Is There an Iron Supplement That Doesn't Cause Black Stools?

Why does iron supplementation cause such unpleasant side effects, including hard, black stools and a sore stomach?

This can be concerning for individuals who are taking iron supplements regularly. Not only is it distressing, it is also indicative of the microbiome disfunction that accompanies old-fashioned iron powders and capsules.

Fortunately, there is now a new iron supplement on the market that is designed to eradicate gastrointestinal side effects such as black stools - Nano Iron.

In this article, we will explore the benefits of Nano Iron and explain why it may be an excellent choice for individuals seeking an iron supplement that does not cause black stools.

We'll also go into detail about why you're getting black poo from traditional supplements.

Is there an iron supplement that doesn't cause black stools

Why Do Regular Iron Supplements Cause Black Stools?

Normal iron supplements can cause black stools due to the unabsorbed iron in the gut forming complexes with other compounds in the digestive tract.

Iron supplements usually contain elemental iron, which is the form of iron that the body can absorb. However, the body can only absorb a small amount of elemental iron at a time, and any excess iron remains in the digestive tract.

The excess iron in the gut can react with other compounds such as sulfur-containing amino acids or hydrogen sulfide produced by gut bacteria, forming non-absorbed iron complexes. These complexes can impart a black colour to the stool, making it appear dark or black. This is a common side effect of iron supplements and is not typically a cause for concern.

In addition to black stools, other gastrointestinal side effects can also occur with traditional iron supplements. These can include constipation, diarrhea, stomach cramps, and nausea. These side effects can be significant enough to cause some individuals to stop taking their iron supplements, which can lead to further health problems related to iron deficiency.

Common Iron Supplements That Can Cause Black Poo

Ferrous sulfate is one of the most widely used iron supplements and also one of the most common causes of black stool. It provides iron in the ferrous state (Fe2+), which is a form that is readily absorbed.

Ferrous gluconate is another commonly used iron supplement that can cause darkened stools. It combines ferrous iron with gluconic acid for increased bioavailability.

Other types of iron supplements that may cause black stool include:

  • Ferrous fumarate - Provides ferrous iron bound to fumaric acid.
  • Ferrous asparto glycinate - Chelated ferrous iron.
  • Carbonyl iron - Pure elemental iron in the form of microbeads.
  • Iron polysaccharide complex - Iron bound with a polysaccharide.
  • Heme iron polypeptides - Iron derived from hemoglobin.
  • Ferrous bisglycinate - Ferrous iron chelated with glycine.

The level of elemental or absorbable iron varies amongst these different supplements. Generally the more elemental iron a supplement contains, the more likely it may cause black stool as a temporary side effect. The degree of darkening can also depend on the individual and dosage consumed.

How to Identify Black Stools from Iron Supplementation

Black stools, also known as melena, can occur when the iron in the supplement combines with digestive enzymes and causes stool to turn black. The following information may help you identify black stools from iron supplements:

  • Black stools are typically shiny and black in color, almost like tar or dark chocolate. They may be sticky and have a foul odor.
  • The color change is due to the presence of iron and is usually accompanied by a change in consistency and odor of the stool.
  • Black stools caused by iron supplements can occur within a few days of starting the supplement, and may persist for as long as the supplement is taken.
  • If you notice any other symptoms, such as abdominal pain, nausea, vomiting, diarrhea, or constipation, you should contact your healthcare provider as these may be signs of a more serious issue.

Nano Iron: A supplement that does not cause black or tarry stools

Nano Iron is a type of iron supplement that has gained popularity in recent years for its ability to provide the body with iron without causing some of the uncomfortable side effects associated with traditional iron supplements. One significant advantage of Nano Iron is that it is gentle on the gut, which means it does not cause constipation or other gastrointestinal issues.

In addition, Nano Iron is designed to have minimal impact on the gut microbiome. This is a critical benefit since the gut microbiome plays a crucial role in overall health and well-being. Traditional iron supplements, on the other hand, can disrupt the delicate balance of bacteria in the gut, leading to further digestive problems.

