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Iron Deficiency After Gastric Bypass Surgery

What is iron deficiency after gastric bypass surgery?

Iron deficiency and anemia are more common after a gastric bypass than after a sleeve gastrectomy or an adjustable gastric band. This is especially true in women.

What causes iron deficiency after gastric bypass surgery?

Iron deficiency is a side effect that results from the changes made during the surgery. Most of the iron from foods is absorbed in the first part of your small intestine (duodenum). But after a gastric bypass procedure, food bypasses the duodenum. This can lead to iron deficiency and other nutrition problems.

The amount of iron in a standard multivitamin (18 mg) may not be enough to prevent anemia if you have this kind of surgery. You'll need to take more iron if your iron level is low after a gastric bypass.

Who is at risk for iron deficiency after gastric bypass surgery?

Iron deficiency is more common in women who have this surgery, particularly in women who are still menstruating. It's also found in women after menopause. But anemia in this subgroup of women might not be related to the gastric bypass surgery. Men who have had gastric bypass may also get iron deficiency. But it happens less often in men.

What are the symptoms of iron deficiency after gastric bypass surgery?

Iron is important for the health of your hair, skin, and nails. It also helps make hemoglobin. This is the substance inside red blood cells that carries oxygen throughout your body. When you're anemic because of iron deficiency, you may have:

  • Lack of energy or tiredness (fatigue)

  • Weakness

  • Headache

  • Rapid heartbeat

  • Hair loss

  • Brittle nails

  • Pale or yellow skin

  • Shortness of breath

  • Chest pain

  • Strange pounding sensation in your ears

  • Craving for substances with no nutritional value, such as ice or clay

How is iron deficiency after gastric bypass surgery diagnosed?

Your healthcare provider will note any of the above symptoms you tell them. They will also order blood tests to find out if you have an iron deficiency or anemia. In its early stages, iron deficiency starts to use up the stores of iron in your body. This can be seen by testing your levels of ferritin. This is a protein that stores iron in your body. If your ferritin levels are low, your iron is likely low.

If your iron deficiency has turned into iron deficiency anemia, you'll need a complete blood count test to find any other problems. These might include low hemoglobin, lower numbers of red blood cells, and smaller red blood cell size.

For men, or for women past menopause, iron deficiency anemia might not be related to gastric bypass surgery. Your healthcare provider will need to be sure that you aren't anemic from blood loss elsewhere, such as from your intestine. You may need a colonoscopy to look for a source of blood loss in your large intestine.

How is iron deficiency after gastric bypass surgery treated?

Many people can raise their iron levels by making some changes to their diet. If your iron deficiency is related to a gastric bypass procedure, your healthcare team will probably prescribe iron supplements. This extra iron should come from a prescription from your provider, not from an over-the-counter (OTC) supplement you pick yourself. The exception to this is if your provider recommends a certain OTC iron product for you. Your healthcare provider may recommend a certain type of iron that you could absorb better after a gastric bypass.

If you're a teen boy or girl, or a woman of childbearing age, you may need 2 multivitamins plus 50 mg to 100 mg of iron each day. You may also need a vitamin C supplement or other supplements to help your body absorb more iron. Your healthcare provider will tell you the right amount of iron and possibly other supplements that you may need.

Iron supplements can cause side effects. Many people have constipation (or diarrhea), nausea, abdominal cramping, bloating, and gas.

For some people, supplements aren’t enough. This is usually true for women with heavy menstrual periods. You may need iron through an IV (intravenous) line or blood transfusion. Or you may need more surgery on your bypass to increase the amount of iron you absorb.

What can I do to prevent iron deficiency after gastric bypass surgery?

You should have blood tests before weight-loss surgery to find out if you have any vitamin or mineral deficiencies. These might include low levels of iron, vitamin B-12, or folate. Getting treatment for these deficiencies before your surgery will help your quality of life after surgery.

After gastric bypass surgery, you'll need to monitor your level of iron and other nutrients for the rest of your life. You can get iron deficiency and anemia years or decades after your gastric bypass surgery. Your healthcare provider should measure your iron levels 6 months after weight-loss surgery and at least once a year after that. You should also have a complete blood count test.

Red meat, poultry, seafood, leafy greens, legumes, iron-fortified grains, and other iron-fortified foods are all good sources of iron. Drinking more than 2 to 3 cups of milk a day may decrease how much iron you absorb. But dietary changes alone may not be enough to prevent or fix an iron deficiency related to a gastric bypass procedure. Work with your healthcare provider to find the right iron supplement plan for you. To ensure your long-term health, make sure to keep all of your medical appointments.

Key points about iron deficiency after gastric bypass surgery

  • Iron deficiency and anemia are common after a gastric bypass or other weight-loss surgery, especially in women.

  • For men, or for women past menopause, iron-deficiency anemia might not be related to the gastric bypass surgery.

  • Your healthcare provider will probably prescribe iron supplements.

  • You can get iron deficiency and anemia years or decades after your gastric bypass surgery.

  • You'll need to monitor your level of iron and other nutrients for the rest of your life.

  • Regular follow-up visits with your healthcare provider are important for maintaining your overall health.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

  • Know the reason for your visit and what you want to happen.

  • Before your visit, write down questions you want answered.

  • Bring someone with you to help you ask questions and remember what your healthcare provider tells you.

  • At the visit, write down the name of a new diagnosis and any new medicines, treatments, or tests. Also write down any new instructions your healthcare provider gives you.

  • Know why a new medicine or treatment is prescribed and how it will help you. Also know what the side effects are and how to manage them.

  • Ask if your condition can be treated in other ways.

  • Know why a test or procedure is recommended and what the results could mean.

  • Know what to expect if you don't take the medicine or have the test or procedure.

  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.

  • Know how you can contact your healthcare provider if you have questions.

Online Medical Reviewer: Marianne Fraser MSN RN
Online Medical Reviewer: Rajadurai Samnishanth
Online Medical Reviewer: Susan K. Dempsey-Walls RN
Date Last Reviewed: 2/1/2024
© 2000-2024 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.