to investigate how swimming pool attendance is influencing lung and autonomic function in school-aged children. METHODS A total of 858 children enrolled a cross sectional survey. Spirometry and airway reversibility to beta-2 agonist, skin-prick-tests and exhaled nitric oxide measurements were performed. Pupillometry was used to evaluate autonomic nervous function. Children were classified as current swimmers (CS), past swimmers (PS) and non-swimmers (NS), according to the amount of swimming practice. RESULTS Current swimmers group had significantly lower maximum and average pupil constriction velocities when compared to both PS and NS groups (3.8 and 5.1 vs 3.9 and 5.3 vs 4.0 and 5.4 mm/s, p = 0.03 and p = 0.01, respectively). Moreover, affinity to the beta-2 agonist and levels of exhaled nitric oxide were significantly higher in CS when compared to NS (70 vs 60 mL and 12 vs 10 ppb, p<0.01 and p = 0.03, respectively). A non-significant trend for a higher risk of asthma, atopic eczema and allergic rhinitis was found with more years of swimming practice, particularly in atopic individuals (β = 1.12, 1.40 and 1.31, respectively). After case-case analysis, it was possible to observe that results were not influenced by the inclusion of individuals with asthma. CONCLUSIONS Concluding, swimming pool attendance appears to be associated with autonomic changes and increased baseline airway smooth muscle constriction even in children without asthma.
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Nutritional labelling for healthier food or non-alcoholic drink purchasing and consumption.
Crockett, RA, King, SE, Marteau, TM, Prevost, AT, Bignardi, G, Roberts, NW, Stubbs, B, Hollands, GJ, Jebb, SA
The Cochrane database of systematic reviews. 2018;2:CD009315
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Poor quality diets are a threat to health internationally and a challenge to health services. Implementing methods to change people's choices is difficult; even those who start making healthier choices often find it hard to maintain long-term. There is recognition that our environment has a powerful influence over our food choices and altering this may stimulate behavioural change. Nutritional labels provide information about the nutritional content of a food or drink. The type of information provided varies e.g. what nutrients they describe (e.g. macronutrients like fat or energy content) and the form also varies e.g. as a single number, as a proportion of a guideline for daily consumption, or with colours indicative of relative healthiness. Nutritional labelling has been rolled-out in many forms, across many countries but there is currently no consensus as to the best way of applying this information to products to stimulate healthier food choices. This review explored whether nutritional labels persuade consumers to buy alternative types of food and included 28 articles. Findings from these 28 articles suggest that nutritional labelling specially indicating energy content may cause people to opt to buy foods with a lower energy content in restaurants. This result (only based on 3 studies) suggests that nutritional labelling could be rolled-out on menus in restaurants, but high-quality research is required. Higher-quality research is also needed to explore the impact of nutritional labelling in shops and vending machines.
Abstract
BACKGROUND Nutritional labelling is advocated as a means to promote healthier food purchasing and consumption, including lower energy intake. Internationally, many different nutritional labelling schemes have been introduced. There is no consensus on whether such labelling is effective in promoting healthier behaviour. OBJECTIVES To assess the impact of nutritional labelling for food and non-alcoholic drinks on purchasing and consumption of healthier items. Our secondary objective was to explore possible effect moderators of nutritional labelling on purchasing and consumption. SEARCH METHODS We searched 13 electronic databases including CENTRAL, MEDLINE and Embase to 26 April 2017. We also handsearched references and citations and sought unpublished studies through websites and trials registries. SELECTION CRITERIA Eligible studies: were randomised or quasi-randomised controlled trials (RCTs/Q-RCTs), controlled before-and-after studies, or interrupted time series (ITS) studies; compared a labelled product (with information on nutrients or energy) with the same product without a nutritional label; assessed objectively measured purchasing or consumption of foods or non-alcoholic drinks in real-world or laboratory settings. DATA COLLECTION AND ANALYSIS Two authors independently selected studies for inclusion and extracted study data. We applied the Cochrane 'Risk of bias' tool and GRADE to assess the quality of evidence. We pooled studies that evaluated similar interventions and outcomes using a random-effects