The Web of Science Core Collection (WoSCC) is widely used for bibliometric analysis, which is the most authoritative citation-based database with powerful indexing functions (10, 11). Therefore, literature related to TRE was downloaded from the WoSCC. For TRE, there are two forms of expression including time restricted feeding and time restricted eating, so the search term was TS = “time restricted feeding” or “time restricted eating” or “time-restricted feeding” or “time-restricted eating.” The search results were confined by types of articles and reviews, publication data from inception to May 1, 2022, and language of English.

The relevant records with “Full Record and Cited References” were exported in the format of “Plain Text.” The resulting set of publications was analyzed bibliometrically. The top 10 high-yield authors, institutions, country/region and journals according to publications and the characteristics of the top 20 highest cited publications were summarized.

VOSviewer is a bibliometric tool which is developed for constructing and viewing bibliometric maps (12, 13). The distance and color represent these nodes are distributed in two-dimensional spaces (associations and the times). The larger its label and its circle when the more important an item. In our study, VOSviewer 1.6.16 software was used to perform co-authorship of a complete list of authors, organizations, countries, citations of journal and publications, and co-occurrence of all keywords. The minimum number set for the network was five.

A total of 414 publications (298 articles and 116 reviews) were included, which was shown in Figure 1. The Publications in this field of TRE showed an upward trend from 2016 sharply. The top subject categories in the analyzed publications were nutrition dietetics (161 publications) and endocrinology metabolism (64 publications), which was shown in Figure 2.

A total of 2016 authors contributed to this field. Among them, Satchidananda Panda was the most productive author from the United States with 26 publications and an H-index of 15, followed by Krista A Varady with 12 publications and an H-index of 8, Emily NC Manoogian with 11 publications and an H-index of 5, Kelsey Gabel with nine publications and an H-index of 5 and Grant M Tinsley with 8 publications and an H-index of 6. Satchidananda Panda, Krista A Varady and Emily N C Manoogian were the most frequently cited authors. The co-authorship map of the authors was shown in the Figure 3A.

All publications were distributed from about 624 organizations from 49 Countries/Regions. The leading institutions were the Salk Institute for Biological Studies (24 publications with 4,003 citations), University of California San Diego (16 Publications with 2,644 citations), the University of Alabama at Birmingham (13 publications with 1,088 citations), University of Illinois (13 publications with 617 citations) and Texas Tech University (10 publications with 609 citations). The network visualization map of institutions was shown in Figure 3B. For Country/Region, the United States had the most publications with 184 documents, followed by the People’s Republic of China (33 documents), Japan (32 documents), Australia (24 documents) and Italy (21 documents). The network visualization map of the Country/Region was shown in Figure 3C. The top 10 high-yield authors, institutions and country/regions according to publications were summarized in Table 1.

All publications were from 182 journals. Among them, Nutrients was the most productive journal with 65 documents and 972 citations, which was followed by Frontiers in Nutrition with 13 documents and 101 citations, and Cell Metabolism with 10 documents and 3,224 citations. The most frequently cited journal was Cell Metabolism. The network visualization map of all journals was shown in Figure 4A. The top 10 high-yield according to publications were summarized in Table 2.

The characteristics of the top 20 highest cited publications were summarized in Table 3 (6, 14–32). The top three high cited articles were as follows: the first article with 991 citations was published in Cell Metabolism and authored by Hatori et al. (16). In this article, they found that mice with TRF were protected against hyperinsulinemia, inflammation, hepatic steatosis and obesity. The TRF regimen could improve oscillations of the circadian clock and target genes’ expression and mTOR, CREB, and AMPK pathway function. They demonstrated that the TRF regimen was a non-pharmacological approach against obesity and associated diseases in mice. The second article with 442 citations was published in Cell Metabolism and authored by Chaix et al. (14). In this article, they tested TRF in mice under diverse nutritional challenges and found that TRE could attenuate metabolic diseases from different obesogenic diets, and the protective effects existed even if the TRF was temporarily interrupted. TRF could stabilize and reverse the progression of metabolic diseases in mice with preexisting type II diabetes and obesity. They established clinically relevant parameters of TRF and believed that TRE could prevent and treat obesity and metabolic disorders including hepatic steatosis, hypercholesterolemia and type II diabetes. The third article with 417 citations was published in Cell Metabolism and authored by Sutton et al. (27), and it is the first trial of early TRE. In this study, they could improve appetite, oxidative stress, cell responsiveness, blood pressure, and insulin sensitivity in men with prediabetes. They showed that early TRF (eTRF) improves some aspects of cardiometabolic health in humans for the first time and these effects were not solely due to weight loss. The network visualization map of cited documents was shown in Figure 4B.

The network visualization map of keywords was shown in Figure 5, and the clusters of red, green, yellow and blue, including four indicating research directions. The keywords of the green cluster were time-restricted feeding, metabolism, circadian clock, and circadian rhythm. The keywords of the blue cluster were obesity, health, diet, and food intake. The keywords of the red cluster were intermittent fasting, weight loss, caloric restriction, and time-restricted eating. The keywords of the yellow cluster were insulin resistance, metabolic disease, cardiovascular disease, and caloric intake.

