The U.S. Preventive Services Task Force asked doctors last year to stop checking PSA levels in elderly men—the very men who are most likely to have prostate cancer. By age 75, the officials reasoned, doctors are more likely to keep tinkering with their patients until they die of treatment side effects or something other than prostate cancer altogether. This spring, the New England Journal of Medicine published two long-term studies that questioned whether knowing a man's PSA level actually helps men survive. Healthcare commentators say that PSAs set off a cascade of overtreatment, endangering patients and tolerating wasteful medicine, and that patients should be wary.

You might expect that the surgical specialists at the center of prostate cancer treatment would have reined in their PSA testing, but they haven't. The American Urological Association actually lowered its recommendation for the age at which doctors should start offering patients the PSA test from 50 to 40. It was the first revision of the guidelines in nearly a decade. The next one, says Kirsten Greene, a urologist who worked on the committee, should take just a year, in light of the accelerating data and heightened public debate.

"The key change is how we react to abnormal tests and to a cancer diagnosis, which is generally less aggressively for some men than in the past," says Gerald Andriole, chief of urologic surgery at Barnes-Jewish Hospital/Washington University School of Medicine in St. Louis. Andriole says that men shouldn't be afraid to get diagnosed; good urologists avoid overtreating less-dangerous cancers. Active surveillance or targeted attacks on very small tumors that spare healthy prostate tissue are both popular options.

Bisphenol-A, better known as BPA, is the building block of polycarbonates and epoxy resins, plastics that have facilitated modern life. (They're in microwave containers, baby bottles, laptops, and even canned foods.) Tiny amounts circulate in the bodies of more than 90 percent of Americans. And now a team of Chinese and U.S. scientists says it has linked the stuff to sexual dysfunction in men. Even before today's news, plenty of people were getting the willies about BPA. Should this news make you feel less virile? Let's take a closer look.

Six years ago, De-Kun Li, a senior scientist at Kaiser Permanente's research arm, and his colleagues were already alarmed about BPA because of a steady stream of studies showing that BPA alters tissues in the reproductive organs and offspring of rats and mice. But there's a heated debate among statisticians, toxicologists, and endocrinologists about which animal models are relevant to human disease and about the paradoxical way BPA seems to work. Unlike typical poisons or carcinogens, more is not always worse and less is not always better. In many of the studies, BPA changes animal tissues only at specific low concentrations and only at particular stages of the life cycle.

Some 35,000 men who participated in a major prostate cancer prevention trial are in the process of getting this disheartening—yet not entirely surprising—letter in the mail from the National Cancer Institute. The message: Vitamin E and selenium, long buzzed about for their supposed prostate cancer-fighting properties, have flopped. Flopped hard.

Officials announced this week that they had accumulated enough data to conclude that taking vitamin E or selenium, or even both together, does not prevent prostate cancer. In fact, vitamin E may even slightly increase the risk. Leaders of the trial, called the Selenium and Vitamin E Cancer Prevention Trial, were also concerned to find that slightly more cases of diabetes arose among men who took selenium. And though officials emphasized to reporters that the increased number of prostate cancer and diabetes cases may have been a coincidence, they aren't taking any chances. That's why participants are being told to stop taking the supplements.

While many websites sell drugs online illegally, one company called KwikMed offers consumers the option of buying certain medications—the erectile dysfunction drugs Cialis, Viagra, Levitra; the hair loss drug Propecia; and the smoking cessation—without ever seeing a doctor face to face. Though KwikMed hopes to offer additional drugs in the future, these five drugs are the only ones that have been approved by regulators to date. And it's all perfectly legal, the company says—though quite unusual. The arrangement that KwikMed has reached with the Utah Legislature allows the company's doctors to offer valid prescriptions through cyberspace; other states require that patients see a doctor in person, KwikMed says, before they can receive a prescription. Still, even if you don't live in Utah, you can probably order KwikMed's drugs. The company has received mail order licenses from many other states, and it has shipped medications to 46 states so far. A preliminary study of KwikMed (led by an independent researcher but including a company employee as a coauthor), published recently in Mayo Clinic Proceedings, shows the system is just as safe as having in-the-flesh primary physicians examine patients and prescribe erectile drugs.

Since I've written before about men's propensity for taking risks and have spent a fair amount of time poring over government statistics that show which types of accidents are most lethal for men, I thought I'd pretty much considered all the bizarre ways we end up offing ourselves.

Then I ran across this release from the Centers for Disease Control and Prevention about car surfing. Yup, you read that right: car surfing, which the CDC defines as a "thrill-seeking activity that involves riding on the exterior of a moving motor vehicle while it is being driven by another person." Men were the victims of car surfing accidents in 70 percent of the cases. The feds, apparently, got the idea of looking into the phenomenon of car surfing after watching clips like this one on video sharing sites.

While doctors once steered people with type 1 diabetes away from vigorous exercise, the development of new monitoring and insulin delivery technology has prompted them to change their tune. "The sky is the limit. From an athletic perspective, there's no type of exercise a person shouldn't do, as long as they're willing to monitor and manage their diabetes," say Larry Deeb, past president of medicine and science for the American Diabetes Association. Previously, doctors warned that sudden uncontrolled dips in blood sugar levels that often accompany intense exercise could cause fainting, seizures, and even comas.

It isn't clear whether circumcision protects gay men from infection with the HIV/AIDS virus as it does heterosexual men, a study released this week says. Previous research has shown that circumcision lowers rates of AIDS infection by some 50 to 60 percent among heterosexuals. So there's nothing from this research that men—gay or straight—can or should act upon at this point. The science simply isn't reliable enough at this point to say, for example, whether uncircumcised men would benefit from running off and getting the procedure.

But here's what we do know about gay men and HIV in the United States:

• 53 percent of all new HIV/AIDS cases involve gay men, according to the CDC.

• 71 percent of all new HIV/AIDS cases in male adults and adolescents involve gay men.

• New cases of HIV are increasing faster among gay and bisexual men than other demographic groups, particularly among gay black men.

• Practicing safe sex offers protection.