ScienceDaily Health

Older adults who received the Shingrix shingles vaccine were 24% less likely to be diagnosed with dementia over four years in a study of more than 500,000 people. Researchers estimate the difference could amount to roughly one dementia case prevented for every 17 people vaccinated.

Researchers have found a way to supercharge natural killer cells, powerful immune cells that can attack cancer, so they can penetrate solid tumors and keep fighting once inside. In mice, these specially prepared tissue-resident cells slowed the growth of several tumors, including melanoma and head and neck cancers, and worked even better when paired with the antibody drug cetuximab.

A major study found that adults with depression show disrupted production of new neurons in the hippocampus, potentially weakening the brain’s ability to separate new experiences from painful memories. The researchers also identified broad molecular changes that could open the door to new treatments tailored to different biological forms of depression.

People who reach 110 and beyond appear to have unusually large numbers of rare immune cells capable of killing abnormal cells. These CD4 cytotoxic T cells became more common with age and often expanded into large groups of nearly identical cells, suggesting the immune system was repeatedly responding to persistent threats.

Common medications may reshape the gut microbiome long after the last dose is taken. In a study of more than 2,500 people, researchers found lasting microbial changes linked not only to antibiotics, but also to antidepressants, beta-blockers, acid-reducing drugs, and benzodiazepines. Some effects were still detectable years later, suggesting past medication use may strongly influence the gut bacteria people carry today.

Backyard bird feeders could become unexpected hotspots for H5N1 as Australia’s bird flu outbreak spreads, bringing species together in ways that rarely occur naturally. Experts say stopping feeding is safest, while smaller amounts of food, no hand-feeding, and careful cleaning can reduce the danger.

Both too little and too much sleep may be linked to faster aging throughout the body. Researchers analyzing 23 biological aging clocks found the lowest aging levels among people sleeping about 6.4 to 7.8 hours per day. Short or long sleep was also associated with numerous conditions affecting the brain, heart, lungs, metabolism, and digestive system.

Gut bacteria can transform nitrate and plant-based iron from vegetables and other foods into protective molecules that may benefit the heart and metabolism. In experimental models, higher levels of these compounds were linked to lower blood pressure, better blood sugar control, healthier blood vessels, and less liver fat.

Researchers have uncovered a possible reason why the Alzheimer’s risk gene APOE4 can disrupt the brain long before memory problems begin. In mice, APOE4 increased a protein called Nell2, shrinking neurons and making memory circuits unusually active. That early hyperactivity predicted worse memory later in life. Reducing Nell2 in adult mice reversed the abnormal changes, raising hopes for a new way to intervene before Alzheimer’s progresses.

Researchers have found a way to slash the processing time for 3D-printed zirconia crowns from as much as 100 hours to under 30 minutes. The advance could eventually let dentists print strong, customized permanent crowns for patients within a single appointment.

Researchers have used AI to uncover the DNA signature of a key genetic “switch” involved in turning genes on. After analyzing about 500,000 DNA sequences, the model identified the initiator in roughly 60% of human genes. The breakthrough could help predict the effects of harmful mutations and eventually contribute to decoding the broader genetic instructions that control gene activity throughout the body.

A decades-old compound may point to a new way of treating obesity by making the body burn more energy rather than simply reducing appetite. In mice, TOFA increased energy use by as much as 18%, reduced body fat without significant muscle loss, and improved blood sugar, triglycerides, and fatty liver disease. It also produced stronger results when combined with GLP-1 drugs such as Ozempic, Wegovy, Mounjaro, and Zepbound.

A massive analysis involving more than 100 million people has found strong links between recreational drug use and stroke, including among younger adults. Cocaine was associated with nearly double the risk of stroke, amphetamines with more than double the risk, and cannabis with a 37% increase.

Older adults with mild cognitive impairment and sleep problems who took at least 5,000 IU of vitamin D daily scored more than 13% higher on a cognitive test than those taking none. The preliminary findings suggest vitamin D could be worth studying as a potentially modifiable factor during an early window of cognitive decline.

Greenland sharks may live for 400 years without suffering the kind of retinal decline normally associated with aging. Researchers found healthy eye tissue and active proteins specially adapted for seeing blue light in the dim Arctic depths. DNA repair mechanisms may help keep their eyes functioning across centuries. The discovery could eventually offer new clues for protecting human vision as we age.

Mice that developed compulsive drinking after alcohol abstinence showed more than double the activity in a brain region associated with stress and addiction. Because the signal appeared before they drank again, researchers think it could eventually help predict who is most at risk of relapse.

Peppermint oil may have an unexpected benefit for people with mildly high blood pressure. Adults who took a small dose twice daily for 20 days saw their systolic blood pressure fall by an average of 8.5 mmHg, while a placebo group showed little change. Researchers say the inexpensive oil could eventually provide a simple additional option for managing elevated blood pressure.

Exercise may not be a powerful weight-loss tool on its own, but it appears to play a much bigger role in preventing lost weight from returning. By preserving muscle, supporting metabolism, improving fat burning, and regulating appetite and blood sugar, regular activity can make long-term weight maintenance easier.

People who speak several languages may have brains that age more slowly, with four-language speakers showing brains that appeared about 13 years younger than those of monolinguals. Starting earlier and becoming highly fluent were also linked to a stronger effect.

A simple yeast-based food supplement may help restore the immune system’s ability to fight cancer, according to new research in mice. Scientists found that yeast beta-glucan reprogrammed early immune cells in the bone marrow, leading to stronger, longer-lasting cancer-fighting responses against colorectal, skin, and breast cancer cells.