A group of researchers at the University Hospital of Bordeaux in France has found that weight cycling, commonly called the Yo-Yo Diet, raises the risk of kidney disease in people with type 1 diabetes. The study was published in the Journal of Clinical Endocrinology and Metabolism, a leading journal for endocrinology and metabolism research. The team notes that fluctuations in body weight over time can correlate with changes in kidney function and may influence how clinicians monitor and protect renal health in type 1 diabetes patients.
The Yo-Yo Diet is defined by repeated cycles of losing weight and regaining it. It is reported to occur in a sizable portion of adults, with roughly 35 percent of men and 55 percent of women experiencing weight cycling in various populations. The term mirrors the motion of a yo-yo toy, which rises and falls along a string, symbolizing the up and down pattern of weight during dieting and relapse.
Previously, weight cycling has been linked to a higher risk of cardiovascular disease in the general population and in people with type 2 diabetes. The new findings extend this pattern to kidney health, suggesting that repeated weight changes may have broader consequences for chronic disease management beyond heart health alone.
In this analysis, researchers used data from 1,432 participants who were part of the DCCT and later followed through the EDIC observational study. For each participant, six years of body-weight data were examined using the variability independent of the mean index, a measure that captures weight fluctuations beyond what would be expected from a person’s average weight. This approach helps distinguish true weight variability from shifts that simply reflect different overall body sizes, providing a clearer link between weight cycling and kidney outcomes.
The results showed that participants with greater weight fluctuations experienced a meaningful decline in kidney function over time, as indicated by a reduction in estimated glomerular filtration rate and a higher occurrence of albumin in the urine. Albuminuria serves as an early marker of kidney disease, signaling that the kidneys are leaking protein into the urine. These associations were more evident among individuals who exhibited the largest weight cycling patterns, underscoring a potential dose–response relationship between weight variability and renal risk.
Although the precise mechanisms behind how weight fluctuations may damage the kidneys are not fully clarified, several hypotheses are discussed. One possibility involves the interplay between insulin therapy used to manage type 1 diabetes and weight changes that occur with dieting. Another consideration is that frequent weight cycling imposes intermittent metabolic and cardiovascular stress, which could add strain to kidney function and accelerate injury over time.
Earlier investigations have suggested that obesity, in itself, does not automatically shorten life expectancy in every context. The current findings stress that weight stability might play a critical role in preserving kidney health for people living with type 1 diabetes and may inform more nuanced weight-management strategies in this population.