Yo‑yo dieting study surprise
A 10‑year study from Ben‑Gurion University (Prof. Iris Shai) reports that cycles of weight loss and regain still produced lasting metabolic benefits—reducing visceral fat and creating a ‘cardiometabolic memory’ despite weight regain. It’s a counterintuitive result that could reframe how we think about intermittent weight‑loss strategies. (x.com)
The peer‑reviewed report, titled “How effective is rejoining a long‑term weight loss program? The 5‑ and 10‑year MRI‑assessed Follow Interventions Trial (FIT) project,” was published in BMC Medicine on January 30, 2026 and is based on follow‑ups conducted in 2022–2024. (link.springer.com) Researchers pooled two randomized 18‑month dietary trials—CENTRAL (2012–2014) and DIRECT‑PLUS (2017–2018)—and the analysis included 572 trial observations contributed by 480 unique participants, of whom 92 participated in both trials. (link.springer.com) Abdominal‑fat compartments were measured by MRI using a Philips Ingenia 3.0‑Tesla scanner and MATLAB‑based semiautomated software to quantify visceral adipose tissue (VAT), deep and superficial subcutaneous adipose tissue (SAT). (link.springer.com) At the start of their second enrollment, the 92 rejoiners showed lower VAT area (135.5 cm^2) than at their initial baseline (160.0 cm^2), and improved metabolic markers including HOMA‑IR (3.8 vs 4.5) and HDL‑C/Triglycerides ratio (3.6 vs 4.2). (link.springer.com) The magnitude of change differed by intervention: rejoiners’ VAT fell −33.3% during their first intervention versus −7.2% during the second, deep‑SAT fell −31.9% then −4.0%, and overall weight change per intervention declined from −3.5% to −1.5%. (link.springer.com) Five years after the second trial, rejoiners experienced markedly less weight regain (+0.2% vs +2.9%) and smaller regains in deep‑SAT (+2.4% vs +13.3%) and superficial‑SAT (+12.8% vs +24.3%); overall follow‑up rates were 384 of 480 participants (80%) with 76 of 92 rejoiners (83%) re‑evaluated. (link.springer.com) The multi‑institution author list includes Iris Shai alongside collaborators from Harvard T.H. Chan School of Public Health, Leipzig University and other centers, and Ben‑Gurion University issued a press summary highlighting the study’s long‑term MRI data. (link.springer.com)
