The first and most important thing you need to realise about iron and iron supplementation is that iron needs differ from person to person.

You might think that’s obvious, but if you were to Google “How long does it take for iron supplements to work?” you’ll mostly find specific answers like 2 weeks or 2 months.

All of these may be true – because many factors come into play when determining when you should take iron, how iron is absorbed in your body, and how much iron you need.

That’s why today, we’ll examine each of them so you can make clearer, more informed decisions and achieve the results you’re looking for.

To start, let’s make a differentiation between how long it takes for iron to actually “work” and how long it takes for your body to “absorb” iron.

Active Iron consistently tops the charts as one of the best iron supplements on the market. Active Iron’s award winning iron supplements work quickly, and its Kind & Strong formulation is kind on the stomach and strong on absorption.



How long does it take for iron pills to work?

Most people feel better taking an iron supplement after three weeks but it may take up to 12 weeks to feel an increase in energy.

You may need to continue supplementing your dietary intake of iron to meet your body’s daily iron needs.


How long does iron take to get into your system after taking iron ?

How long it takes for iron to get into your system depends largely on (1) why your levels were low in the first place and (2) how far below normal they were. The lower your current level, the longer it will take to build up a sufficient amount of iron in your system.

Consider the following cases:

  • If you need more iron because of menstruation, it will usually take a bit longer to build up because you’ll continue to experience blood loss with every period.
  • If your dietary intake of iron is insufficient, it may replenish very quickly if your supplement allows you to absorb it better.
  • If you change your current dietary habits to focus more on rich sources of iron, it might still take a while to get your iron levels back to normal.



The most important factors to consider when taking an iron supplement


Your current diet and nutritional habits

An iron-rich diet can be challenging to sustain, especially if you need to build up a significant amount of iron.

In this section, we are going to look at foods that decrease iron absorption, as well as foods that increase iron absorption.


Foods that decrease iron absorption

Some foods and nutrients are natural iron inhibitors – they diminish the absorption of iron and make it difficult for you to reach optimal levels.

These include:

  • Phytic acid (often found in grains and legumes)
  • Tannins
  • Polyphenols (found in tea)
  • Milk
  • Caffeine
  • Some of the proteins found in soybeans

(And, considering many people’s days start with a cup of coffee or a bowl of milk and cereal, we can quickly begin to see why iron absorption is a challenge.)


Foods that increase iron absorption

On the flip side, other foods are known for increasing your iron absorption, and they are often recommended to be taken alongside iron supplements. These include:

  • Citrus items and citric acid – lemons, lemonade, oranges, orange juice
  • Vitamin C
  • Vitamin A and beta-carotene
  • Beef
  • Meats, fish, and poultry


How soon after taking iron supplements will I feel better?

It can take anywhere from three to 12 weeks to feel better after taking iron supplements.For example, Active Iron is clinically proven to increase iron and energy levels in six weeks, but many report seeing an increase in their energy levels after three weeks.

In all cases if you suspect you need more iron, the best approach is to talk to a professional who can guide you and help you figure out the reasons you might not be feeling well and if iron is a factor in you feeling tired or fatigued. From there, they can guide you on whether iron supplements will help you feel better or not.



If you want to reap all the benefits of optimal iron intake, you need to ensure you are absorbing iron well, and getting enough iron in your diet.

If your diet isn’t giving you enough iron, and you choose to supplement your iron intake, you will want to choose a supplement that provides optimum absorption and is kind to your stomach.

Active Iron supplements are designed with a unique formula that targets the right place for absorption, the DMT-1. This helps reduce oxidation, thus protecting the gut from inflammation. As a result, Active Iron is highly absorbed compared to other iron supplements¹, making it gentle on the stomach and clinical results have shown that it increases iron levels by 94%².


So if you want to know how long it will take for your iron supplements to work, remember this guide and start taking Active Iron today.


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Some FAQs from customers:


How quickly do iron supplements work?

Haemoglobin blood levels generally increase after 2 to 4 weeks of supplementation. Symptoms like fatigue, weakness, and headache should start to improve during this time. It typically requires around three months for iron stores (measured by ferritin levels) to reach a normal level.


How long should you take iron supplements for?

Iron supplements should be taken for at least 6 months, and up to 12 months. The best way to ensure adequate absorption is to take them on an empty stomach or allow 2 to 3 hours between meals as certain food, drink and medicines may inhibit iron absorption.

How long does it take for iron levels to drop?

Your body uses about 500mg of iron to make about 2g/dl of haemoglobin, which is a protein in your red blood cells that carries oxygen. We require extra iron to create energy and for our body to function correctly.

When we stop taking iron, the body uses internal reserves of iron. The drop in iron levels will depend on our diet and way of life. For example, if you like doing endurance sports your iron levels could fall quicker.

As iron levels fall below the standard range, you may notice fatigue, headaches, and eat less.


¹Wang et al. 2017, Acta Haematologica, ²Ledwidge et al. 2021. Data on file.