Obesity has been linked to numerous health problems, from heart disease and diabetes to arthritis and stroke. Now, asthma and aggressive prostate cancer can be added to the list. With such grim prognoses, many obese patients are choosing to undergo bariatric (weight-loss) surgery to shed pounds and reduce the risk to their health. Gastric bypass, the most common type of bariatric surgery, involves either stapling or removing part of the stomach to reduce the amount of food that can be eaten and absorbed by the patient's body. A study published in January found that gastric surgery may increase life expectancy for morbidly obese patients. However, according to the Mayo Clinic, gastric bypass surgery carries risks such as bleeding, infection and death, along with potential complications such as gallstones, hernia at the incision site, nutrient deficiency, and dehydration. A new study suggests that patients who undergo the surgery have an increased risk of developing kidney stones. As with any invasive surgical procedure, gastric bypass surgery is traumatic to the body and requires a longer recovery time than minimally invasive procedures. A number of companies are developing minimally invasive devices that produce the weight-reducing effects of a gastric bypass minus the actual surgery. Some companies in this space include the following: Endosphere has developed a platform of implantable devices for metabolic disorders. The devices are designed to boost the activity of the duodenum, which regulates appetite and glucose production. As a result, food may pass through the duodenum more slowly, and the patient may feel full sooner. Causing food to slow its passage through the gastrointestinal system is known to aid in weight loss by reducing the patient's appetite. Endosphere is conducting clinicial trials in Europe. GI Dynamics’ Endobarrier Gastrointestinal Liner is designed to mimic the effects of bariatric surgery. The implantable device keeps is placed along the wall of the small intestine to keep food from coming in contact with the intestine wall, which clinicians believe affects hormonal signals related to appetite. BAROnova, creator of the TransPyloric Shuttle (TPS) weight-loss system. The device has the potential to slow gastric emptying. According to the company’s website, the device has been tested in humans with positive results. In 2008, the company secured an investment from Allergan. Satiety is testing a series of devices that staple the stomach, as in gastric bypass surgery. However, these devices are inserted through the mouth, eliminating the need for surgical incisions. The company expects primary completion of the TOGA trial in October 2010. IntraPace is developing a “gastric pacemaker” that can be implanted in a laparoscopic procedure. When the “abiliti” system detects that the patient has consumed food or drink, it emits a series of low-energy electrical impulses designed to create a feeling of fullness. What are some other innovative weight-loss devices you've heard about? Feel free to share in comments.