Teens and Weight Loss Surgery: Worth the Risk?

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Teens who undergo weight loss surgery such as a gastric bypass may suffer loss of bone mass, say researchers.

As recently published in Pediatrics, a study which followed 61 obese teens who were subjected to gastric bypass surgery found that two years later, teens’ bone mineral content had decreased by over 7%.

Gastric bypass surgery involves reducing the stomach from the approximate size of a football to that of a golf ball by essentially pinching the stomach to size. Some common side effects of gastric bypass surgery include low bone mineral density, as well as vitamin B12 deficiency.

Gastric Bypass Surgery and Vitamin B12 Deficiency

The study was led by Dr.  Anne-Marie Kaulfers, assistant professor of pediatrics at the University of South Alabama.  Dr. Kaulfers and her team were concerned about the future bone health of obese teens who undergo bariatric surgery; the adolescents included in this study had better than average bone mineral density before the surgery, but Kaulfers hopes  to track their bone health into adulthood.

Loss of bone mass is typical for patients of weight loss surgery, in adults as well as teens.

The study was conducted at the Children’s Hospital Medical Center in Cincinnati, and was part of their Teen-Longitudinal Assessment of Bariatric Surgery Consortium program.

  • The teenage study participants included 51 girls and 10 boys who underwent gastric bypass surgery.
  • In most cases, bone mass density was measured before each surgery and every 3-6 months thereafter for 2 years.
  • Bone mineral density “z scores” resulted in a decrease from 1.5 to 0.1, a normal z score being 0.  Low bone density would result in a negative score, explains Dr. Kaulfers.
  • Scientists theorize that the bone loss could be a result of the actual weight loss itself, or could signal some hormonal changes taking place.

While the possibility of suffering low bone mineral density is a troubling one, researchers believe that the benefits of weight loss surgery, such as diabetes prevention, outweigh any negative side effects.

Vitamin B12 deficiency is another common side effect of gastric bypass surgery, as patients who undergo bariatric surgery have insufficient stomach acids to digest vitamin B12 properly.  Physicians strongly recommend that anyone who subjects himself to weight loss surgery and is diagnosed with low B12 supplement with vitamin B12.

Also read Gastric Bypass Surgery: Good for the Heart


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