This year's stories that made medical headlines can be best described as miracles and meltdowns. What topped 2011's health news was the physical struggle and triumph of one congresswoman as she worked to regain her strength and stamina after she'd been shot in the head, and the psychological struggle of people looking to regain a new sense of national and religious identity after the collapse of some of the world's most ruthless leaders.
Here are the top medical stories reported over this year:
Consumer Confusion: Arsenic in Apple Juice
In less than 24 hours last September, apple juice went from a subject few parents worried about to a source of great anxiety after Dr. Mehmet Oz's comments on "The Dr. Oz Show" regarding the arsenic content in the juice
According to the "Dr. Oz Show's" website, a laboratory tested "three dozen samples from five different brands of apple juice across three American cities" and compared the levels of arsenic to the limits of arsenic for drinking water set by the Environmental Protection Agency. It found 10 samples of juice with arsenic levels higher than the limits for water.
"I don't have any concerns about it in the short run," Oz said. "And the levels that we have detected in the samples that we have looked at are not high enough to make me concerned about short-term issues. My bigger concern is over the next decade or next generation, especially as children grow."
But the claims were not well received by many in the scientific community, including ABC News' chief health and medical editor Dr. Richard Besser. In a spirited showdown hours earlier on "Good Morning America," Besser confronted Oz on what he called "extremely irresponsible" statements.
"Mehmet, I'm very upset about this. I think that this was extremely irresponsible," Besser said. "It reminds me of yelling fire in a movie theater."
"I'm not fear-mongering," Oz responded. "We did our homework on this risk."
In November, Oz's claims proved to hold water. An independent investigation by Consumer Reports into trace amounts of arsenic found in bottled juice prompted Consumers Union, an advocacy arm of Consumer Reports, to urge the U.S. Food and Drug Administration to lower its standards for arsenic levels in juice drinks.
The results of the study, which tested 88 samples of grape and apple juice, found that 10 percent of juices tested had total arsenic levels greater than the Food and Drug Administration's standard for drinking water of 10 parts per billion (ppb), while 25 percent of juices also had lead levels higher than the FDA's bottled water limit of 5 ppb.
Most of the arsenic detected in Consumer Reports' tests was a type known as inorganic, which is considered to be a human carcinogen.
Although federal standards exist for arsenic and lead levels allowed in bottled and drinking water, there are no limits defined for fruit juices.
"Back in September the FDA made a number of statements that reassured me. I'm much less reassured now. They published the test online, but withheld eight results that were very high," Besser said as part of an apology to Oz on "World News."
The testing and analysis led Consumers Union to urge the federal government to establish a standard of 3 ppb for total arsenic and 5 ppb for lead in juice.
Following the report, Besser told "Good Morning America" that parents should limit their children's juice consumption to no more than four to six ounces per day for children under age 7, and no more than 8 to 12 ounces for children older than age 7. Children younger than 6 months should not drink juice at all, Besser said.
Besser also recommended that the FDA do additional testing of juices.
Medical Miracle: Gabrielle Giffords
Rep. Gabrielle Giffords, 40, of Arizona, was likely the medical miracle of the year. Giffords surprisingly survived a gunshot wound to the head and tred a new path to recovery.
In January, Giffords was one of seven shot in January by Jared Lee Loughner, while holding a constituent event outside a Safeway grocery store in Casas Adobes, Ariz. She was later taken to TIRR Memorial Hermann Rehabilitation Hospital in Houston, where she began her long recovery.
Giffords was shot just above her left eye, but the bullet never crossed into the opposite hemisphere of the brain. "This wasn't a little grazing wound through the brain, this was a devastating wound that traveled the entire length of the brain on the left side," said Dr. Peter Rhee, Giffords' trauma surgeon.
A portion of Gabrielle Giffords' skull was removed to ease the stress and pressure on her brain caused by the swelling. The procedure is common in similar brain injuries. In a follow-up procedure, a team led by Dr. Dong Kim inserted a plastic replacement to match the shape of the lost bone.
Depending on the parts of the brain that incurred trauma, injuries often lead to severe impairment in cognition, speech, movement and personality. Typically these injuries can create a host of cognitive and behavioral challenges, from impaired walking to problems with language, attention span and memory.
But that didn't stop Giffords, who was seen in an exclusive ABC News "20/20" special working harder than ever in speech, occupational and physical therapy to regain her language and cognitive skills. Medical experts said her healthy lifestyle could have contributed to her ultimate recovery.
"After severe injury or prolonged disability, patients lose muscle mass, strength and endurance. So when they're up and ready to be mobilized, the more they have left, the better," Dr. Jaime Levine, medical director of brain injury rehabilitation at NYU Langone Medical Center told ABC News. "The more physically agile and fit someone was going into an injury is going to help them throughout the rehabilitation course."
Within two months, Giffords could smile, respond to commands, mouth words to songs and talk on the telephone.
