{"doi":"10.2196/15835","title":"Intervention Enhancement Strategies Among Adults With Type 2 Diabetes in a Very Low–Carbohydrate Web-Based Program: Evaluating the Impact With a Randomized Trial","abstract":"Background Adults with type 2 diabetes may experience health benefits, including glycemic control and weight loss, from following a very low–carbohydrate, ketogenic (VLC) diet. However, it is unclear which ancillary strategies may enhance these effects. Objective This pilot study aims to estimate the effect sizes of 3 intervention enhancement strategies (text messages, gifts, and breath vs urine ketone self-monitoring) that may improve outcomes of a 12-month web-based ad libitum VLC diet and lifestyle intervention for adults with type 2 diabetes. The primary intervention also included other components to improve adherence and well-being, including positive affect and mindfulness as well as coaching. Methods Overweight or obese adults (n=44; BMI 25-45 kg/m2) with type 2 diabetes (glycated hemoglobin [HbA1c] ≥6.5%), who had been prescribed either no glucose-lowering medications or metformin alone, participated in a 12-month web-based intervention. Using a 2×2×2 randomized factorial design, we compared 3 enhancement strategies: (1) near-daily text messages about the intervention’s recommended behaviors (texts n=22 vs no texts n=22), (2) mailed gifts of diet-relevant foods and cookbooks (6 rounds of mailed gifts n=21 vs no gifts n=23), and (3) urine- or breath-based ketone self-monitoring (urine n=21 vs breath n=23). We assessed HbA1c and weight at baseline and at 4, 8, and 12 months. We evaluated whether each strategy exerted a differential impact on HbA1c and weight at 12 months against an a priori threshold of Cohen d of 0.5 or greater. Results We retained 73% (32/44) of the participants at 12 months. The intervention, across all conditions, led to improvements in glucose control and reductions in body weight at the 12-month follow-up. In intent-to-treat (ITT) analyses, the mean HbA1c reduction was 1.0% (SD 1.6) and the mean weight reduction was 5.3% (SD 6.0), whereas among study completers, these reductions were 1.2% (SD 1.7) and 6.3% (SD 6.4), respectively, all with a P value of less than .001. In ITT analyses, no enhancement strategy met the effect size threshold. Considering only study completers, 2 strategies showed a differential effect size of at least a d value of 0.5 or greater Conclusions Text messages, gifts of food and cookbooks, and urine-based ketone self-monitoring may potentially enhance the glycemic or weight loss benefits of a web-based VLC diet and lifestyle intervention for individuals with type 2 diabetes. Future research could investigate other enhancement strategies to help create even more effective solutions for the treatment of type 2 diabetes. Trial Registration ClinicalTrials.gov NCT02676648; http://clinicaltrials.gov/ct2/show/NCT02676648","journal":"JMIR Diabetes","year":2020,"id":79693,"datarank":0.7149328904914722,"base_score":2.833213344056216,"endowment":2.833213344056216,"self_citation_contribution":0.42498200160843247,"citation_network_contribution":0.28995088888303977,"self_endowment_contribution":0.42498200160843247,"citer_contribution":0.28995088888303977,"corpus_percentile":null,"corpus_rank":null,"citation_count":16,"citer_count":9,"citers_with_citation_signal":7,"citers_with_endowment":7,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9575,"is_data_producer":true,"deposit_databanks":{"ClinicalTrials.gov":["NCT02676648"]},"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2020-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":413812,"name":"Judith T. Moskowitz","orcid":"0000-0002-1399-3318","position":1,"is_corresponding":false},{"id":413813,"name":"Ashley E. Mason","orcid":"0000-0002-8744-0185","position":2,"is_corresponding":false},{"id":413814,"name":"Jennifer Daubenmier","orcid":"0000-0001-5678-4068","position":3,"is_corresponding":false},{"id":413815,"name":"Bradley Liestenfeltz","orcid":"0000-0001-9203-5881","position":4,"is_corresponding":false},{"id":413816,"name":"Amanda L. Missel","orcid":"0000-0002-9879-0519","position":5,"is_corresponding":false},{"id":413817,"name":"Hovig Bayandorian","orcid":"0000-0003-4596-0323","position":6,"is_corresponding":false},{"id":413818,"name":"James E. Aikens","orcid":"0000-0002-3795-9018","position":7,"is_corresponding":false},{"id":29199,"name":"Sarah Kim","orcid":"0000-0002-3599-5509","position":8,"is_corresponding":false},{"id":286358,"name":"Frederick Hecht","orcid":"0000-0002-5782-1171","position":9,"is_corresponding":false},{"id":413811,"name":"Laura R. Saslow","orcid":"0000-0003-3991-3205","position":0,"is_corresponding":true}],"reference_count":38,"raw_metadata":null,"created_at":"2026-07-18T21:50:57.971597Z","pmid":"32902391","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}