Medical Bulletin 28/February/2026

Here are the top medical news for today:Moderate Exercise Linked to Lower Risk of Sarcopenic Obesity in Seniors: StudyOlder adults who remain physically active have a significantly lower risk of developing sarcopenic obesity-a serious condition characterized by excess body fat combined with reduced muscle strength.
According to new research from Örebro University, even activity levels below current exercise recommendations can offer meaningful protection. The findings were published in the Journal of Cachexia, Sarcopenia and Muscle.
Sarcopenic obesity is particularly concerning in people over 65 because it increases the likelihood of chronic diseases, frailty, mobility limitations, and loss of independence.
The study included more than 860 men and women aged 65–79 from four European countries. Unlike many previous studies that relied on self-reported activity, this research used motion sensors to objectively measure physical activity levels, providing more reliable data.
The results showed a strong association between physical activity and lower risk of sarcopenic obesity. Older adults who engaged in moderate exercise—such as brisk walking for approximately 75 minutes per week—had up to a 50% lower risk compared with those who were completely inactive. Participants with the highest activity levels demonstrated up to an 80% reduction in risk.
Importantly, the protective effects were not limited to structured workouts. Even low-intensity activities, including standing, slow walking, and general movement throughout the day, were associated with health benefits, particularly for individuals unable to perform vigorous exercise.
The findings remained significant after adjusting for factors such as diet, inflammation levels, and muscle-weakening diseases.
The study underscores that reducing sedentary time and incorporating regular movement into daily routines can play a crucial role in preserving muscle strength and metabolic health in older age.
REFERENCE: Nilsson, A., et al. (2025). Accelerometer‐Determined Physical Activity and Sarcopenic Obesity Risk in Older European Men and Women. Journal of Cachexia, Sarcopenia and Muscle. DOI: 10.1002/jcsm.70149. https://onlinelibrary.wiley.com/doi/full/10.1002/jcsm.70149Research Links Widely Used Brain Supplement to Lower Male LongevityHigher blood levels of the amino acid tyrosine may be linked to shorter lifespans in men, according to a new study published in Aging-US.
The research was conducted by scientists from the University of Hong Kong and the University of Georgia. The team investigated whether circulating levels of phenylalanine and tyrosine are associated with overall mortality and life expectancy.
Phenylalanine and tyrosine are essential components of protein metabolism and are naturally present in foods such as meat, dairy, nuts, and legumes. Tyrosine is particularly important because it serves as a precursor for neurotransmitters like dopamine, norepinephrine, and epinephrine, which regulate mood, stress response, and cognitive function.
Although these amino acids are widely consumed and even marketed as supplements, their long-term effects on aging are not fully understood.
The researchers analyzed health and genetic data from more than 270,000 participants in the UK Biobank. Using both observational methods and Mendelian randomization—a genetic approach that helps clarify cause-and-effect relationships—they assessed whether higher amino acid levels were linked to shorter lifespans.
While initial analyses suggested both phenylalanine and tyrosine were associated with increased mortality risk, more rigorous modeling showed that only tyrosine had a consistent and potentially causal link, specifically in men.
The findings indicated that men with genetically higher tyrosine levels could live nearly one year less on average. No meaningful association was found in women. Researchers noted that men generally have higher tyrosine concentrations, which may partly contribute to sex-based differences in longevity.
Although the study did not directly evaluate tyrosine supplements, the results raise important questions about long-term intake and metabolic health. Further research is needed to understand the biological mechanisms involved and whether dietary adjustments could help support healthier aging.
REFERENCE: Jie V. Zhao, Yitang Sun, Junmeng Zhang, Kaixiong Ye. The role of phenylalanine and tyrosine in longevity: a cohort and Mendelian randomization study. Aging, 2025; 17 (10): 2500 DOI: 10.18632/aging.206326Older Vegetarians Show Reduced Chances of Living to 100, Research SuggestsOlder adults who avoid meat may be somewhat less likely to reach age 100-but only under specific circumstances-according to findings from the Chinese Longitudinal Healthy Longevity Survey. This large, nationally representative project followed more than 5,000 Chinese adults aged 80 and older from 1998 to 2018 to identify factors associated with exceptional longevity.
Researchers observed that participants who did not consume meat were less likely to become centenarians compared with those who did. However, this association was present only among individuals who were underweight.
The findings should not be interpreted as evidence that plant-based diets are harmful. Extensive research in younger and middle-aged populations has consistently linked vegetarian and plant-forward eating patterns to lower risks of cardiovascular disease, stroke, type 2 diabetes, and obesity. These benefits are typically attributed to higher fiber intake, lower saturated fat consumption, and improved metabolic health. However, nutritional priorities change significantly in advanced age.
After 80, the body undergoes physiological shifts, including reduced appetite, lower energy expenditure, declining muscle mass, and bone density loss. These changes increase the risk of frailty, falls, fractures, and malnutrition. In this stage of life, maintaining adequate body weight and preserving muscle strength often become more important than long-term chronic disease prevention.
Importantly, the study found no reduced likelihood of reaching 100 among older adults of healthy weight who avoided meat. Additionally, individuals who consumed fish, eggs, or dairy products did not show a lower probability of exceptional longevity. These animal-source foods provide high-quality protein and key nutrients such as vitamin B12, calcium, vitamin D, and essential amino acids that support muscle and bone health.
Because the study was observational, it cannot establish cause and effect. Still, it highlights that dietary needs evolve with age. In very old, underweight adults, ensuring sufficient protein and nutrient intake may play a critical role in supporting healthy longevity.
REFERENCE: Yaqi Li, Kaiyue Wang, Yuebin Lv, Guliyeerke Jigeer, Yilun Huang, Xiuhua Shen, Xiaoming Shi, Xiang Gao. Vegetarian diet and likelihood of becoming centenarians in Chinese adults aged 80 y or older: a nested case-control study. The American Journal of Clinical Nutrition, 2026; 123 (2): 101136 DOI: 10.1016/j.ajcnut.2025.101136