meta-analysis, and we synthesised data from other studies in a narrative summary. MAIN RESULTS We included 28 studies, comprising 17 RCTs, 5 Q-RCTs and 6 ITS studies. Most (21/28) took place in the USA, and 19 took place in university settings, 14 of which mainly involved university students or staff. Most (20/28) studies assessed the impact of labelling on menus or menu boards, or nutritional labelling placed on, or adjacent to, a range of foods or drinks from which participants could choose. Eight studies provided participants with only one labelled food or drink option (in which labelling was present on a container or packaging, adjacent to the food or on a display board) and measured the amount consumed. The most frequently assessed labelling type was energy (i.e. calorie) information (12/28).Eleven studies assessed the impact of nutritional labelling on purchasing food or drink options in real-world settings, including purchases from vending machines (one cluster-RCT), grocery stores (one ITS), or restaurants, cafeterias or coffee shops (three RCTs, one Q-RCT and five ITS). Findings on vending machines and grocery stores were not interpretable, and were rated as very low quality. A meta-analysis of the three RCTs, all of which assessed energy labelling on menus in restaurants, demonstrated a statistically significant reduction of 47 kcal in energy purchased (MD -46.72 kcal, 95% CI -78.35, -15.10, N = 1877). Assuming an average meal of 600 kcal, energy labelling on menus would reduce energy purchased per meal by 7.8% (95% CI 2.5% to 13.1%). The quality of the evidence for these three studies was rated as low, so our confidence in the effect estimate is limited and may change with further studies. Of the remaining six studies, only two (both ITS studies involving energy labels on menus or menus boards in a coffee shop or cafeteria) were at low risk of bias, and their results support the meta-analysis. The results of the other four studies which were conducted in a restaurant, cafeterias (2 studies) or a coffee shop, were not clearly reported and were at high risk of bias.Seventeen studies assessed the impact of nutritional labels on consumption in artificial settings or scenarios (henceforth referred to as laboratory studies or settings). Of these, eight (all RCTs) assessed the effect of labels on menus or placed on a range of food options. A meta-analysis of these studies did not conclusively demonstrate a reduction in energy consumed during a meal (MD -50 kcal, 95% CI -104.41, 3.88, N = 1705). We rated the quality of the evidence as low, so our confidence in the effect estimate is limited and may change with further studies.Six laboratory studies (four RCTs and two Q-RCTs) assessed the impact of labelling a single food or drink option (such as chocolate, pasta or soft drinks) on energy consumed during a snack or meal. A meta-analysis of these studies did not demonstrate a statistically significant difference in energy (kcal) consumed (SMD 0.05, 95% CI -0.17 to 0.27, N = 732). However, the confidence intervals were wide, suggesting uncertainty in the true effect size. We rated the quality of the evidence as low, so our confidence in the effect estimate is limited and may change with further studies.There was no evidence that nutritional labelling had the unintended harm of increasing energy purchased or consumed. Indirect evidence came from five laboratory studies that involved mislabelling single nutrient content (i.e. placing low energy or low fat labels on high-energy foods) during a snack or meal. A meta-analysis of these studies did not demonstrate a statistically significant increase in energy (kcal) consumed (SMD 0.19, 95% CI -0.14to 0.51, N = 718). The effect was small and the confidence intervals wide, suggesting uncertainty in the true effect size. We rated the quality of the evidence from these studies as very low, providing very little confidence in the effect estimate. AUTHORS' CONCLUSIONS Findings from a small body of low-quality evidence suggest that nutritional labelling comprising energy information on menus may reduce energy purchased in restaurants. The evidence assessing the impact on consumption of energy information on menus or on a range of food options in laboratory settings suggests a similar effect to that observed for purchasing, although the evidence is less definite and also of low quality.Accordingly, and in the absence of observed harms, we tentatively suggest that nutritional labelling on menus in restaurants could be used as part of a wider set of measures to tackle obesity. Additional high-quality research in real-world settings is needed to enable more certain conclusions.Further high-quality research is also needed to address the dearth of evidence from grocery stores and vending machines and to assess potential moderators of the intervention effect, including socioeconomic status.