To our best knowledge, this is the first study of bibliometric and visual analysis for TRE. In our study, a total of 414 publications with 298 articles and 116 reviews were included. The publications in this field showed an upward trend from 2016. A total of 2016 authors contributed to this field.

The most productive authors were Satchidananda Panda, Krista A Varady, and Emily NC Manoogian. All publications were distributed from about 624 organizations from 49 Countries/Regions. The leading institutions were the Salk Institute for Biological Studies, the University of California San Diego and the University of Alabama at Birmingham, and the most productive countries were the United States, the People’s Republic of China and Japan. All publications were from 182 journals, and the most productive journals were Nutrients, Frontiers in Nutrition and Cell Metabolism. The first highest cited reference with 991 citations was published in Cell Metabolism, and authored by Satchidananda Panda et al. There were four indicating research directions, and the keywords of the green cluster were time-restricted feeding, metabolism, circadian clock, and circadian rhythm. The keywords of the blue cluster were obesity, health, diet, and food intake. The keywords of the red cluster were intermittent fasting, weight loss, caloric restriction, and time-restricted eating. The keywords of the yellow cluster were insulin resistance, metabolic disease, cardiovascular disease, and caloric intake.

In this bibliometric analysis, most of the articles were published from the United States, the People’s Republic of China and Japan, and the percentage of articles from the United States was 44%(184/414). Of the top 10 institutions, seven were from the United States. Of the top 10 productive author, six were from the United States. In the field of TRE, the prominent contribution was from the United States. It indicates that the studies from other countries need to be enhanced.

Through the combination of highest cited references and analysis of all keywords co-occurrence clusters, the research hotspots and frontiers were as follows: (1) TRE and circadian rhythm. In the top 20 highest cited references, five explored the TRE and the circadian rhythm, and the keywords of circadian clock and circadian were in the green cluster (6, 17, 19, 21, 25). The rhythm internal circadian rhythms play an important role in physiology and overall health (21). Disrupted circadian rhythms would compromise health and increase the risk of disease. Erratic lifestyle including jet-lag, shift work and aberrant sleep and eating patterns contribute to circadian rhythm disruption, which compromises multiple levels of physiology for inflammation and metabolism, and increases the risk for cardiovascular disease, obesity and metabolic disease. Researches in rodents have demonstrated that TRE could restore robust circadian rhythms and improve health, and decrease the risk of disease to extend healthspan. (2) TRE and obesity. In the top 20 highest cited references, four explored the TRE and obesity, and the keyword of obesity was in the blue cluster (6, 14, 20, 29). Cienfuegos et al. (33) showed that 6 and 4-h TRF could induce mild reductions in body weight and may be promising interventions for weight loss. Lowe et al. (20) demonstrated there was a significant weight loss in the TRE group but not in e consistent meal timing (CMT) group. A systematic review and meta-analysis showed that the TRF regimen had a significant weight loss compared with the unrestricted time regimen, which was mainly attributed to the loss of lean mass, not fat mass (20, 33–39). Recently, Liu et al. (40) showed that, compared with calorie restriction (CR), TRE was not more beneficial in the reduction of body weight and body fat. Thomas et al. (41) demonstrated that early TRE plus daily CR (E-TRE + DCR) resulted in similar levels of weight loss compared with DCR alone, and may be an acceptable dietary strategy. A recent study (42) has demonstrated that 30%-CR could extend lifespan by 10% while TRE and CR act together extended lifespan by 35% in male C57BL/6J mice, and this effect was independent of body weight. Although a regimen of TRE was not more beneficial for the reduction in body weight compared with CR, the effect of TRE on other factors such as longevity should be explored in further studies. (3) TRE and metabolic disease. In the top 20 highest cited references, six explored TRE and metabolic disease, and the keywords of metabolic disease and insulin resistance were in the yellow cluster (6, 16, 24, 27, 30, 43). Wilkinson et al. (30) demonstrated that TRE could improve the cardiometabolic health of patients with metabolic syndrome and could be added to standard medical practice. Sutton et al. (27) did the first study to prove that eTRF could improve some aspects of cardiometabolic health which were not solely due to weight loss. In their study, they found that eTRF could improve appetite, oxidative stress, cell responsiveness, blood pressure, and insulin sensitivity in men with prediabetes. (4) TRE and cardiovascular disease. In the top 20 highest cited references, three explored TRE and cardiovascular disease, and the keyword of cardiovascular disease was in the yellow cluster (15, 24, 27). Several trails (24, 27, 43–45) have evaluated the effect of TRE on parameters of cardiovascular health including plasma lipid concentrations and blood pressure. Wilkinson et al reported that TRF led to 12% reductions for LDL cholesterol levels in subjects with metabolic syndrome. Two studies reported minor decreases in triglyceride levels. Some studies reported decreases in diastolic (7–9%) and systolic (4–9%) blood pressure.

This was the first study to conduct a bibliometric analysis of TRE. In our study, we displayed the research status and draw visual maps, and explored trends and hotspots in this field to provide the reference for future studies. There were several limitations in our study. First, all data were extracted from the WoSCC, and other databases such as Medline and Embase were not used. Second, only studies published in English were included. Finally, bias may still exist despite our normalization procedures. Further studies will provide new insight into this field.