Medical Bulletin 11/ April/ 2025 - Video

A new study suggests that eating only during the daytime could help people avoid the health risks associated with shift work. Results are published in Nature Communications.

For the study, researchers enlisted 20 healthy young participants to a two-week in-patient study at the Brigham and Women’s Center for Clinical Investigation. They had no access to windows, watches, or electronics that would clue their body clocks into the time. The effect of circadian misalignment could be determined by comparing how their body functions changed from before to after simulated night work.

Study participants followed a “constant routine protocol,” a controlled laboratory setup that can tease apart the effects of circadian rhythms from those of the environment and behaviors. During this protocol, participants stayed awake for 32 hours in a dimly lit environment, maintaining constant body posture and eating identical snacks every hour. After that, they participated in simulated night work and were assigned to either eating during the nighttime or only during the daytime. Finally, participants followed another constant routine protocol to test the aftereffects of the simulated night work. Importantly, both groups had an identical schedule of naps, and, thus, any differences between the groups were not due to differences in sleep schedule.

The investigators examined the aftereffects of the food timing on participants’ cardiovascular risk factors and how these changed after the simulated night work. Researchers measured various cardiovascular risk factors, including autonomic nervous system markers, plasminogen activator inhibitor-1, and blood pressure.

Remarkably, these cardiovascular risk factors increased after simulated night work compared to the baseline in the participants who were scheduled to eat during the day and night.

“Our study controlled for every factor that you could imagine that could affect the results, so we can say that it’s the food timing effect that is driving these changes in the cardiovascular risk factors,” said Sarah Chellappa, MD, MPH, PhD, an associate professor at the University of Southampton, and lead author for the paper.

Reference: Chellappa, S.L., Gao, L., Qian, J. et al. Daytime eating during simulated night work mitigates changes in cardiovascular risk factors: secondary analyses of a randomized controlled trial. Nat Commun 16, 3186 (2025). https://doi.org/10.1038/s41467-025-57846-y

Relaxation techniques may help lower high blood pressure—at least in the short term—but the longer term effects are unclear, finds a pooled data analysis of the existing research published in the open access journal BMJ Medicine.

The researchers scoured research databases for studies, published in English up to February 2024 that looked at the potential impact of relaxation techniques on high blood pressure (140/90 mm Hg and above) and elevated blood pressure (120/80 mm Hg and above).

They included 182 studies, 166 of which looked at high blood pressure, and 16 of which looked at elevated blood pressure (pre-hypertension).

Where possible, the researchers deployed network meta analysis, a statistical technique used to simultaneously compare the effects of several different ‘treatments’.

The pooled results of 54 studies showed that most relaxation techniques seemed to lower both systolic and diastolic blood pressure for people with high blood pressure after 3 or fewer months. The most commonly included interventions were breath control (13 studies), yoga/tai chi (11), biofeedback (8), progressive muscle relaxation (7), and music (7).

Compared with no intervention, breath control achieved a reduction of 6.65 mm Hg in systolic blood pressure (the first and higher number in a blood pressure reading), meditation a drop of 7.71 mm Hg, meditative movement, such as tai chi and yoga, a drop of 9.58 mm Hg, and mindfulness a drop of 9.90 mm Hg.

Music was also associated with a fall of 6.61 mm Hg, progressive muscle relaxation with a fall of 7.46 mm Hg, and psychotherapy with a reduction of 9.83 mm Hg. Combined techniques were associated with a drop of 6.78 mm Hg in blood pressure.

There was no statistical evidence of effectiveness for other treatments assessed at this time point, including biofeedback, progressive muscle relaxation, and techniques involving a combined approach.

The researchers note that the descriptions of relaxation interventions were sometimes incomplete or sparse, there were few data on costs and cost effectiveness, and most of the included studies didn’t report information on the risk of cardiovascular disease/events/deaths.

Reference: Katie E Webster, Monika Halicka, Russell J Bowater, Thomas Parkhouse, Dara Stanescu, Athitya Vel Punniyakotty, Jelena Savović, Alyson Huntley, Sarah Dawson, Christopher E Clark, Rachel Johnson, Julian PT Higgins, Deborah M Caldwell - Effectiveness of stress management and relaxation interventions for management of hypertension and prehypertension: systematic review and network meta-analysis: BMJ Medicine 2025;4:e001098.

Oregon State University researchers have discovered a way to get anti-inflammatory medicine across the blood-brain barrier, opening the door to potential new therapies for a range of conditions, including Alzheimer’s disease, multiple sclerosis, Parkinson’s disease and cancer cachexia. Findings were published today in Advanced Healthcare Materials.

The delivery method involves specially engineered nanoparticles, tiny bits of matter no larger than 100 billionths of a meter. Tested in a mouse model, the dual peptide-functionalized polymeric nanocarriers reached their intended destination, the hypothalamus, and delivered a drug that inhibits a key protein associated with inflammation.

People with cancer cachexia will lose weight even if they eat, and not just fat but muscle mass as well. The debilitating syndrome affects up to 80% of advanced cancer patients and kills as many as 30% of the cancer patients it afflicts.

The systemic delivery of anti-inflammatory agents, including the IRAK4 inhibitors used in this research, to the hypothalamus presents significant challenges, Taratula said, mainly because of the restrictive nature of the blood-brain barrier.

“An additional hurdle, even if you can get through the BBB to the hypothalamus, is hitting the bullseye within the hypothalamus – the activated microglia cells that act as key mediators of inflammation,” said Oleh Taratula, professor in the OSU College of Pharmacy. “Our nanocarriers show a dual-targeting capability, and once in the microglia, drug release is triggered by elevated intracellular glutathione levels. We demonstrated, for the first time, that nanocarriers can successfully deliver an IRAK4 inhibitor to the hypothalamus of mice with cancer cachexia.”

The scientists observed substantial reductions in key inflammatory markers in the hypothalamus, and the nanocarriers led to a 94% increase in food intake and significantly preserved body weight and muscle mass. And the implications extend far beyond cancer cachexia, Taratula added.

Reference: Goo, Y. T., Grigoriev, V., Korzun, T., Sharma, K. S., Singh, P., Taratula, O. R., ... & Taratula, O. Blood‐Brain Barrier‐Penetrating Nanocarriers Enable Microglial‐Specific Drug Delivery in Hypothalamic Neuroinflammation. Advanced Healthcare Materials, 2500521.