Christopher Penfold

Does low-energy sweetener consumption affect energy intake and body weight? A systematic review, including meta- analyses, of the evidence from human and animal studies

By reducing energy density, low-energy sweeteners (LES) might be expected to reduce energy intake (EI) and body weight (BW). To assess the totality of the evidence testing the null hypothesis that LES exposure (versus sugars or unsweetened alternatives) has no effect on EI or BW, we conducted a systematic review of relevant studies in animals and humans consuming LES with ad libitum access to food energy. In 62 of 90 animal studies exposure to LES did not affect or decreased BW. Of 28 reporting increased BW, 19 compared LES with glucose exposure using a specific ‘learning’ paradigm. Twelve prospective cohort studies in humans reported inconsistent associations between LES use and body mass index (−0.002 kg m−2 per year, 95% confidence interval (CI) −0.009 to 0.005). Meta-analysis of short-term randomized controlled trials (129 comparisons) showed reduced total EI for LES versus sugar-sweetened food or beverage consumption before an ad libitum meal (−94 kcal, 95% CI −122 to −66), with no difference versus water (−2 kcal, 95% CI −30 to 26). This was consistent with EI results from sustained intervention randomized controlled trials (10 comparisons). Meta-analysis of sustained intervention randomized controlled trials (4 weeks to 40 months) showed that consumption of LES versus sugar led to relatively reduced BW (nine comparisons; −1.35 kg, 95% CI –2.28 to −0.42), and a similar relative reduction in BW versus water (three comparisons; −1.24 kg, 95% CI –2.22 to −0.26). Most animal studies did not mimic LES consumption by humans, and reverse causation may influence the results of prospective cohort studies. The preponderance of evidence from all human randomized controlled trials indicates that LES do not increase EI or BW, whether compared with caloric or non-caloric (for example, water) control conditions. Overall, the balance of evidence indicates that use of LES in place of sugar, in children and adults, leads to reduced EI and BW, and possibly also when compared with water.

Randomized clinical trial of postoperative chewing gum versus standard care after colorectal resection.

Chewing gum may stimulate gastrointestinal motility, with beneficial effects on postoperative ileus suggested in small studies. The primary aim of this trial was to determine whether chewing gum reduces length of hospital stay (LOS) after colorectal resection. Secondary aims included examining bowel habit symptoms, complications and healthcare costs.

Physical activity, alcohol consumption, BMI and smoking status before and after prostate cancer diagnosis in the ProtecT trial: Opportunities for lifestyle modification

Associations between certain lifestyle characteristics and prostate cancer risk have been reported, and continuation post‐diagnosis can adversely affect prognosis. We explored whether men make spontaneous changes to their physical activity and alcohol intake, body mass index (BMI) and smoking status, following a diagnosis of localised prostate cancer. A detailed diet, health and lifestyle questionnaire was completed by 511 participants within the Prostate Testing for Cancer and Treatment (ProtecT) randomised controlled trial, both before and 9 months after a diagnosis of prostate cancer. Of 177 men who were insufficiently active before their diagnosis (median 0 activity units/week; IQR 0–9), 40.7% had increased their activity by a median of 22 U week−1 (IQR 15–35) 9 months later, and there was weak evidence that men were more active after diagnosis than before (p = 0.07). Men categorised as “working” occupational social class and who were insufficiently active before diagnosis were 2.03 (95%, CI = 1.03–3.99, p = 0.04) times more likely to have increased their physical activity levels compared to men classified as “managerial or professional.” Similarly, men who were insufficiently active pre‐diagnosis and with T‐stage 2 compared with T‐stage 1 prostate cancer were 2.47 (95%, CI = 1.29–4.71, p = 0.006) times more likely to be sufficiently active post‐diagnosis. Following diagnosis, there was an overall reduction in alcohol intake (p = 0.03) and the proportion of current smokers (p = 0.09), but no overall change in BMI. We conclude that some men spontaneously change certain lifestyle behaviours on receiving a diagnosis of prostate cancer. For many men, however, additional support through lifestyle interventions is probably required to facilitate and maintain these changes.

