CHAPTER 15: Serum Betaine Concentrations and the Effects of Bariatric Surgery

Betaine is a human nutrient present in a variety of foods, rapidly absorbed from intestine, and accumulated in many organs, particularly in the liver and kidneys. Betaine is an important osmolyte, methyl-group donor, and a regulatory molecule. Thus, betaine levels in blood and tissues have a great impact on metabolism, and betaine deficiency could be related to some disorders. Bariatric surgery is the only effective treatment for morbidly obese patients. Unfortunately, bariatric surgery can cause nutritional and metabolic disturbances, due to surgically induced anatomical changes of the gastrointestinal tract. Vitamin B₁₂ and folate deficiencies belong to the common micronutrient deficiencies observed after bariatric surgery. Vitamin B₁₂, folate, and betaine, are involved in methyl group metabolism, including homocysteine to methionine conversion. As betaine and its precursor choline, are obtained from food, and absorbed from the intestine, obese patients may develop betaine deficiency after bariatric surgery. This may lead to disturbances in methylation processes and consequently to hyperhomocysteinemia and related disorders. Monitoring betaine levels and betaine supplementation are therefore essential for treatment and prevention of nutritional and metabolic complications of bariatric surgery. The aim of this chapter is to discuss the pathophysiological role of betaine and its deficiency associated with bariatric surgery.