NEW YORK — A second wave of seasonal influenza is taking hold in the U.S., just as health officials are on high alert for new cases of the novel coronavirus. Many of the symptoms are the same, but when it comes to immediate risk, Americans should fear the flu more.

CAMBRIDGE, Mass. — Biogen said on Thursday it was preparing for the launch of its experimental treatment for Alzheimer’s as the drugmaker races to become the first to bring a treatment for the memory-robbing disease to market.

Most people know that high cholesterol is bad for their heart, but few people really understand what cholesterol is. Dr. Claire Haga, a Mayo Clinic family physician, explains why it’s so closely related to heart problems. She also discusses the power you have to control it.

Many people dread the dark days of winter. Having to spend time indoors can bring on the blues, and close quarters can increase the risk of catching a cold or flu. Dr. Brent Bauer, a Mayo Clinic internal medicine specialist, has tips to help you have a healthier winter.

SEATTLE — When Dr. Judith Tsui moved from Boston to Seattle five years ago, she immediately recognized something she didn’t see much back East: People seeking treatment for opioid use disorder were also using methamphetamine.

You’re not doomed to toss and turn every night. Consider simple tips for better sleep, from setting a sleep schedule to including physical activity in your daily routine.

Kids exposed to air pollution in the womb may have higher blood sugar levels during childhood than kids without this exposure, according to a study that suggests particle pollution could be an environmental risk factor for diabetes.

A study published in the Journal of the American Heart Association indicates there may be a link between binge drinking and heavy alcohol consumption and heart damage.

Screening fathers for postpartum depression is as important as screening mothers, researchers argue, and current guidelines don't go far enough in urging doctors to identify new fathers who may be suffering.

At this time of year, cold and flu season mixes with holiday shopping, parties and travel. That means extra opportunities to share holiday cheer — and germs and viruses. However, you may be surprised by how germ-filled common objects and places are that you encounter every day along the way.

Q: My mother has been diagnosed with Alzheimer’s disease, but she seems to be declining rapidly. Doesn’t Alzheimer’s usually get worse slowly?

Roughly half of middle-aged Americans believe they’re “somewhat” or “very likely” to develop dementia, a survey suggests, and many try to beat the odds with supplements like ginkgo biloba and vitamin E that aren’t proven to help.

A lot of time and effort goes into making a holiday meal. Tables will overflow with family favorites and traditional dishes such as candied yams and green bean casserole.

CHICAGO — Tests of lung samples taken from 29 patients with vaping-related lung injuries suggest all contained Vitamin E acetate, a discovery U.S. officials described as a “breakthrough” in the investigation of the nationwide outbreak that topped 2,000 cases this week.

PHOENIX — As fall and winter sports are in full swing, youth athletics will see a rise in injuries. Tens of millions of children and teens participate in organized sports, and more than 3.5 million sports injuries occur every year.

Dear Mayo Clinic: For the past few weeks, my 13-year-old daughter has had trouble falling asleep at night. She’s in bed at a reasonable time, but can’t seem to fall asleep until after midnight. What could cause insomnia in someone so young? Should I make an appointment for her see her doctor?

Women who go through menopause earlier in life may be more likely to have a heart attack or stroke before they reach age 60 than their counterparts who go through menopause later on, a recent study suggests.

CHICAGO — U.S. health officials this week reported another 180 cases of vaping-related lung illnesses and announced plans to start testing aerosols produced by e-cigarettes and vaping products as they search for the source of the nationwide outbreak that has so far killed at least 33 people …

Low-risk pregnant women who deliver in a hospital and receive care from midwives have fewer interventions and fewer cesarean sections than similar women who receive care from obstetricians, a U.S. study finds.

People with a positive outlook on life may be less likely than pessimists to experience events like a heart attack or stroke, and they may live longer, a recent review of existing research suggests.