Folic acid in pregnancy and mortality from cancer and cardiovascular disease: further follow-up of the Aberdeen folic acid supplementation trial

Background Supplemental periconceptional folic acid is recommended to reduce the risk of fetal neural tube defects. A previous report indicated an elevated risk of breast cancer and all cancer deaths in later life among women randomised by alternate allocation to high-dose (5 mg/day) folic acid in pregnancy compared with placebo; however, findings were based on small numbers of cases. Our aim was to extend the previous analysis by including data from an additional 10 years of follow-up. Methods Records of participants in a large (n=2928) trial of folate supplementation (5 or 0.2 mg folic acid, or placebo) in pregnancy in the 1960s were linked to central registries in Scotland. Unadjusted and adjusted HRs were calculated for all-cause, cardiovascular, all cancer and breast cancer mortality, and all cancer and breast cancer morbidity. Analyses were done using (1) data from the time of the previous linkage (2002) to March 2013; and (2) data from 1980 to March 2013. Results There was no evidence to suggest an excess risk of morbidity or mortality in either supplementation group compared with placebo for 2002–2013 and no associations were seen for the full time period (1980–2013). Conclusions Findings from this extended follow-up do not support our previous observation of an elevated risk of mortality from breast cancer or all cancers in later life among women who had taken 5 mg folic acid/day during pregnancy. Furthermore, there were no associations with risk of mortality from all-causes, all cancers or cardiovascular disease.

An overview of systematic reviews of complementary and alternative therapies for fibromyalgia using both AMSTAR and ROBIS as quality assessment tools

BackgroundFibromyalgia (FM) is a chronic, debilitating pain disorder. Dissatisfaction with conventional medicine can lead people with FM to turn to complementary and alternative medicine (CAM). Two previous overviews of systematic reviews of CAM for FM have been published, but they did not assessed for risk of bias in the review process.MethodsFive databases Medline, Embase, AMED (via OVID), Web of Science and Central were searched from their inception to December 2015. Reference lists were hand-searched. We had two aims: the first was to provide an up-to-date and rigorously conducted synthesis of systematic reviews of CAM literature on FM; the second was to evaluate the quality of the available systematic review evidence using two different tools: AMSTAR (Shea et al. BMC Med Res Methodol 15; 7:10, 2007) and a more recently developed tool ROBIS (Whiting et al. J Clin Epidemiol 69:225-34, 2016) specifically designed to assess risk of bias in systematic reviews. Any review that assessed one of eight CAM therapies for participants diagnosed with FM was considered. The individual studies had to be randomised controlled trials where the intervention was compared to placebo, treatment as usual or waitlist controls to be included. The primary outcome measure was pain, and the secondary outcome measure was adverse events.ResultsWe identified 15 reviews that met inclusion criteria. There was low-quality evidence that acupuncture improves pain compared to no treatment or standard treatment, but good evidence that it is no better than sham acupuncture. The evidence for homoeopathy, spinal manipulation and herbal medicine was limited.ConclusionsOverall, five reviews scored 6 or above using the AMSTAR scale and the inter-rater agreement was good (83.6%), whereas seven reviews achieved a low risk of bias rating using ROBIS and the inter-rater agreement was fair (60.0%). No firm conclusions were drawn for efficacy of either spinal manipulation or homoeopathy for FM. There is limited evidence for topical Capsicum, but further research is required. There is some evidence to support the effectiveness of acupuncture for FM, but further high-quality trials are needed to investigate its benefits, harms and mechanisms of action, compared with no or standard treatment.Systematic review registrationPROSPERO CRD42016035846.

Recommendation to test limonene hydroperoxides 0·3% and linalool hydroperoxides 1·0% in the British baseline patch test series

There is a significant rate of sensitization worldwide to the oxidized fragrance terpenes limonene and linalool. Patch testing to oxidized terpenes is not routinely carried out; the ideal patch test concentration is unknown.

