Higher blood levels of tyrosine, an amino acid widely sold in supplements marketed for focus and brain performance, are linked to a shorter lifespan in men, according to a new analysis of more than 270,000 participants in the UK Biobank. Genetic estimates suggest men with higher tyrosine levels may lose close to a year of life expectancy, the researchers reported in the journal Aging-US. No such link was found in women, who tend to have lower tyrosine levels than men. The study looked at naturally occurring tyrosine in the blood and did not test supplements directly, so the authors say people should not stop eating protein-rich foods, which are the main dietary source of the amino acid.
Blood markers of gut barrier damage begin rising two to three years before a woman's final menstrual period and stay elevated for years afterward, according to a study of 964 women followed for nearly 25 years. Researchers tracked two markers linked to intestinal barrier function: FABP2, which starts rising about 2.5 years before the final period, and sCD14, which rises about 2 years before. Both stabilized six to six and a half years after menopause at levels above their pre-menopause readings. The findings suggest the menopause transition is a long biological process that may help explain the chronic inflammation many women experience in midlife.
The Food and Drug Administration said American Regent is voluntarily recalling three lots of epinephrine injection vials distributed nationwide after customers reported leaking and cracked vials. The company found particulate matter including nylon, cellulose, acrylic, polyethylene and glass in the vials and could not assure their sterility. The recalled product is epinephrine injection USP 30 mg/30 mL (1 mg/mL) multi-dose vials sold under NDC 0517-3030-01, with lot numbers 25128L1C0, 25280L1C0 and 26108L1C0. Epinephrine is used to treat severe allergic reactions and cardiac arrest, so contamination poses a serious risk. American Regent said no adverse events have been reported and is arranging returns and replacements. Customers can call 800-645-1706 for questions.
Older adults who received the Shingrix shingles vaccine were 24 percent less likely to be diagnosed with dementia over four years than those who did not get the shot, a Brown University-led study of more than 500,000 people found. Dementia was diagnosed in 18.8 percent of vaccinated participants versus 24.6 percent of unvaccinated ones, a gap the authors said suggests about one in 17 cases may have been prevented. The study followed adults who entered skilled nursing facilities in the United States. Because it was observational, it cannot prove the vaccine protects the brain. The authors disclosed funding from GlaxoSmithKline, which makes Shingrix, and said the company had no control over the study design or the decision to publish.
Low levels of vitamin B12 and folate in fathers, as well as mothers, around the time of conception are linked to a higher risk of birth defects, a new study finds. Researchers led by Children's Hospital of Fudan University in Shanghai recruited couples planning pregnancy from 29 sites and published the results in Annals of Internal Medicine. Higher B12 before conception was tied to lower birth-defect risk for both parents: moderately high maternal levels were linked to 19 percent lower odds and high levels to 38 percent lower odds. Of more than 400 defects recorded, more than half affected the heart. The findings suggest the protective role of these vitamins reaches beyond neural tube defects.
KRAS inhibitors, a class of drugs already used against some cancers, shrank NF1 nerve tumors in mice at least as well as approved MEK inhibitors, according to a Cincinnati Children's Hospital study published Sept. 2 in the journal Science Advances. Neurofibromatosis type 1 affects about one in 3,000 people, and roughly half develop plexiform neurofibromas, painful nerve tumors that can turn malignant. The research, led by cancer biologist Nancy Ratner, showed that when Schwann cells lose the NF1 gene, the KRAS protein drives tumor formation, making it a clear drug target. Because KRAS inhibitors are already far along in cancer development, the path to testing them in NF1 patients may be shorter.
People who received the newer recombinant shingles vaccine had a 9 percent lower burden of cardiovascular disease over seven years than those given the older live vaccine, according to a study of more than 70,000 older US adults published in Nature Medicine. Researchers at the University of Oxford found the vaccine was linked to a 10 percent lower burden of coronary heart disease and a 12 percent lower burden of heart failure. Men who received the newer vaccine also had a 12 percent lower burden of stroke, and atrial fibrillation was 7 percent lower overall. The benefits appeared in both sexes and were strongest soon after vaccination. Scientists think the vaccine's immune-boosting ingredient may calm inflammation, a driver of heart disease. The study is observational, so it cannot prove cause and effect, but it adds to earlier evidence linking the vaccine to lower dementia risk.
The US Food and Drug Administration has approved Moderna's mRNA-based influenza vaccine, the first of its kind for seasonal flu. The vaccine uses the same messenger RNA technology behind Moderna's COVID-19 shots. In trials, it produced a strong immune response against multiple flu strains, and officials say it can be updated quickly when new strains emerge. The approval gives the United States a second major mRNA vaccine and opens the door to combined flu and COVID shots in the future. Moderna says the vaccine will be available for the next flu season, pending manufacturing and distribution plans. Public health experts say mRNA flu vaccines could improve protection in years when circulating strains differ from those covered by traditional shots.
Two unvaccinated residents of Pennsylvania have died from measles, the first US deaths from the disease in 2026. Both lived in Lancaster County, which has recorded 185 cases this year as part of a statewide outbreak of 393 cases across 28 counties. Nationally, the CDC has counted 2,777 measles cases in 2026, the worst year since 1991. The deaths are Pennsylvania's first from measles in 35 years. Health officials link the resurgence to falling vaccination rates: kindergarten exemptions have more than doubled in five years, from 1.9% to 4%. Measles is highly contagious and fully preventable with the MMR vaccine.
Merck and Moderna say their personalized cancer vaccine has shown promise in preventing melanoma from returning after surgery. In a trial, patients who received the vaccine alongside an immunotherapy drug had a lower rate of recurrence than those on the drug alone. The vaccine is built from the patient's own tumor, teaching the immune system to recognize and attack cancer cells. The companies say they will move to a larger trial and are testing the approach against other tumor types. If the results hold, the vaccine could become a new treatment option for one of the most dangerous forms of skin cancer. Experts urge caution until larger data arrives, but the direction is clear.