What Happens to Your Digestion When You Take Iron Supplements

Iron supplements can help if you have low iron levels, iron deficiency anemia, or have difficulty meeting your daily iron needs through diet alone. Common side effects of using iron supplements, especially at doses of 45 milligrams per day or more, include: digestive symptoms like constipation and bloating.

Current evidence suggests that iron supplements cause constipation through two proposed mechanisms: bacterial imbalances And loss of water in the intestine.

1. Bacterial imbalances

Iron supplements, especially unabsorbed iron, can change the balance of bacteria in your gut. They encourage potentially harmful bacteria like E.coli And Salmonella to grow, while reducing those that are useful like lactobacilli.

This change may increase the organisms that make methane gas. Too much methane can slow digestionwhich can cause constipation and bloating. However, not all studies agree that methane is a direct cause of constipation. Further research is needed to understand the relationship.

2. Loss of water in the intestine

When excess iron remains unabsorbed in your stomach, it removes water from the lower parts of your digestive system, like your colon. THE the colon needs water to keep stools soft. Losing this water can make your stools hard and lead to constipation.

If you are constipated or have fewer bowel movements after taking iron supplements, consider these ways to relieve or manage constipation:

• Take iron on an empty stomach: Your body absorbs iron better when you take it on an empty stomach. Better absorption may mean less constipation. Try to take iron at least 30 minutes before eating.
• Drink plenty of water: Drinking more water or other fluids can help keep your stools soft, as iron tends to move water away from the colon. Aim for at least two to three liters of water per day.
• Eat more fiber: Foods high in fiber like pears, vegetables, beans, and whole grains can help keep your stools soft. You can also try a fiber supplement such as psyllium husk.
• Try bowel training: Practice trying to have a bowel movement at the same time every day to help you establish a routine. Research suggests that having a bowel movement 15 to 45 minutes after breakfast can help because eating stimulates the bowel.
• Exercise: Exercise at least 30 minutes a day. Research suggests that simple daily exercise, such as walking, can help manage constipation.
• Consider using a stool softener: If lifestyle approaches don’t help, consider stool softeners like Colace (docusate sodium) or mild laxatives like Senakot (senna) to help make bowel movements easier.
• Reduce the dose: Talk to your doctor about reducing the amount or frequency with which you take iron to minimize your risk of side effects.

Other potential side effects of oral iron supplementation include:

• Nausea
• Vomiting
• Diarrhea
• Gas
• Metallic taste in the mouth
• Tooth coloring
• Black or green Tarry stool
• Abdominal pain

You may have other options for increasing your iron intake.

Different Types of Oral Supplements

Using another form of iron may improve your bowel movements. Common forms of oral supplementation include:

• Ferrous fumarate
• Ferrous gluconate
• Ferrous sulfate

Studies suggest that the form of iron called ferrous sulfate is more likely than other forms to cause constipation.

Iron IV

Iron given intravenously (IV) usually does not cause constipation because it passes directly into your bloodstream instead of through your intestines. A healthcare professional must administer it, so it is less convenient for many people. IV iron is also much more expensive – more than 60 times the price of iron pills.

Slow-release or sustained-release iron supplement

Extended-release iron tablets release iron slowly, which may reduce the amount of unabsorbed iron in the gut and reduce the risk of constipation, although research is inconclusive. These forms may not be equally absorbed, making them less effective for people with severe anemia.

Dietary iron

Your body absorbs iron from food in smaller amounts, reducing the risk of constipation and other digestive symptoms. For example, if you consume 10 to 15 milligrams of iron each day, you only absorb about 1 to 2 milligrams.

Iron-rich foods include:

• Lean meat
• Seafood like oysters and clams
• Nut
• Beans
• Vegetables
• Enriched grain products

See a doctor immediately if you have constipation and any of the following symptoms:

• Blood in your stool
• Rectal bleeding
• Constant abdominal pain or cramps
• Lower back pain
• Fever
• Inability to pass gas