These breakthroughs range from making body parts on a 3D printer to getting the body to fight cancer on its own

The big health care story of the past six months has been the bumbling signup process for insurance coverage under the Affordable Care Act. But plenty of advances in medical research and treatment were made last year that could start to have a big impact in 2014.

Here are seven to watch:

1) You never have to worry about toner: People can get a little giddy about 3D printers, how it won't be long before kids are using them to crank out their personally-designed toys and the rest of us are making our own shoes. We'll see about that. But medical researchers have already turned to 3D printing to create human body parts and they're just getting started.

Last year Cornell scientists printed out an artificial outer ear that looks and works like the real thing. Meanwhile, researchers at the University of Pennsylvania and M.I.T. have used printers to produce blood vessels, while scientists at Wake Forest have developed a way to print skin cells directly on to wounds. Now, a San Diego company named Organovo says it will print a human liver this year. The artificial organ would be used only in a lab for drug research--it wouldn't be suitable to implant in a human--but it's more evidence that human tissue from a printer can be kept alive.

2) A lean, mean gene machine: Gene therapy, in which a person's genes are re-engineered to fight diseases and put back into his or her body, is still considered experimental, but it's been effective recently in treating patients with leukemia and other blood cancers. And, a study published last week found that the technique actually reversed breast cancer development in mice, raising hope that one day it could become a new way to treat early stages of the disease without resorting to surgery, chemotherapy or radiation.

3) Gut reactions: Another area of research showing a lot of promise has to do with our guts, specifically all the bacteria residing there. Among the more recent findings: That there may be a direct physiological connection between the mix of microbes in our digestive tract and how our brain functions, and that that mix can also be a factor in whether a person is thin or obese.

Expect more focus this year on how gut bacteria affect not just gastrointestinal diseases, such as ulcerative colitis and Crohn's disease, but also cancer and allergies. In fact, a study just published in the Proceedings of the National Academy of Sciences determined that when dust from houses in which dogs lived was introduced into the gut bacteria of mice, the lab animals were less likely to develop symptoms of asthma.

4) Take that, cancer!: The War on Cancer has been going on a long time, with its share of false hopes, but a growing number of experts suggest that the fight may have turned a corner with a treatment known as cancer immunotherapy. Last month, for instance, Science magazine named it the "Breakthrough of the Year."

So what exactly is cancer immunotherapy? Put simply, it is using drugs that spur the body's immune system to battle tumor cells directly. The reason this doesn't happen naturally, as researchers discovered a few years ago, is that tumor cells are able to wrap themselves in a protective shield. But new drugs are being tested that have been able to empower the immune system to break through that protection and allow the body to do its job in fighting cancer cells on its own. The number of cases where immunotherapy has been tested is still relatively small, but the results have been encouraging. And, as Jennifer Couzin-Frankel wrote inScience, "Immunotherapy marks an entirely different way of treating cancer—by targeting the immune system, not the tumor itself."

5) Behold the bionic eye: Add another body part to the bionic human. Last year, a California company named Second Sight received FDA approval to begin marketing a bionic eye it has developed. A tiny camera in a patient's glasses captures images that are converted into electrical pulses, which are then transmitted wirelessly to an antenna in a retinal implant--that allows it to bypass the damaged part of the retina. The pulses are transmitted by the optic nerve to the brain, which interprets the images and creates patterns of light. This doesn't restore what would be considered normal vision, but it allows people with the disorderretinitis pigmentosa to identify objects, and even perceive color. Researchers believe that these types of implants may one day be able to restore some level of sight to people with macular degeneration, the leading cause of blindness in the U.S.

6) Replacing a face: The first full face transplant was done only three years ago and the surgery is still extremely rare, but new research is likely to make surgeons more confident about undertaking a procedure that seemed impossible a decade ago. Scientists analyzed three people who have received face transplants and discovered that blood vessels actually reorganize themselves in the patients' faces and grow back towards their ears. Knowing that, according to the study's authors, can help surgeons not only shorten how long the complex operation takes, but also reduce potential complications.

Meanwhile, the U.S. government now is working on regulations for how people would be able to opt in as potential donors for face and hand transplants after they die. Those regs, expected to be released this summer, will undoubtedly distinguish consent requirements for face transplants from those for other organs. Transplantation experts say that fewer next-of-kin are likely to consent to donation of their loved ones' faces, and they don't want that to discourage donations of other organs.

7) But when will there be an app that counts Doritos?: If there's any doubt that wearable devices that track our health are going mainstream, consider this: When the Consumer Electronics Show (CES) kicks off in Las Vegas later this week, companies showing off digital health devices will take up 40 percent more exhibit space than they did last year.

There already are plenty of gadgets and apps out there that track your steps, your sleep and and your calorie consumption and generally let you know how you're doing. But the next wave of wearable health tech will focus on gathering personal data more meaningful to a doctor, and send it directly to his or her office--such as a remote stethoscope that can transmit a person's heart rhythm to a physician.

Also, devices that monitor our personal behavior will be getting more and more sophisticated. There's the AIRO wristband—hitting the market later this year—that will use a built-in spectrometer to detect nutrients released into your bloodstream as they are broken down during and after your meals. A device being developed by TellSpec will supposedly be able to analyze the chemical composition of food in real time and let you know on your smartphone just what it is you're about to eat.

Video bonus: Here's more on the printing of "robo-hands" and artificial ears.

Source: http://www.smithsonianmag.com/innovation/7-medical-advances-to-watch-in-2014-180948286/