Medical Bulletin 24/October/2025 - Video

Here are the top medical news for the day:

Can Taking 4,000 Steps Just Once a Week Lower Risk of Death and Heart Disease?

Published in The British Journal of Sports Medicine, a new study by Mass General Brigham researchers reveals that even minimal step activity, just one or two days per week can significantly reduce mortality and cardiovascular risk in older women.

For years, the daily step goal of 10,000 has been touted as a benchmark for good health. But new research suggests that far fewer steps, taken even sporadically, can still provide meaningful health benefits. In a large study involving 13,574 older women, scientists from Mass General Brigham found that taking just 4,000 steps on one or two days per week was linked to a 26% lower risk of death and a 27% reduced risk of cardiovascular disease over ten years.

The study was conducted as part of a federally funded project involving participants from the Women’s Health Study at Brigham and Women’s Hospital (BWH).

These women, with an average age of 71.8 and no prior history of cardiovascular disease or cancer, wore accelerometers for seven days between 2011 and 2015 to record their step counts. Their health outcomes were then tracked over the following decade.

Participants were categorized based on how many days per week they achieved step counts at or above 4,000, 5,000, 6,000, or 7,000 steps. The most significant benefit was seen in women who achieved 4,000 steps one or two days weekly. Notably, those who reached that step count on three or more days had an even greater reduction in mortality up to 40%. However, as step counts increased, the benefits to cardiovascular health began to level off.

Interestingly, the study found that it was the total number of steps taken that mattered most—not how consistently they were spread across the week. This suggests that there isn’t a ‘better’ way to get steps.

Senior author I-Min Lee, MBBS, ScD, emphasized the study’s public health value: “Because of today’s low step counts, it’s increasingly important to determine the minimum amount of physical activity required to improve health outcomes, so that we can offer realistic and feasible goals for the public.”

Reference: Hamaya R et al. “Association between frequency of meeting daily step thresholds and all-cause mortality and cardiovascular disease in older women” British Journal of Sports Medicine DOI: 10.1136/bjsports-2025-110311

Cochrane Review Supports Immediate Skin-to-Skin Contact as Evidence-Based Standard for Neonatal Care

Immediate skin-to-skin contact between mothers and newborns should now be considered the global standard of care, according to a newly updated review published in the Cochrane Database of Systematic Reviews. The analysis, which draws on data from 69 trials involving over 7,000 mother-infant pairs, found compelling evidence that placing babies on their mother’s bare chest within the first hour of birth significantly improves breastfeeding rates, body temperature regulation, blood sugar levels, and other vital health outcomes.

The updated review adds 26 new studies to the 2016 version, which already influenced 20 international health guidelines, including recommendations from the World Health Organization (WHO).

Researchers analyzed trials conducted mostly in high- and middle-income countries, where babies who received immediate skin-to-skin contact were 20% more likely to be exclusively breastfed at one month compared to those who were separated from their mothers after birth—75% versus 55%.

Exclusive breastfeeding has well-documented benefits for infant development, maternal health, and healthcare systems.

Given the overwhelming benefits, the review states that conducting new randomized trials that deny skin-to-skin contact to a control group is no longer ethical. “Withholding skin-to-skin contact would now be considered unethical, as there is enough evidence to show that the practice improves newborn health and survival,” said Karin Cadwell, senior author and Executive Director of Healthy Children Project’s Center for Breastfeeding.

The authors now urge future research to focus on improving implementation, especially in low-income settings where the practice could save lives, particularly among low birth weight infants.

Reference: Moore ER, Brimdyr K, Blair A, Jonas W, Lilliesköld S, Svensson K, Ahmed AH, Bastarache LR, Crenshaw JT, Giugliani ER J, Grady JE, Zakarija-Grkovic I, Haider R, Hill RR, Kagawa MN, Mbalinda SN, Stevens J, Takahashi Y, Cadwell K. Immediate or early skin‐to‐skin contact for mothers and their healthy newborn infants. Cochrane Database of Systematic Reviews 2025, Issue 10. Art. No.: CD003519. DOI: 10.1002/14651858.CD003519.pub5. Accessed 22 October 2025.

Soft drink consumption may trigger depression by disturbing gut bacteria balance: Study

Researchers have found a compelling link between soft drink consumption and major depressive disorder (MDD), especially in women. This study, published in JAMA Psychiatry, analyzed data from the Marburg-Münster Affective Cohort Study (MACS), involving 932 adults aged 18-65, including 405 diagnosed with MDD and 527 healthy controls.

Soft drinks, popular especially among children and teens, are loaded with simple sugars like glucose and fructose, spiking blood sugar levels. Excess sugar that the intestine can’t absorb fuels the growth of harmful gut bacteria, which cause inflammation and weaken the gut’s protective barrier. This triggers systemic and brain inflammation linked to anxiety and learning issues. Meanwhile, diets promoting anti-inflammatory short-chain fatty acids (SCFAs) from beneficial bacteria support gut health and reduce inflammation, counteracting these negative effects of sugary drinks.

The researchers used multivariable regression and analysis of variance (ANOVA) to explore associations between soft drink intake and depression diagnosis and symptom severity. They also conducted mediation analyses to examine if specific gut bacteria—Eggerthella and Hungatella—were involved. Soft drink consumption was self-reported, and gut microbiome diversity was assessed from stool samples.

Findings revealed that each additional soft drink increased the odds of depression by 8%. Notably, women who consumed more soft drinks had nearly 16% higher odds of depression and greater symptom severity, while no such association was seen in men. Depressed individuals showed higher body mass indexes (BMI), but adjusting for BMI and antidepressant use did not alter the findings. Women with depression also exhibited altered gut microbiomes, with elevated levels of Eggerthella, a bacterium linked to inflammation and mood regulation. Mediation analysis indicated that this bacterium partly explained the relationship between soft drink intake and depression.

The authors caution that, as an observational study, causality cannot be confirmed, and bi-directional effects may exist, with depressed women possibly consuming more soft drinks. Nevertheless, the data emphasize the urgent need for public health strategies to reduce soft drink consumption, especially among women, to potentially mitigate depression risk and improve gut health.

Reference: Thanarajah, S. E., Ribeiro, A. H., Lee, J., et al. (2025). Soft Drink Consumption and Depression Mediated by Gut Microbiome Alterations. JAMA Psychiatry. doi: doi: 10.1001/jamapsychiatry.2025.2579. https://jamanetwork.com/journals/jamapsychiatry/fullarticle/2839019