Tobacco and alcohol cessation or reduction interventions in people with oral dysplasia and head and neck cancer: systematic review protocol

BackgroundHead and neck cancers include malignancies of the mouth, larynx and oropharynx. Tobacco use and alcohol consumption are associated with increased risks of developing and dying from head and neck cancer. The aim of this review is to examine the effectiveness of smoking and alcohol cessation interventions on disease-related outcomes, quality of life and behavioural change in adults with head and neck cancer and oral dysplasia.MethodsThe Cochrane library, CINAHL, Embase, MEDLINE, PsycINFO and Web of Science databases will be searched for randomised controlled trials investigating the effects of smoking or alcohol interventions on patients with either head and neck cancer or oral dysplasia. The primary outcomes are disease-free survival and, for participants with oral dysplasia, malignant transformation to cancer. Secondary outcomes are disease recurrence and progression, quality of life and behavioural change. The quality of included studies will be assessed using the ‘Cochrane Collaborations tool for assessing risk of bias’. A qualitative synthesis of the results will be reported, and a meta-analysis of the outcome data conducted, where appropriate.DiscussionThis systematic review will identify the extent of the current research on smoking and alcohol cessation interventions in patients with head and neck cancer and oral epithelial dysplasia. The findings have the potential to inform which interventions have been successful and how future behavioural change interventions should be conducted within these populations.Systematic review registrationPROSPERO CRD42016038237

The Effectiveness of Green Tea or Green Tea Extract on Insulin Resistance and Glycemic Control in Type 2 Diabetes Mellitus: A Meta-Analysis

Green tea or green tea extract (GT/GTE) has been demonstrated to reduce insulin resistance and improve glycemic control. However, evidence for this health beneficial effect is inconsistent. This systematic review evaluated the effect of GT/GTE on insulin resistance and glycemic control in people with pre-diabetes/type 2 diabetes mellitus (T2DM). Ovid MEDLINE, Embase, AMED, Web of Science, and the Cochrane Library were searched up to April 2017 for randomised controlled trials of participants with pre-diabetes or T2DM, where the intervention was GT/GTE. Meta-analysis was performed to assess the standardised mean difference (SMD) in biomarkers of insulin resistance and glycemic control between GT/GTE and placebo groups. Six studies (n=382) were pooled into random-effects meta-analysis. Overall, no differences were found between GT/GTE and the placebo for glycosylated hemoglobin (HbA1c: SMD, −0.32; 95% confidence interval [CI], −0.86 to 0.23), homeostatic model assessment for insulin resistance (HOMA-IR: SMD, 0.10; 95% CI, −0.17 to 0.38), fasting insulin (SMD, −0.25; 95% CI, −0.64 to 0.15), and fasting glucose (SMD, −0.10; 95% CI, −0.50 to 0.30). No evidence support the consumption of GT/GTE could reduce the levels of HbA1c, HOMA-IR, fasting insulin, or fasting glucose in people with pre-diabetes/T2DM. However, the studies included were small and of varying quality.

Systematic review evaluating randomized controlled trials of smoking and alcohol cessation interventions in people with head and neck cancer and oral dysplasia.

Smoking and alcohol increase the risk of head and neck cancer and affect treatment outcomes. Interventions modifying these behaviors may improve posttreatment outcomes and survival. We systematically reviewed evidence of the effectiveness of smoking/alcohol interventions in head and neck cancer and oral dysplasia.

Change in alcohol and tobacco consumption after a diagnosis of head and neck cancer: Findings from head and neck 5000

Abstract Background Tobacco and alcohol consumption are risk factors for developing head and neck cancer, and continuation postdiagnosis can adversely affect prognosis. We explored changes to these behaviors after a head and neck cancer diagnosis. Methods Demographic and clinical data were collected from 973 people newly diagnosed with oral cavity, oropharyngeal, or laryngeal cancer. Tobacco and alcohol consumption were additionally collected 4 and 12 months later. Results The prevalence of high alcohol consumption reduced from 54.3% at diagnosis to 41.4% at 12 months, and smoking reduced from 21.0% to 11.7%. Changes in behavior were dynamic, for example, 44% of smokers at 12 months were not smoking at diagnosis or 4 months. Several factors were associated with alcohol consumption, whereas only tumor site and comorbidities were associated with smoking. Conclusion A diagnosis of head and neck cancer can result in important changes in alcohol consumption and smoking prevalence. However, these changes are dynamic in the first year after diagnosis.