Another essential benefit of Nano Iron is its high bioavailability. Nano Iron is more easily absorbed by the body than other forms of iron supplements, such as ferrous sulfate. This means that individuals taking Nano Iron may need to take smaller doses to achieve the same results as they would with other forms of iron supplements.

Overall, the benefits of Nano Iron make it an excellent option for individuals who struggle with the side effects of traditional iron supplements. Its gentle impact on the gut, no constipation, and high bioavailability, combined with its ability to provide the body with essential iron, make Nano Iron an effective solution for individuals looking for an iron supplement that does not cause black stools.

Why Nano Iron Does Not Cause Black Stools

Nano Iron is a type of iron supplement that is designed to be gentle on the gastrointestinal system. Unlike traditional iron supplements, which can cause side effects such as black stools, Nano Iron is formulated to minimize these types of gastrointestinal symptoms.

One reason why traditional iron supplements can cause black stools is that they contain high levels of elemental iron. This type of iron can be difficult for the body to absorb, leading to the formation of non-absorbed iron complexes in the digestive tract. These complexes can react with certain compounds in the gut, leading to the characteristic dark color of black stools.

In contrast, Nano Iron is made up of extremely small particles that are easily absorbed by the body. This means that there is less unabsorbed iron remaining in the gut to form complexes and cause black stools.

In addition, Nano Iron is designed to be gentle on the gastrointestinal system, which means that it is less likely to cause irritation or inflammation in the digestive tract. This can help to reduce the risk of other gastrointestinal side effects, such as constipation or diarrhea, which can also be a concern when taking traditional iron supplements.

Overall, the unique formulation of Nano Iron makes it an excellent choice for individuals who need to supplement their iron intake but are concerned about the side effects associated with traditional iron supplements, such as black stools. By minimizing gastrointestinal side effects and being gentle on the gut, Nano Iron provides an effective and convenient solution for maintaining healthy iron levels without causing discomfort or disruption to the digestive system.

Should You Stop Iron Supplements if Poo is Black?

Seeing black, tarry stool while taking iron supplements can be alarming, but in most cases it is not a cause for concern or a reason to stop taking the iron. The black color is a harmless side effect caused by the iron sulfide produced as the supplement passes through the digestive tract.

Unless there are other troubling symptoms present, like bloody stool, continuing diarrhea, severe pain, or vomiting, the black stool itself is not dangerous. However, you should notify your doctor to discuss the timing and dosage of the iron if the black stool persists or worsens.

Your doctor may recommend adjusting the iron supplement type or dosage to reduce staining while still treating iron deficiency. Typically there is no need to stop the iron supplements unless advised by your doctor, as maintaining adequate iron levels is important. Be sure to also report any constipation or diarrhea that results from iron supplements, as the dosage may need modifying to improve digestion.

Does black poop mean iron tablets are working?

While black poop can signify that iron from the supplement is getting through the gastrointestinal system, it does not necessarily mean the body is absorbing a sufficient amount of the iron. Stools can become black even if very little iron is being utilized by the body.

The colour change happens when there is excess iron in the digestive tract. The only way to know if your iron tablets are effectively raising iron levels is through follow-up blood work and monitoring symptoms of deficiency. Work with your healthcare provider to ensure your iron supplement routine is optimal for your needs.


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Why does your stool turn black when taking iron?

Traditional iron supplements can cause stool to turn black due to the reaction between iron and digestive enzymes. This reaction can change the color and consistency of stool, causing it to appear black and tar-like. This is a common side effect of iron supplements, and is generally not a cause for concern, although it can be avoided entirely by taking Nano Iron.

Should I stop taking iron supplements if my stool is black?

If your stool turns black after taking iron supplements, it is generally not necessary to stop taking the supplement. This is a common side effect and does not necessarily indicate a problem. However, if you are concerned or experience other symptoms such as abdominal pain, nausea, vomiting, diarrhea, or constipation, you should talk to your healthcare provider. You should also consider supplements such as nano iron which do not negatively impact your microbiome.

How long does poop stay black after iron tablets? 

Black stool caused by iron supplements can persist as long as the supplement is taken. However, if you stop taking the supplement, your stool should return to its normal color within a few days. If your stool remains black after stopping the supplement, or if you experience other concerning symptoms, you should talk to your healthcare provider.