Vitamin Supplementation After Weight Loss Surgery

Most patients who undergo weight loss surgery are aware of the life-long vitamin regimen following surgery. The fact is, bariatric surgery changes how your body digests and absorbs food and nutrients. Since you’ll be eating less food after surgery and you’ll be consuming fewer nutrients. Symptoms of vitamin deficiencies can be subtle, but some deficiencies can be serious. So what happens when a bariatric patient fails to take the appropriate vitamins after surgery?


Most people have heard of anemia which usually stems from iron deficiency. This condition, where there’s not adequate iron to create red blood cells, is marked by lethargy and weakness. It may also result in changes in the hair, skin and nails. A deficiency in iron may also cause shortness of breath and even heart palpitations. Iron’s primary job is to store and transport oxygen to where it’s needed in the body. Iron is vital to the body’s metabolism as well as necessary functions like healing, detoxification and growth.

With the decreased amount of stomach acid following weight loss surgery, it is more difficult for your body to convert dietary iron from foods like meat, beans, greens, or nuts, into more usable forms in the body. On top of that, if you had a gastric bypass procedure the portion of the small intestine that is responsible for absorption of iron is eliminated from the digestive process.

B Vitamins

The deficiency of Vitamin B12 can result in a different form of anemia known as pernicious anemia. Bariatric patients can also develop folate deficiency, with levels of folic Acid (Vitamin B9) being too low, and deficiency in Thiamine (Vitamin B1). Initial symptoms of waning B12 may be tiredness, weakness, paleness and lightheadedness. As the deficiency progresses further, more serious ailments including nerve problems, numbness or tingling, depression, memory loss, and vision loss can occur. B12 plays a role in the growth and replication of cells as well as the function of the nervous system.

The stomach is altered in stapled bariatric procedures, including the sleeve and bypass. The stomach produces a substance called Intrinsic Factor which aids in the absorption of B12. Both stomach acid and Intrinsic Factor are reduced when the size of the stomach is reduced. This makes absorption of B12 more difficult. B12 deficiency can develop slowly, and may take years to present, so long term supplementation and monitoring of B vitamins is important beyond the first year.

Calcium & Vitamin D

Calcium deficiency results in the leaching of calcium from stores in the body, weakening bones and teeth. This leads to conditions like osteoporosis and increased risk of fractures. This issue can be compounded by the decrease in bone density caused by the change in daily weight bearing with weight loss. Calcium also regulates heart rate and nerve transmission.

In addition, the body needs Vitamin D to absorb the Calcium. Vitamin D helps in the prevention of cancers, including breast, prostate and colon, as well as dementia. Without Vitamin D, patients can experience chronic pain and weakness as well as frequent infection and depression. We routinely check Vitamin D levels since it is the most common deficiency in bariatric patients.

How Do You Avoid Deficiencies Post-Op?

With the changes both in anatomy and diet that come with bariatric surgery, it is vital to take vitamins post-op. We strive to help you understand the importance of these vitamins. Vitamin deficiencies are much easier to prevent than they are to treat. Oftentimes, bariatric formulated vitamins are recommended. These specially tailored vitamins can come with a higher price tag than the typical vitamins you might pick up at the drug store, but it is important to understand they are different.

We understand that taking vitamins long-term can be a challenge. But, they are essential to keep you healthy and strong. Further, as bariatric surgery research is broadened, new information and recommendations may develop. Even if your weight loss is excellent and you feel good, it’s important to follow up…we will check your body fat and check your vitamin levels.

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