Vitamin B12 is the largest and most structurally complex vitamin. B12, otherwise known as Cobalamin, is one of the most common vitamin deficiencies amongst gastric bypass surgery and sleeve gastrectomy patients. The absorption of vitamin B12 begins in the mouth, tiny amounts of particles are absorbed through mucous membranes. Vitamin B12 is an important nutrient that the human body needs to keep the nerve and blood cells healthy, the vitamin also assists in making DNA, the genetic material in all cells. B12 also assists in the prevention of megaloblastic anaemia that causes people to become tired and weak.

Intrinsic factor is a glycoprotein secreted by parietal cells of the gastric mucosa, its main responsibility is to absorb vitamin B12 within the intestine, failure to produce or utilise intrinsic factor within the human body can result in B12 deficiency. The portion of the stomach that is responsible for making intrinsic factor is bypassed during laparoscopic gastric bypass surgery or excised in sleeve gastrectomy. This leads to reduced intrinsic factor.

B12 deficiency in most cases is due to the subject’s inability to absorb the vitamin rather than an insufficiency due to diet. It has also been shown through research that obese individuals who are currently taking medication to control gastroesophageal reflux may also report vitamin B12 deficiency.

What are the symptoms?

Some of the symptoms of vitamin B12 deficiency include:

• Anaemia and related tiredness, Breathlessness, palpitations
• Nerve problems like tingling and numbness
• Slower Reflexes
• Tongue ulcers
• Impaired vision

More severe symptoms of B12 deficiency include heart failure and permanent nerve damage.

Dietary requirements for B12 deficiency

For patients who have had weight loss surgery and are suffering from a vitamin B12 deficiency there are some dietary requirements that can help to increase B12 levels within the body. The best sources of B12 come from food items of animal origin, these foods include venison, liver, shrimp, and scallops. For those who are vegetarian kelp and fermented food items such as tempeh and miso, dairy and fortified breakfast cereals are suitable substitute to animal origin food products. B12 deficiency can be replaced by injections, sublingual, transdermal and nasal gel forms.

For any questions you may have in regard to weight loss surgery or vitamin B12 deficiency please contact Dr Siva Gounder at Perth Weight Loss and Surgery.