Japan's Nuclear Meltdown
The aftermath of Japan's massive earthquake that spawned a tsunami was felt well beyond central and south Asia. Japan's government ordered thousands of residents living near nuclear power plants in the disaster zones to evacuate the area.
As a result of the disasters, reactors at a nuclear plant in Fukushima began to overheat and leak radiation. Teams of plant workers were deployed to the dangerous site to cool the reactors and prevent a meltdown. Meanwhile, radiation fallout was felt in food and water supplies nearly half a world away.
In response to public fears about radiation from Japan's crippled Fukushima Daiichi nuclear plant, the FDA announced it would stop all milk products and vegetable and fruit products imported from the Japan's prefectures of Fukushima, Ibaraki, Tochigi and Gunma from entering the U.S.
Radiation was also detected in the air or water in 13 U.S. states. But the levels of radiation were far below public health concern, many federal public health experts said.
In December, Prime Minister Yoshihiko Noda of Japan said the Fukushima plant had been stabilized, ending the world's worst nuclear crisis since Chernobyl.
But the fallout remains. Months after containment efforts in Japan, tests of parts of the U.S. water supply in such states as Pennsylvania found abnormally high radiation levels that experts connected to Japan's plants.
Life Saving Drug Shortages
The nationwide hospital drug shortage has been years in the making, but arguably hit a record peak this year. Hospitals have reported the worst shortage in nearly a decade of chemotherapy agents, such as doxorubicin, as well as drugs for heart patients, some antibiotics and intravenous drugs.
Limited manufacturing, lagging production time and low profits for these drugs contribute to the shortages. The production costs for some of these drugs can outweigh the money that companies can earn from making them, especially since many of these drugs now have less-expensive generic alternatives.
The drug shortage has compromised or delayed care for some patients, and may have led to otherwise preventable deaths.
In October, President Obama put drug shortages on the administration's front burner by signing an Executive Order to reduce the dire shortage of lifesaving hospital medications.
The new order instructs the FDA to broaden reporting of potential drug shortages, expedite regulatory reviews that can help prevent shortages and examine whether potential shortages have led to price gouging.
But while the FDA can oversee imports of drugs that are in short supply, it cannot regulate how much a company can make. Manufacturers are not even required to report shortages to the FDA.
The amount of a drug made available within a hospital is set by an agreement between the hospital and the manufacturer.
The Executive Order does not grant new authority to the Department of Health and Human Services or the FDA. Rather, it "advances" and "enhances" the FDA's oversight on a growing shortage of important chemotherapy drugs, anesthetics and antibiotics, Secretary of Health and Human Services Kathleen Sebelius said.
Under the new orders, the FDA will add six people to the five who are assigned to its drug shortage program. The agency will also add two staff members to its Center for Evaluation and Research.
"Obviously, this will put new additional pressures on the FDA in terms of personnel and time demands and financial demands," FDA commissioner Peggy Hamburg said at a news conference before the president's signing. "We will not be able to prevent all future shortages and fully remediate in the near term the existing shortages, but we can make a difference by expanding our net of early warnings and getting in there before the shortage occurs."
Finding Life after Death: From Ruthless Dictators to Top Terrorists
This year brought one of the largest changes of power in generations. Revolutions coined as the Arab Spring forced many Arab leaders to step down or be killed. U.S. military operations brought down the FBI's -- and perhaps the world's -- most wanted.
For many families who have endured generations of pain at the hands of these leaders, the end of the year can bring feelings of closure and hope for a new beginning.
This year's news of Osama bin Laden's death and burial at sea brought mixed feelings for families who lost loved ones on 9/11 -- relief that the world's most notorious terrorist has been brought to justice but also a reminder of the pain they felt nearly a decade ago.
While it may seem as if jubilation and grief are distinct sentiments, many psychologists and psychiatrists say these mixed emotions are painful indicators that define feelings of long-awaited closure.
"Closure does not necessarily mean no longer feeling grief, or no longer feeling angst or pain over a situation," Dr. Alan Hilfer, chief psychologist at Maimonides Medical Center in New York told ABC News at the time. "It means essentially having threads of resolve."
But many find peace of mind by allowing themselves to understand that they may never stop feeling a sense of loss, Hilfer said.
The intensity of bereavement wanes over time, said Dr. Howard Belkin, assistant professor of psychiatry at William Beaumont Hospital in Royal Oak, Mich.
In May, ABCNews.com interviewed Abigail Carter, 45, whose husband, Arron, was killed in the World Trade Center on 9/11. She said she did not need news of Osama bin Laden's death to feel closure.
"For me to close a chapter, I don't need vengeance. For me, closure comes from within," said Carter, who wrote, "The Alchemy of Loss: A Young Widow's Transformation."
But for others around the world who have endured a loss, the very public death announcements that represent a shift of world's power may bring on different sentiments associated with grief and closure.
ABC News' Carrie Gann and Kim Carollo contributed to this report.