Our external research programme
WSRO is dedicated to improving understanding of the role that dietary sugars play in human nutrition and health. Committed to transparent engagement with researchers and external partners, we support a small programme of peer-reviewed transparent research aimed at addressing knowledge gaps within the global scientific literature on sugars and health. We commission and fund systematic reviews and research studies, through the provision of unrestricted research grants. These research projects are undertaken by scientists in established academic institutions across the globe and published Open Access in peer-reviewed scientific journals.
Scientific integrity and practice
We adhere to a set of Operating Principles to ensure integrity and transparency in our activities. These are based on:
Peer review policy for internal publications
WSRO is committed to the principles of scientific peer review even for internal scientific documents (briefings, factsheets etc.). WSRO follows scientific review procedures to ensure that scientific documents disseminated by the organisation meet the same scientific quality standards as those published in scientific journals. Reviewers cannot have prior direct involvement in the authorship of the document undergoing review. Reviewers are acknowledged in the document for their expert contribution.
Examples of past research projects supported by WSRO
Research projects supported by the World Sugar Research Organisation are independently peer reviewed according to the review process of the scientific journal in which they are published. It is a requirement of research projects in receipt of financial support from WSRO that they are published Open Access, in peer-reviewed scientific journals. Researchers receiving financial support from WSRO are contractually required to clearly declare this upon the scientific publications supported.
Abstract
Understanding the relationship between the intake of sugars and diet quality can inform public health recommendations. This systematic review synthesized recent literature on associations between sugar intake and diet quality in generally healthy populations aged 2 years or older. We searched databases from 2010 to 2022 for studies of any design examining associations between quantified sugar intake in the daily diet and dietary indexes (DIs) or micronutrient intakes. Different sugar types and diet quality measures were analyzed separately. We converted DI results to Pearson's r correlations and grouped indexes with or without a free or added sugar component to facilitate cross-study comparisons. Meta-analysis was deemed inappropriate. From 13,869 screened records, we included 27 cross-sectional studies. NUQUEST risk of bias ratings were neutral (n = 18 studies) or poor (n = 9), and strength of evidence by the GRADE approach was very low due to study design. Most studies reported negative associations for added and free sugars with diet quality indexes (r ranging from -0.13 to -0.42) and nutrients of public health concern (fiber, vitamin D, calcium, potassium), while associations with total sugars were mixed. Due to cross-sectional study designs, the clinical relevance of these findings is unclear. Prospective studies are needed to minimize confounding and inform causal relationships.
Abstract
Currently, there is considerable emphasis on the relationship between dietary sugar consumption and various health outcomes, with some countries and regions implementing national sugar reduction campaigns. This has resulted in significant efforts to quantify dietary sugar intakes, to agree on terms to describe dietary sugars and to establish associated recommendations. However, this information is infrequently collated on a global basis and in a regularised manner. The present review provides context regarding sugar definitions and recommendations. It provides a global review of the available data regarding dietary sugar intake, considering forms such as total, free and added sugars. A comprehensive breakdown of intakes is provided by age group, country and sugar form. This analysis shows that free sugar intakes as a percentage of total energy (%E) are the highest for children and adolescents (12-14%E) and the lowest for older adults (8%E). This trend across lifecycle stages has also been observed for added sugars. The available data also suggest that, while some reductions in sugar intake are observed in a few individual studies, overall intakes of free/added sugars remain above recommendations. However, any wider conclusions are hampered by a lack of detailed high-quality data on sugar intake, especially in developing countries. Furthermore, there is a need for harmonisation of terms describing sugars (ideally driven by public health objectives) and for collaborative efforts to ensure that the most up-to-date food composition data are used to underpin recommendations and any estimates of intake or modelling scenarios.
Abstract
There are well known phenotypic differences in sweet-liking across individuals, but it remains unknown whether these are related to broader underlying differences in interoceptive abilities (abilities to sense the internal state of the body). Here, healthy women (N = 64) classified as sweet likers (SLs) or sweet dislikers (SDs) completed a bimodal interoception protocol. A heartbeat tracking and a heartbeat discrimination task determined cardiac interoception; both were accompanied by confidence ratings. A water load task, where participants consumed water to satiation and then to maximum fullness was used to assess gastric interoceptive abilities. Motivational state, psychometric characteristics and eating behaviour were also assessed. SLs performed significantly better than SDs on both heartbeat tasks, independently of impulsivity, anxiety, depression, and alexithymia. No differences in metacognitive awareness and subjective interoceptive measures were found. With gastric interoception, SLs were more sensitive to stomach distention, and they ingested less water than SDs to reach satiety when accounting for stomach capacity. SLs also scored higher on mindful and intuitive eating scales and on emotional eating particularly in response to negative stimuli; emotional overeating was fully mediated via interoceptive performance. Overall, our data suggest the SL phenotype may reflect enhanced responsiveness to internal cues more broadly.
