Background
Obesity is associated with increased mortality as a significant risk factor for chronic diseases, including cardiovascular diseases and cancer. Several people believe that weight gain is harmful, and weight loss helps maintain health. However, some studies have shown that weight loss, particularly among older adults, is more likely to increase the risk of mortality than weight gain.
Methods
We used data for the cohort of the Korean Longitudinal Study of Aging, which is a nationwide stratified multi-stage sample of adults aged 45 years. The all-cause mortality risk was assessed using the survival status and the number of months of survival calculated from 2006 (baseline year) to 2016. Cox proportional hazard regression were used to study the causal link between weight change and all-cause mortality risk.
Results
The results showed interactive associations between weight loss and mortality among middle-aged and older adults. The hazard ratio was 1.62 (95% confidence interval [CI], 1.10–2.40) for the participants aged 45–65 years with weight losses greater than 5 kg and 1.56 (95% CI, 1.29–1.89) for those older than 65 years with weight losses greater than 5 kg. The results for the group with weight gain above 5 kg were not significant. Middle-aged and older men showed an increase in all-cause mortality associated with weight loss of more than 5 kg, but only the older women showed significant results.
Conclusion
This large-scale cohort study in Korea showed a relationship between weight loss and all-cause mortality in middle-aged and older individuals.

Citations

• Body mass index trajectories and all-cause mortality in older Chinese adults: Hong Kong’s Elderly Health Service Cohort
  Man Ki Kwok, Siu Yin Lee, Gabriel M Leung, C Mary Schooling
  Journal of Epidemiology and Community Health.2025; 79(9): 698.     CrossRef
• Associations of obesity indices change with cardiovascular outcomes: a dose-response meta-analysis
  Lyu Wang, Hanyue Ding, Yunyang Deng, Junjie Huang, Xiangqian Lao, Martin C. S. Wong
  International Journal of Obesity.2024; 48(5): 635.     CrossRef
• Social isolation and depression as risk factors for weight loss of 5kg or more among older Korean adults
  Youngjoon Bae, Mark C. Pachucki, Ellen L. Idler
  PLOS ONE.2024; 19(3): e0299096.     CrossRef
• Associations of short‐term changes in obesity indices with all‐cause mortality and cardiovascular disease
  Lyu Wang, Yun‐Yang Deng, Tsung Yu, Xiang‐Qian Lao, Martin C. S. Wong
  Obesity.2024; 32(8): 1568.     CrossRef
• In-hospital outcomes of older patients with gastric cancer and their risk factors: large comprehensive institution-based study
  Lei Huang, Yunmei Liu, Lei Wang, Lan Rong, Weiguo Hu
  European Geriatric Medicine.2024; 15(6): 1909.     CrossRef
• Weight loss rather than weight gain has a detrimental effect on successful aging in older adults: A 4-year longitudinal study in China
  Nan Liu, Tao Liu, Yihan Pan, Jin Wang, Xiaoguang Zhao
  Geriatric Nursing.2024; 60: 297.     CrossRef
• Association of weight change with all-cause and cause-specific mortality: an age-stratified analysis
  Qing-Mei Huang, Dong Shen, Jian Gao, Huan Chen, Jia-Hao Xie, Hao-Yu Yan, Bin Wu, Zhi-Hao Li, Gang Liu, Chen Mao
  BMC Medicine.2024;[Epub]     CrossRef
• Associations of Change in Body Size With All-Cause and Cause-Specific Mortality Among Healthy Older Adults
  Sultana Monira Hussain, Anne B. Newman, Lawrence J. Beilin, Andrew M. Tonkin, Robyn L. Woods, Johannes T. Neumann, Mark Nelson, Prudence R. Carr, Christopher M. Reid, Alice Owen, Jocasta Ball, Flavia M. Cicuttini, Cammie Tran, Yuanyuan Wang, Michael E. Er
  JAMA Network Open.2023; 6(4): e237482.     CrossRef
• Association between Weight Loss and Hand-Grip Strength with Cause-Specific Mortality in Middle-Aged and Older Adults
  Inhwan Lee
  Exercise Science.2023; 32(3): 339.     CrossRef
• Weight Change and Risk of Atherosclerosis Measured by Carotid Intima–Media Thickness (cIMT) from a Prospective Cohort—Analysis of the First-Wave Follow-Up Data of the Canadian Longitudinal Study on Aging (CLSA)
  Jian Liu, Newman Sze, Miya Narushima, Deborah O’Leary
  Journal of Cardiovascular Development and Disease.2023; 10(10): 435.     CrossRef
• Weight maintenance and gain were significantly associated with lower risk of all-cause and cancer-related mortality in Korean adults who were newly diagnosed with cancer based on the Korean NHIS-HEALS cohort
  Yong-June Kim, Seung Park, Won Tae Kim, Yoon-Jong Bae, Yonghwan Kim, Hee-Taik Kang
  Medicine.2023; 102(47): e36184.     CrossRef
• Obesity in Caucasian Seniors on the Rise: Is It Truly Harmful? Results of the PolSenior2 Study
  Monika Puzianowska-Kuznicka, Alina Kurylowicz, Lukasz Wierucki, Aleksander Jerzy Owczarek, Kacper Jagiello, Malgorzata Mossakowska, Tomasz Zdrojewski, Jerzy Chudek
  Nutrients.2022; 14(21): 4621.     CrossRef