THURSDAY, Dec. 29 (HealthDay News) -- While no one story dominated health news in 2011, the ongoing debate over the legality of the new health care reform law was perhaps the most polarizing, with the case now set to go to the U.S. Supreme Court early in 2012.

Supporters of the Patient Protection and Affordable Care Act, which President Obama signed into law in 2010, claim the legislation will extend coverage to 30 million Americans. But opponents labeled it an unconstitutional intrusion of government upon personal rights, especially the "individual mandate" clause that requires Americans to purchase health insurance or face fines.

Some of the law's provisions, such as allowing children to remain on their parents' plans until age 26, or prohibiting insurers from denying coverage to those with preexisting conditions, were already helping Americans in 2011. Still, a Harris Interactive/HealthDay poll conducted in March found just 22 percent of respondents supported the individual mandate clause. The U.S. Supreme Court will begin hearing arguments on the law in late March.

Feel like chatting about the issue on your cellphone? That brought up another top health concern for 2011: Do the electromagnetic fields emitted by the phones cause cancer, or don't they. In February, an analysis of 10 years of British data found no uptick in brain cancer rates even as more people were using cellphones; and in July, Swiss researchers reported in the Journal of the National Cancer Institute that they could find no link between cellphones and brain tumors in kids.

However, in late May, a panel of experts at the World Health Organization announced that they were classifying cellphones as "possibly carcinogenic to humans," putting the devices in the same category as the pesticide DDT and gas engine exhaust. In the meantime, experts are supporting using cellphones -- but perhaps with an earpiece or speaker, away from the head.

There was more confusion on the cancer-screening front, as well, with the United States Preventive Services Task Force's recommendation in October against the use of the prostate-specific antigen (PSA) blood screen for men at average risk for prostate cancer.

Debate had raged for years over whether the PSA test was a useful tool to spot cancers, or whether too many men were now getting unnecessarily treated for slow-growing tumors that might never harm them.

Based on results from two major studies, the panel agreed with the latter argument. "This test cannot tell the difference between cancers that will and will not affect a man during his natural lifetime," panel chairwoman Dr. Virginia Moyer, told The New York Times.

Tobacco companies also took a hit in 2011, with the U.S. Food and Drug Administration proposing graphic new cigarette-pack labeling, including photos of ill patients breathing through tracheotomy tubes, or ulcerated lips and mouths.

While such labeling has cut into smoking rates in other countries, it's unclear whether they'll ever appear in the United States: in November, a federal judge blocked the labels, saying their message crossed too far into advocacy. The Obama Administration has since appealed that decision.

Other health news highlights from the past year, as determined by the editors at HealthDay:

• An outbreak of deadly listeria linked to tainted cantaloupes killed 30 people and sickened 146 more across the country earlier this fall; health officials blamed the outbreak on unsanitary conditions at the Colorado company that produced the fruit.
• In February, a study reported in the Journal of the American Medical Association suggested that women with early breast cancer may not require the extensive removal of lymph nodes that often follows lumpectomy and radiation. Lymph node removal can cause a debilitating swelling of the arms known as lymphedema.
• The trend among a minority of U.S. parents to forgo vaccinating their children against common infectious diseases continued. This summer, a survey from the U.S. Centers for Disease Control and Prevention (CDC) found that about 5 percent of parents had declined some vaccines for their kids, even though an exhaustive Institute of Medicine report released in August found pediatric shots to be safe.
• There was very good news in the fight against HIV/AIDS: research published in 2011 helped confirm that treating infected individuals with powerful drugs could dramatically cut transmission rates to partners. At the same time, advances in gene therapy and other means of beating back HIV to undetectable levels had some experts cautiously expressing hopes for a cure.
• News from the battle against the leading cause of deaths due to cancer, lung cancer, was also encouraging. In June, updated data from a U.S. National Cancer Institute trial suggested that routine CT chest scans might cut the death rate by 20 percent for former or current smokers. And in September, the CDC announced another milestone: the first-ever decline in deaths among women from the disease, as fewer women decide to smoke.