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Taking 2,000 International Units of supplemental vitamin D₃ daily may help slow the cellular aging process, according to a 2025 study.

Havard researchers have identified biomarkers that appear to capture tinnitus severity for the first time. Scientists made the connection after analyzing the facial responses and pupil dilation of study participants as they listened to pleasant, neutral, or unpleasant sounds. The findings, when fed to a computer model, accurately predicted the severity of symptoms participants had reported on questionnaires. Scientists hope the biomarkers will lead to tools that gauge tinnitus severity and treatment effectiveness.

Two kinds of migraine involve visual disturbances, such as strange, flickering light patterns. One type is migraine with aura, caused by brain activity. The other is ocular migraine, caused by blood vessel problems in the eye. The attacks may or may not be accompanied by a headache. Drugs called triptans might help soothe migraine with aura. Doctors don’t have a way to stop an ocular migraine attack as it’s occurring. For many people, the only way to cope is resting and waiting until the symptoms go away.

A 2025 randomized controlled trial found that GLP-1 receptor agonists, the blockbuster drugs approved to treat diabetes and obesity, boosted the walking ability of people with diabetes and peripheral artery disease (PAD) in the legs. The news is encouraging, since there are few effective treatments for PAD—reduced blood flow in the limbs that leads to pain with activity. However, it will take more evidence before doctors feel comfortable prescribing GLP-1s if a person only has PAD.

In robotic surgery, a surgeon controls robotic instruments that perform the operation, based on what the surgeon sees on a TV monitor. This type of surgery has many advantages: it involves small incisions, better views inside the body, and better range of motion than human hands. A research letter published in the May 2025 issue of JAMA Neurology described how robots controlled by a distant surgeon could reach in, grab, and remove blood clots stuck in a brain artery, reducing the damage from a stroke.

The four types of anesthesia include local anesthesia, regional anesthesia, monitored anesthesia, and general anesthesia. Before getting anesthesia, one should ask the doctor which type of anesthesia will be administered, what its risks are, and if delirium is a high risk. One should also ask how to prepare for anesthesia in the days leading up to a procedure—whether medications might need to be temporarily halted, when to stop eating or drinking before surgery, and whether to schedule measures to help reduce delirium.

In a 2025 study, people with the healthiest diets and trimmest bellies at midlife had better brain connections and skills decades later, compared with people who ate the worst diets and had the most belly fat.

In a 2025 study of about 900 people treated for colon cancer (followed for an average of eight years), people who took part in a supervised exercise program for three years had about 30% better odds of surviving, compared with people who weren’t in the program.

In a 2025 study of more than 420,000 participants followed for about 13 years, people who walked at a steady or brisk pace had up to a 43% lower risk for developing heart arrhythmias, compared with those who walked at a slow pace.

Hand therapy is an effective way to overcome lost hand function due to injuries or underlying conditions. A course of therapy typically lasts for six weeks. It involves working with a certified hand therapist (CHT) who can develop and then guide someone through a tailored program of physical and functional exercises. CHTs also can make splints, offer emotional support, and help people learn to manage hand pain and swelling. It’s best to start hand therapy before an injured hand has healed completely.