Gastric bypass surgery, which helps people to lose large amounts of weight by reducing the absorption of calories, may also result in loss of bone mass, according to a study.

In the surgery, doctors staple off a section of the stomach so that it can only hold a small amount of food and add a bypass that allows food to go around part of the small intestine, limiting the absorption of calories.

The study involved 27 patients who had the Roux-en-Y gastric bypass surgery and another 29 people who were awaiting the procedure. Patients who had had the surgery lost an average of 80 to 100 pounds after 10 months.

However, according to urine and blood tests, they were also breaking down bone faster than it was rebuilt. The more weight lost, the faster the rate of bone breakdown, researchers said.

Patients awaiting surgery were breaking down and rebuilding bone at normal rates. The bone breakdown rate of those who had had the surgery was about twice the rate of those who did not have the surgery.

Researchers are not certain why this effect is occurring, but suggest that the surgery may decrease calcium absorption. Another potential explanation is that the patients’ excess body weight may have been strengthening bones as lifting weights strengthens bones. Therefore, when the excess weight is removed the bones have to adjust to the reduction in weight.

Researchers plan to continue studies to determine whether the findings lead to a loss of bone over time that could put patients at risk of osteoporosis. They note that patients should have their bone density measured every couple of years.

Annual Experimental Biology meeting San Diego April 13, 2003

Dr. Mercola's Comments:

Gastric bypass surgery is the only approach that traditional medicine has for obesity. Its long-term success rate borders on 10 percent and is fraught with other complications aside from bone loss. One of the severe side effects of intestinal bypass surgery is liver failure. This is a long-term side effect and doesn't show up until about 10 years postoperative in most patients. Combined with the liver failure is damage to the immune system, and most patients who exhibit the symptoms of liver failure also show evidence of autoimmune disease as well. It just doesn’t make much sense to go on a forced low-calorie diet that in no way, shape or form solves the cause of the problem. Many times the low-calorie approach will trigger a starvation response and lower the rate at which you use calories. Needless to say, I am not an advocate of this approach when far more effective, healthy and less expensive options exist. The primary one is a low-grain diet that is discussed in my new book, The No-Grain Diet. I do have a number of patients who have had the procedure done (not with my recommendation) and have lost over 100 pounds. It is important to understand that if you have had this surgery done you are at high risk of bone loss. This is quite clear as there are many other studies documenting this association. Consuming raw dairy products would clearly be a helpful strategy at combating this bone loss, as it is without question the best calcium supplement one can obtain. Optimizing your vitamin D levels would also be wise, as you need vitamin D to facilitate absorption of the calcium into the blood. Related Articles: Bony Vegetables