Quality of systematic reviews of the Foods with Function Claims registered at the Consumer Affairs Agency Web site in Japan: a prospective systematic review

[Current Status and Issues on the Foods with Function Claims System in Japan: Evidence of Functionality of the Foods]

The purpose of this narrative review was to clarify the current status and issues of scientific evidence for functionality in the Foods with Function Claims system based on previous research. From the introduction of the system in April 2015 to January 1, 2023, there were 6606 notifications, of which 6297 (95.3) were systematic reviews (SRs) and 309 (4.7%) were clinical trials (CTs). SRs were identified the following problems: i) inadequate description based on the first version of PRISMA checklist, and ii) very low levels of quality assessment in the first version of AMSTAR checklist and AMSTAR 2. CT was reported to have the following problems: i) inconsistencies between the protocol and the content in the paper (non-compliance), ii) high risk of bias, and iii) not described based on the CONSORT 2010 checklist. Since SRs and randomized controlled trials (RCTs) often have low-quality notifications, it is necessary to correctly communicate this information to consumers in order to make appropriate purchasing decisions.

A Cross-Sectional Study Based on Forty Systematic Reviews of Foods with Function Claims (FFC) in Japan: Quality Assessment Using AMSTAR 2

BACKGROUND

The Foods with Function Claims (FFC) was introduced in Japan in April 2015 to make more products available that are labeled with health functions. The products' functionality of function claims must be explained by scientific evidence presented in systematic reviews (SRs), but the quality of recent SRs is unclear. This study assessed the quality of SRs in the FFC registered on the Consumer Affairs Agency (CAA) website in Japan.

METHODS

We searched the database from 1 April to 31 October 2022. Confidence in the methodological quality of each SR was evaluated by the AMSTAR 2 checklist.

RESULTS

Forty SRs were randomly extracted on the basis of the eligibility criteria and recruitment procedures. Overall confidence was rated as "high" (N = 0, 0%), "moderate" (N = 0, 0%), "low" (N = 2, 5%), or "critically low" (N = 38, 95%). The mean AMSTAR 2 score was 51.1% (SD 12.1%; range 19-73%). Among the 40 SRs, the number of critical domain deficiencies was 4 in 7.5% of SRs, 3 in 52.5% of SRs, 2 in 35% of SRs, and 1 in 5% of SRs. Registering the review's protocol and comprehensive search strategies were particularly common deficiencies. Additionally, the risk of bias (RoB) was insufficiently considered.

CONCLUSION

Overall, the methodological quality of the SRs based on the FFC, introduced eight years earlier, was very poor. This was especially true in the interpretation and discussion of critical domains, which had many deficiencies in terms of protocol registration, a comprehensive literature search strategy, and accounting for the RoB.

Optimizing the Relationship between Regulation and Innovation in Dietary Supplements: A Case Study of Food with Function Claims in Japan

Regulation has long been a counterpart of innovation in the health care industry, and recent cases have demonstrated that appropriately designed regulations can both coexist with and promote innovation. This study is the first study to explore how the regulatory environment affected the innovation process during the transition of the regulations for functional foods in Japan by examining quantitatively the impact of the foods with function claims (FFC) system on industry, companies, and products. Based on a dataset of Japanese dietary supplement manufacturing companies (n = 169) and their products (n = 731) in 2019, we found that companies that have newly entered the FFC system are smaller in scale than existing companies (p < 0.01, Wilcoxon rank sum test). We also found that companies with FFC products have larger revenue growth (p = 0.01). A multiple regression analysis revealed that FFC product sales increased with in-house clinical testing (coefficient: 26.8, p < 0.0001), diverse active ingredients (coefficient: 7.6, p < 0.001), and the claim of new functions (coefficient: 10.2, p < 0.05). These results suggested that the FFC system facilitated the market entry of small and mid-size enterprises and promoted the creation of high-value products through innovative company efforts.

Pharmaceutical Food Science: Search for Bio-Functional Molecules Obtained from Natural Resources to Prevent and Ameliorate Lifestyle Diseases

In this review, our resent pharmaceutical food science research for bio-functional molecules obtained from natural resources that contribute to i) suppression of postprandial blood glucose elevation and/or improvement of glucose tolerance and ii) reduction of visceral fat accumulation and improvement of lipid metabolism were summarized. Based on studies using MONOTORI science, salacinol (1), neokotalanol (4), and trans-tiliroside (20) have been approved or notified by the Consumer Affairs Agency in Japan as functional substances in food with health claims, Food for Specified Health Use and Food with Functional Claims.

