The best iron supplements to take for sensitive stomachs.

If you suffer from a sensitive stomach, finding an iron supplement that does not upset your stomach is often a challenge. It is important to find the right iron supplements and formats that work for sensitive stomachs; for example, maybe lower dose iron supplements that give appropriate iron absorption.

Here we will break down the types of iron supplements and what you need to know when finding the best supplement for your sensitive stomach. We will cover the following:

  • The different types of iron supplements you can take
  • The benefits of oral iron supplements
  • What are liquid iron supplements?
  • Why do some iron supplements upset your stomach?
  • Which iron supplements are gentle on your stomach
  • How Active Iron supplements don’t upset your stomach
  • How to make sure iron supplements don’t upset your stomach

Types of iron supplements

There are several different ways to increase your iron intake through supplementation. Traditionally there are:

  • Oral iron
  • Low dose – available over the counter
  • High dose iron – prescription only
  • Intravenous infusion – undertaken in the hospital whilst being monitored.

The type of iron you are recommended to take will depend on any symptoms you experience, taking into account your diet and blood test results. There is not necessarily the same fix for everyone. Low iron is fairly common, with 1 in 4 women having low iron.¹

Oral iron supplements

If your blood test results reveal you have low iron, often a very high dose of iron will be prescribed orally to balance out your levels quickly. However, this can be harsh on your stomach and isn’t always well absorbed, causing some unpleasant side effects.

This often results in 50% of people stopping their prescribed high-dose iron supplements². These side effects commonly include:

  • Nausea
  • Stomach Cramps
  • Constipation
  • Diarrhea
  • Black Stools

If the dose is lower you are less likely to experience symptoms, yet very low doses may not replenish levels adequately or quickly enough. Finding an iron supplement that works well with sensitive stomachs and releases iron into your body without side effects is important. Active Iron is an iron supplement that increases iron and ferritin stores by up to 94%.³ Active Iron is both kind on the stomach and strong on absorption, offering fantastic benefits while helping to prevent gut irritation.

Liquid iron supplements

One option for iron supplements is liquid iron supplements, where the liquid is targeted to release iron quickly into your body. Often these doses are very small, ranging from 2mg – 5mg—however, the recommended daily intake is 14mg.

Some side effects of taking liquid iron supplements include teeth staining, a horrible metallic taste that’s difficult to overcome, a burning sensation in the esophagus, diarrhea, and nausea. Active Iron is designed to target the body’s site of iron absorption, where it is best absorbed, while still reducing the likelihood of side effects. That’s why it is the best alternative for sensitive stomachs.

Why do some iron supplements upset your stomach?

Many iron supplements upset your stomach because they oxidize in the gut and as a result, are poorly absorbed (typically, just 10% is absorbed). This oxidation and poor absorption cause gastrointestinal side effects such as nausea and constipation in 8/10 people.⁴ The higher dose of iron in supplements, the more likely symptoms are to present. It is important to find a high-quality supplement that does not cause these side effects and discomfort. Active Iron offers a great solution to help avoid gut irritation from iron. Unlike other oral iron, its whey protein formula protects the iron from oxidation, allowing for 2X better absorption⁵ of iron sulphate.

How to take iron supplements and not upset your stomach

Often, traditional iron supplements come with advice on how to take them in the best way not to upset your stomach. Advice to take with food or a heavy drink, such as orange juice or milkshakes, can help to alleviate some of the symptoms that are commonly associated with oral iron supplements. Food will help digest the iron supplement at the same time, so the stomach is not digesting the supplement while empty, making it gentler to absorb. Usually, if you do take supplements on an empty stomach, it can really upset your stomach. Active Iron was created to avoid this need and make it easier to take iron supplements at any time of day.

Iron supplements that are gentle on your stomach

Traditionally, iron supplements were very harsh on the stomach and caused many stomach complaints, resulting in lapsed usage.

Sometimes the symptoms of supplementation are worse than those of low iron, so many people choose to avoid the symptoms that come with taking high-dose iron and opt to live with low iron levels instead. This can cause chronic fatigue, weakness, and breathlessness, to name a few. To mitigate this, liquid iron supplements were introduced as a better alternative for those with sensitive stomachs and difficulty completing prescription recommendations.

However, liquid iron has its own issues and is not as well absorbed. It can have additional side effects on top of those commonly found with traditional iron supplements, along with the possibility of staining your teeth, which one would obviously want to avoid!

Active Iron was created to solve the issues of oral iron supplements and give users the boost of iron they need while helping to avoid uncomfortable side effects. Active Iron is less likely to cause upset stomachs than more traditional iron supplements and delivers the strong doses of iron needed in a supplement.

Active Iron – An iron supplement that doesn’t upset your stomach

Active Iron’s iron capsules are designed to help prevent side effects, e.g. feeling sick, nauseated, and constipated. Active Iron’s ground-breaking protein formula targets the body’s natural site of iron absorption, the DMT-1. This helps to increase the amount of iron absorbed. As a result, Active Iron is less likely to cause gut irritation than other iron supplements and has been clinically proven to increase iron stores by 94%.³ These results remain indifferent regardless of dosage, unlike many iron supplements where the higher the dose, themore symptoms reported. Participants also reported higher energy levels and a reduction in tiredness and fatigue.

Where to buy iron supplements for sensitive stomachs?

As mentioned, the best option for sensitive stomachs is Active Iron and it is important to maintain a healthy iron level, especially in women where low iron levels are common.

In the USA

In the USA,  Active Iron is available on Amazon.

How to make sure iron supplements don’t upset your stomach

The answer is simple, buy Active iron.  Active Iron is the only iron supplement that is clinically proven to be 2X better absorbed,⁵ increase iron stores by 94% and help avoid gut irritation.³ In fact, Active Iron is so gentle that you can take it on an empty stomach.

Gone are the days when you need to worry about an upset stomach when taking iron supplements!


¹NICE. Anaemia – iron deficiency. September 2018

²Tolkien et al. PLoS ONE 2015; 10(2): e0117383. doi:10.1371/journal.pone.01173832015.

³Ledwidge et al. 2021, Data on file. doi:

⁴Pereira D et al BMC Gastroenterol 2014 Jun 4;14:103. doi: 10.1186/1471-230X-14-103

⁵Wang et al. 2017, Acta Haematologica, 138: 223-232.

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