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- Ketogenic diet, by replacing glucose with ketones as an energy source, lessens alcohol cravings among people with alcohol use disorders.
- Omega-3 fatty acids reduce the risk of cardiovascular disease-related death by up to 23 percent, especially in people with high triglyceride levels.
- Women see a 24 percent drop in premature death risk with just 140 minutes of weekly activity – half the time men need for similar benefits.
- Aging undermines the brain's capacity for maintaining working memory, with subtle declines in neuron activity and connectivity in the prefrontal cortex.
Nanoplastics are emerging as a new concern in environmental and human health due to their capacity to interact with biological systems at the cellular level. Their small size allows them to penetrate tissues and potentially disrupt key physiological processes, particularly in the gut. A recent study in mice found that polystyrene nanoplastics can disrupt gut bacteria, weaken the intestinal barrier, and trigger molecular changes that may have far-reaching effects on health.
Researchers exposed mice to oral doses of polystyrene nanoplastics four times a week for 12 weeks and used fluorescent labels to track where the particles went. Then, they examined the animals' gut tissue, analyzed changes in their gut microbiota, and evaluated changes in extracellular vesicles—tiny membrane-bound structures released by gut cells and bacteria that facilitate intercellular communication.
The researchers found that nanoplastics accumulated in the gut, liver, and other tissues for up to 48 hours. Mice exposed to nanoplastics gained more weight than unexposed mice—about 28% more—despite no differences in liver or fat tissue mass. Nanoplastic exposure altered gut microbial populations, disrupted mucus production, and interfered with proteins maintaining the gut barrier.
These findings suggest that nanoplastics weaken the gut’s defenses by altering the microbiome and changing how gut cells communicate through extracellular vesicles. Over time, this disruption could increase vulnerability to disease, even without obvious inflammation or liver damage. Learn more about micro- and nanoplastics in our overview article.
Immersing sore muscles in hot or cold water is a common recovery practice among athletes and other active people. However, most research on its effects has focused primarily on men, leaving women underrepresented in this area of study. A recent study found that neither hot nor cold water immersion improved muscle recovery in women after intense exercise.
Researchers asked 30 healthy young women to complete a demanding jumping workout to induce muscle soreness and temporary muscle damage. Immediately after the workout, and again two hours later, participants sat in cold, hot, or no water for 10 minutes. The researchers then monitored changes in muscle soreness, strength, swelling, and levels of creatine kinase, a marker of muscle damage, over the following three days. They also tracked muscle oxygen levels, core temperature, skin temperature, and heart rate.
Cold water immersion reduced muscle oxygen levels, decreased skin temperature, and lowered core temperature compared to hot water or no immersion. In contrast, hot water immersion increased both skin and core temperatures. However, despite these distinct physiological differences, none of the groups experienced faster recovery than the others. Additionally, hot water immersion promoted slightly more muscle swelling and higher creatine kinase levels at specific time points.
These findings suggest that while hot and cold-water immersion alters the body’s short-term response, they don’t accelerate recovery in women after muscle-damaging exercise. However, cold exposure may have other health benefits, such as enhanced immune function. Learn more in our overview article.
The glymphatic system—the brain’s waste clearance network—uses cerebrospinal fluid to flush out toxic metabolic byproducts, including amyloid-beta, tau, and other protein aggregates. This clearance process plays a critical role in maintaining brain health and may help protect against neurodegenerative diseases, such as Alzheimer’s. A recent study in mice found that a network of lymphatic vessels in the neck aids glymphatic waste removal, and this system can be enhanced using a gentle, non-invasive technique.
Researchers viewed the lymphatic vessel function of mice using fluorescent tracers. They tracked how cerebrospinal fluid drained from spaces around the brain into lymphatic vessels near the base of the skull and then flowed through tissues near the eyes, nose, and mouth into superficial lymphatic vessels in the neck. Then, using a small mechanical device, they gently compressed the animals' skin in three areas: from around the eyes down to the jaw; from the side of the nose down to the jaw; and along specific lymphatic vessels leading to a lymph node under the jaw.
They found that about half of the cerebrospinal fluid outflow to the neck passed through the superficial lymphatic vessels. Older mice had fewer lymphatic vessels near the nose and roof of the mouth and exhibited reduced cerebrospinal fluid clearance. However, the lymphatics in the neck remained structurally intact and responsive to stimulation. When they applied the mechanical device to the skin, cerebrospinal outflow doubled, even in aged mice.
These findings suggest that poor glymphatic waste clearance in aging may be reversible by stimulating functional lymphatic vessels in the face. If this approach works in humans, it could offer a simple, noninvasive strategy to support brain health and reduce the risk of neurodegenerative disease. Deep sleep also promotes glymphatic clearance. Learn more in this clip featuring Dr. Matt Walker.