Compliance of Clinical Trial Protocols for Foods with Function Claims (FFC) in Japan: Consistency between Clinical Trial Registrations and Published Reports

Background: A new type of foods with a health claims notification system, the Foods with Function Claims (FFC), was introduced in Japan in April 2015. This cross-sectional study sought to clarify compliance of clinical trial protocols reported as the scientific basis of efficacy in the FFC system. Methods: All articles based on clinical trials published on the Consumer Affairs Agency website from 1 July 2018 to 30 June 2021 were reviewed. Items assessed included first author characteristics (for-profit or academia), journal name, year published, journal impact factor in 2020, article language, name of clinical trial registration (CTR), and seven compliance items (Title: T, Participant: P, Intervention: I, Comparison: C, Outcome: O, Study design: S, and Institutional Review Board, IRB). Among studies that conducted CTR, consistency with these seven compliance items was evaluated. Results: Out of 136 studies that met all inclusion criteria, 103 (76%) performed CTR, and CTR was either not performed or not specified for 33 (24%). Compliance between the protocol and the text was high (≥96%) for items P and S, but considerably lower for items T, I, C, O, and IRB (52%, 15%, 13%, 69%, and 27%, respectively). Furthermore, 43% of protocols did not include functional ingredients or food names in items T or I. The total score was 3.7 ± 1.1 pts (out of 7). Conclusions: Some CTs had no protocol registration, and even registered protocols were suboptimal in transparency. In addition to selective reporting, a new problem identified was that the content of the intervention (test food) was intentionally concealed.

Multi-stakeholder perspectives on food labeling and health claims: Qualitative insights from South Africa

Globally, the role of food labels in reducing non-communicable disease remains a point of debate. A particular area of contention is the use of health claims, an approach currently under consideration in South Africa - a developing country with vast socio-economic disparity. In the present study, in-depth interviews were conducted with 49 diverse stakeholders, including consumers and professionals from the food industry and other occupations, who shared their views about the use of health claims in a developing country context. The qualitative approach and inclusion of multiple perspectives that had not been motivated by a single stakeholder group added a novel view. Themes identified based on inductive analysis included: (i) practical barriers to label use; (ii) contextual and personal variables influencing engagement with label information; (iii) messaging preferences (for positively worded claims, compared to more cautionary statements); (iv) stakeholder complexities - mainly related to responsibility and trust; and (v) ambassadors to change. Findings indicate that there are persistent barriers to label use, such as challenges related to literacy and legibility. Furthermore, the socio-economic circumstances prevalent in South Africa drive large volumes of food sales in informal markets where labels are often not present. Unresolved questions about the substantiation and enforcement of health claims, combined with no solution being apparent for reaching consumers in the informal market, would limit the benefits that could be associated with the implementation of health claims at this point in time.

A review of antidiabetic active thiosugar sulfoniums, salacinol and neokotalanol, from plants of the genus Salacia

During our studies characterizing functional substances from food resources for the prevention and treatment of lifestyle-related diseases, we isolated the active constituents, salacinol (1) and neokotalanol (4), and related thiosugar sulfoniums, from the roots and stems of the genus Salacia plants [Celastraceae (Hippocrateaceae)] such as Salacia reticulata Wight, S. oblonga Wall., and S. chinensis L., and observed their antidiabetic effects. These plant materials have been used traditionally in Ayurvedic medicine as a specific remedy at the early stage of diabetes, and have been extensively consumed in Japan, the United States, and other countries as a food supplement for the prevention of obesity and diabetes. Here, we review our studies on the antidiabetic effects of plants from the genus Salacia, from basic chemical and pharmacological research to their application and development as new functional food ingredients.

The International Scientific Association of Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of postbiotics

In 2019, the International Scientific Association for Probiotics and Prebiotics (ISAPP) convened a panel of experts specializing in nutrition, microbial physiology, gastroenterology, paediatrics, food science and microbiology to review the definition and scope of postbiotics. The term 'postbiotics' is increasingly found in the scientific literature and on commercial products, yet is inconsistently used and lacks a clear definition. The purpose of this panel was to consider the scientific, commercial and regulatory parameters encompassing this emerging term, propose a useful definition and thereby establish a foundation for future developments. The panel defined a postbiotic as a "preparation of inanimate microorganisms and/or their components that confers a health benefit on the host". Effective postbiotics must contain inactivated microbial cells or cell components, with or without metabolites, that contribute to observed health benefits. The panel also discussed existing evidence of health-promoting effects of postbiotics, potential mechanisms of action, levels of evidence required to meet the stated definition, safety and implications for stakeholders. The panel determined that a definition of postbiotics is useful so that scientists, clinical triallists, industry, regulators and consumers have common ground for future activity in this area. A generally accepted definition will hopefully lead to regulatory clarity and promote innovation and the development of new postbiotic products.