Abstract
Taste hedonics drive food choices, and food choices affect weight maintenance. Despite this, the idea that hyper-palatability of sweet foods is linked to obesity development has been controversial for decades. Here, we investigate whether interpersonal differences in sweet-liking are related to body composition. Healthy adults aged 18–34 years from the UK (n = 148) and the US (n = 126) completed laboratory-based sensory tests (sucrose taste tests) and anthropometric measures (body mass index; BMI, body fat; fat-free mass; FFM, waist/hips circumferences). Habitual beverage intake and lifestyle and behavioural characteristics were also assessed. Using hierarchical cluster analysis, we classified participants into three phenotypes: sweet liker (SL), sweet disliker (SD), and inverted-U (liking for moderate sweetness). Being a SD was linked to higher body fat among those younger than 21 years old, while in the older group, SLs had the highest BMI and FFM; age groups reflected different levels of exposure to the obesogenic environment. FFM emerged as a better predictor of sweet-liking than BMI and body fat. In the older group, sweetened beverage intake partially explained the phenotype–anthropometry associations. Collectively, our findings implicate underlying energy needs as an explanation for the variation in sweet-liking; the moderating roles of age and obesogenic environment require additional consideration.
Abstract
Objective:
Debate continues regarding the influence of dietary fats and sugars on the risk of developing metabolic diseases, including insulin resistance and nonalcoholic fatty liver disease (NAFLD). We investigated the effect of two eucaloric diets, one enriched with saturated fat (SFA) and the other enriched with free sugars (SUGAR), on intrahepatic triacylglycerol (IHTAG) content, hepatic de novo lipogenesis (DNL), and whole-body postprandial metabolism in overweight males.
Research design and methods:
Sixteen overweight males were randomized to consume the SFA or SUGAR diet for 4 weeks before consuming the alternate diet after a 7-week washout period. The metabolic effects of the respective diets on IHTAG content, hepatic DNL, and whole-body metabolism were investigated using imaging techniques and metabolic substrates labeled with stable-isotope tracers.
Results:
Consumption of the SFA diet significantly increased IHTAG by mean ± SEM 39.0 ± 10.0%, while after the SUGAR diet IHTAG was virtually unchanged. Consumption of the SFA diet induced an exaggerated postprandial glucose and insulin response to a standardized test meal compared with SUGAR. Although whole-body fat oxidation, lipolysis, and DNL were similar following the two diets, consumption of the SUGAR diet resulted in significant (P < 0.05) decreases in plasma total, HDL, and non-HDL cholesterol and fasting β-hydroxybutyrate plasma concentrations.
Conclusions:
Consumption of an SFA diet had a potent effect, increasing IHTAG together with exaggerating postprandial glycemia. The SUGAR diet did not influence IHTAG and induced minor metabolic changes. Our findings indicate that a diet enriched in SFA is more harmful to metabolic health than a diet enriched in free sugars.
Abstract
Background
Evidence mapping is an emerging tool used to systematically identify, organize, and summarize the quantity, distribution, and characteristics of published studies with the goal of identifying knowledge gaps and future research needs.
Objective
The aim of the study was to present an evidence-map database of all published studies that investigated dietary sugars and to select health outcomes for explicating research trends and gaps.
Methods
To update an evidence-map database previously published in 2013, we performed a literature search in MEDLINE to identify English-language, peer-reviewed human intervention and prospective cohort studies published from January 2013 to December 2016. Abstracts and full-text articles were dual screened on the basis of predefined eligibility criteria. We classified outcomes into 7 health outcome categories that are potentially affected by dietary sugar. Data from the updated evidence-map database were merged with those from the previous database for analysis and charting.
Results
There were 918 sugar and control intervention arms from a total of 298 intervention studies from 1966 to December 2016. A variety of sugar interventions were investigated across the included intervention studies, and it appears that the research interest across all outcome categories (cardiovascular disease risks, diabetes risks, body weight, body composition, appetite, dietary intake, and liver health–related outcomes) sharply increased from 2006. Bubble plots showed research gaps in long-term intervention studies and in intervention studies in patients with diabetes. In contrast, all 25 included cohort studies had long-term follow-up durations and much larger sample sizes than did intervention studies. None of the cohort studies evaluated dietary intake outcomes, and only one cohort study each examined appetite- and liver health–related outcomes.
Conclusions
The research trends and research gaps have not changed since 2013 when the original evidence-map database was updated. With continuous updating, evidence mapping can facilitate the process of knowledge translation and possibly reduce research waste.
Keywords: dietary sugars, fructose, sucrose, added sugars, evidence map, scoping review, research gaps
