The Importance of B-Vitamins After Weight Loss Surgery

B-vitamin deficiencies after weight loss surgery

B-vitamins include B6 (pyridoxine), folate (folic acid), vitamin B12 (cobalamin), B1 (thiamin), riboflavin, niacin, pantothenic acid, and biotin. These vitamins are needed by the body to support metabolism and help produce energy. B-vitamins are water-soluble, meaning that they dissolve in water and the body does not store these vitamins for later use and is excreted. Some B-vitamin deficiencies are more common than others after bariatric surgery.


Vitamin B12

Vitamin B12 is important for growth, a proper functioning nervous system, and red blood cell production. Vitamin B12 deficiency can be common after gastric bypass surgery. The surgical alteration of the digestive tract interferes with the absorption of vitamin B12. This vitamin is broken down by stomach acid in order for the vitamin to be carried through the beginning of the small intestine (duodenum) where it is then bound to something called intrinsic factor that helps with absorption which occurs at the end of the small intestine (ileum). With changes made to the stomach and bypassing most of the duodenum, cells of the stomach are unable to produce adequate amounts of intrinsic factor to help with absorption of vitamin B12. Vitamin B12 can be found in different forms of supplementation, but for some bariatric patients, sublingual B12 is a common option. This form of supplementation dissolves under the tongue to ensure absorption. Vitamin B12 is commonly found in animal products like milk, yogurt, cheese, meat, fish, poultry and eggs.

 Bariatric Fusion B12

Symptoms of B12 deficiency include anemia, constipation, fatigue, headaches, mouth lesions, and irritability.


B1 (thiamin)

Vitamin B1 is essential in helping the body convert the food you eat into energy. This vitamin is absorbed in the small intestine (duodenum and jejunum). After gastric bypass and sleeve gastrectomy surgery, some patients may experience nausea leading to consistent vomiting that can result in thiamin deficiency. Deficiency of vitamin B1 can also occur from caloric restriction due to a reduced stomach size and not adhering to a regular vitamin regimen causing malnutrition. Thiamin is found in pork, peas, whole-grain and enriched-grain products.

 Bariatric Fusion B1

Symptoms of B1 deficiency include confusion, digestive problems, loss of appetite, memory loss, weakness, and nervousness.


Folate (AKA Folic Acid)

Folate is needed by the body for metabolic functions and red blood cell production. It is also a very important vitamin during pregnancy to prevent neural tube defects. Folate is absorbed throughout the entire small intestine (duodenum, jejunum, and ileum), so a deficiency is usually due to a lack of folate consumed in the diet. Folate is found in fortified cereals, legumes, leafy vegetables, and other fruits and vegetables.

Symptoms of Folate deficiency include anemia, shortness of breath, headaches, fatigue, insomnia, and paranoia.



Riboflavin is utilized by the body to produce energy, assist with cellular function, and growth. Inadequate intake of riboflavin from food can result in deficiency which can be common due to restriction of the stomach after weight loss surgery. Riboflavin is commonly found in milk, enriched grains, lean meats, and eggs.

Symptoms of Riboflavin deficiency include blurred vision, depression, hair loss, dermatitis, loss of sensation, sleepiness, mouth lesions.



Niacin is important in carbohydrate, protein, and fat metabolism in the body. This vitamin is absorbed in the small intestine (duodenum and jejunum) resulting in a higher risk of deficiency in weight loss surgery patients. Niacin is found in peanut butter, beef, poultry, fish, and fortified grain products.

Symptoms of Niacin deficiency include canker sores, confusion, irritability, loss of appetite, nausea, inflammation.



For someone that is consuming a wide variety of foods, a biotin deficiency is very uncommon. Following bariatric surgery, restriction and malabsorption can hinder your ability to consume a wide variety of food options which could then result in biotin deficiency. Biotin can be absorbed in the small intestine (duodenum and jejunum) and large intestine. Foods like eggs, peanuts, fish, sweet potatoes and almonds contain biotin. 

Symptoms of Biotin deficiency include hair loss, insomnia, inflammation of the eye, and dermatitis.


Pantothenic acid

Pantothenic acid assists in fatty acid synthesis. A wide variety of plant and animal foods contain this vitamin. This vitamin is absorbed mostly in the small intestine (jejunum). Pantothenic acid deficiencies can be seen in cases of malnutrition. It can be found in foods like yogurt, sweet potatoes, milk, avocados, eggs and beans.

Symptoms of pantothenic acid deficiency include abdominal pains, depression, eczema, hair loss, immune impairment, nausea, and insomnia.


Vitamin B6 (Pyridoxine)

Vitamin B6 is involved in many enzyme reactions and protein metabolism in the body. This vitamin is absorbed in the small intestine (jejunum). A deficiency in vitamin B6 can result from malabsorption in the body and is often associated with other B-vitamin deficiencies like vitamin B12 and folate. Vitamin B6 can be found in many foods such as beans, chicken, bananas, baked potatoes, pork, fish, nuts and fortified breakfast cereals.

Symptoms of B6 deficiency include acne, microcytic anemia, arthritis, dizziness, fatigue, impaired wound healing, irritability, and hair loss.


B-vitamins offered at Bariatric Fusion

Bariatric Fusion offers corrective B-vitamin options for those who need an extra supplement to correct any deficiencies. These supplements include B1 (Thiamine), Biotin, Sublingual B12 (for optimal absorption), and a B-50 complex that contains all eight B-vitamins.


Check out our easy to use B Vitamins Here