[Evaluation of Safety Information of the Foods with Function Claims Based on Adverse Event Reports in Information System on Safety and Effectiveness for Health Foods Database]

Foods with Function Claims are allowed to label health claims based on scientific evidence evaluated by the manufacturers. To prevent health problems caused by inadequate use, the manufacturers should label proper safety information. To evaluate whether safety information is sufficiently provided, we conducted the adverse event review focused on popular functional ingredients using the database; Information system on safety and effectiveness for health food. The data suggested that causal factor of adverse events related to products containing soy isoflavone, ginkgo biloba extract and docosahexaenoic acid/eicosapentaenoic acid were overdose intake, concomitant use with certain medicines, and use by whom with an allergic predisposition. However, the safety information on the label was insufficient to prevent adverse events on each products' label. It is important not only to encourage food manufacturers to provide sufficient information based on safety review, but also to inform consumers about adverse events.

Quality of Systematic Reviews of the Foods with Function Claims in Japan: Comparative Before- and After-Evaluation of Verification Reports by the Consumer Affairs Agency

Background: In Japan, a new type of foods with health claims, called Foods with Function Claims (FFC), was introduced in April 2015 in order to make more products available that are clearly labeled with certain health functions. Regarding substantiating product effectiveness, scientific evidence for the proposed function claims must be explained by systematic reviews (SRs), but the quality of SRs was not clear. The objectives of this review were to assess the quality of SRs based on the FFC registered on the Consumer Affairs Agency (CAA) website in Japan, and to determine whether the CAA’s verification report in 2016 was associated with improvement in the quality of SRs. Methods: We evaluated the reporting quality of each SR by the AMSTAR checklist on methodological quality. We searched the database from 1 April to 31 October 2015 as the before-SR and from 1 July 2017 to 31 January 2018 as the after-SR. Results: Among the 104 SRs reviewed, 96 final products were included: 51 (53.1%) were supplements, 42 (43.8%) were processed foods without supplements, and 3 (3.1%) were fresh foods. Of the 104 SRs, 92 (88.5%) were qualitative reviews (i.e., without meta-analysis) and 12 (11.5%) performed a meta-analysis. The average quality score of before-SRs and after-SRs was 6.2 ± 1.8 and 5.0 ± 1.9, respectively, a statistically significant decrease (p < 0.001). Conclusion: Overall, the methodology and reporting quality of after-SRs based on the FFC were poorer than those of before-SRs. In particular, there were very poor descriptions and/or implementations of study selection and data extraction, search strategy, evaluation methods for risk of bias, assessment of publication bias, and formulating conclusions based on methodological rigor and scientific quality of the included studies.

The ascent of the blessed: regulatory issues on health effects and health claims for probiotics in Europe and the rest of the world

The outcome of the first series of health claim applications for probiotics in Europe as evaluated by the European Food Safety Authority (EFSA) has, up to 2013 almost completely yielded negative results. All recent applications also have been rejected, including the latest on prevention of mastitis in breastfeeding mothers. In other developed countries, such as Switzerland, Japan and Canada, the health effects of probiotics, for which scientific evidence has been provided, can be communicated to potential consumers. The number of clinical trials with probiotics over recent years shows a trend to level off or even decline. At the same time, clinical research into the role of (gut) microbiota in a wide variety of diseases and conditions is booming. Ultimately, this may offer new indications for gut microbiota management by probiotics, prebiotics or other food supplements.

Functional foods for augmenting nitric oxide activity and reducing the risk for salt-induced hypertension and cardiovascular disease in Japan

High salt intake is one of the major dietary determinants of hypertension and cardiovascular disease in Japan and throughout the world. Although dietary salt restriction may be of clinical benefit in salt-sensitive individuals, many individuals may not wish, or be able to, reduce their intake of salt. Thus, identification of functional foods that can help protect against mechanistic abnormalities mediating salt-induced hypertension is an issue of considerable medical and scientific interest. According to the "vasodysfunction" theory of salt-induced hypertension, the hemodynamic abnormality initiating salt-induced increases in blood pressure usually involves subnormal vasodilation and abnormally increased vascular resistance in response to increased salt intake. Because disturbances in nitric oxide activity can contribute to subnormal vasodilator responses to increased salt intake that often mediate blood pressure salt sensitivity, increased intake of functional foods that support nitric oxide activity may help to reduce the risk for salt-induced hypertension. Mounting evidence indicates that increased consumption of traditional Japanese vegetables and other vegetables with high nitrate content such as table beets and kale can promote the formation of nitric oxide through an endothelial independent pathway that involves reduction of dietary nitrate to nitrite and nitric oxide. In addition, recent studies in animal models have demonstrated that modest increases in nitrate intake can protect against the initiation of salt-induced hypertension. These observations are: (1) consistent with the view that increased intake of many traditional Japanese vegetables and other nitrate rich vegetables, and of functional foods derived from such vegetables, may help maintain healthy blood pressure despite a high salt diet; (2) support government recommendations to increase vegetable intake in the Japanese population.