An average adult’s body contains around 3.5g of iron, with most of that contained within the blood in the form of haemoglobin. Iron is essential for humans to transport oxygen around the body effectively and you don’t need to be a biology whizz to know that oxygen is quite important to us humans.
Those with a rudimentary knowledge of nutrition may most associate iron with meat and it is this association which makes many people question whether vegans will naturally consume sufficient quantities of iron for their dietary needs. Iron is indeed abundant in a range of meats and other animal products. However, there are also many excellent vegan sources of iron and to assure optimum health, at least some of these iron-rich vegan foods should feature in a plant-based diet.
We’ll start by looking at some of the best natural sources of vegan iron before also considering if iron deficiency is a problem from which many vegans are likely to suffer. We’ll then conclude, for those revising for their “Iron Expert Master Level 12” badge, by looking at what iron actually is and also what it does in the body and why we need it. In case you were wondering, there isn’t really an Iron Master Level 12 badge (it’s actually a certificate).
How Much Iron Do We Need?
We defer to the National Health Service (NHS) when it comes to how much iron is needed and their advice at the time of writing is
- Men aged 19 and over – 8.7mg per day
- Women aged 19 to 50 – 14.84mg per day
- Women aged 51 and over – 8.7mg per day
The advice above is taken directly from the NHS, however, further information is widely available and we feel a little clarification is needed. The primary reason women need more iron than men is to compensate for the iron lost during menstruation.
During periods, most women will lose around 1mg of iron per day, with this figure higher for those who have heavy periods. Obviously, it isn’t only women between 19 and 50 who have periods, so in fact this higher level applies to both younger and older women who are menstruating.
Pregnant women also need higher levels of iron, the main reason for this being that their unborn baby will be establishing a reserve of iron which is drawn from the mother’s blood. Pregnant women may need as much as 27mg of iron per day.
In terms of children, iron requirements vary, peaking at around 11mg per day for babies between seven and 12 months. Adolescent boys will also need around 11mg, with girls of a similar age needing around 15mg. Precise needs vary at other times and range between 7mg and 10mg.
So, where can a vegan get these levels of iron, I hear you ask?
Vegan Food Sources of Iron
|Food||Mg of iron per 100g (edible portion)||% of intake per standard serving^|
|Green Lentils (boiled)||3.5||32%|
|Red Kidney Beans (boiled)||2.5||23%|
|Vegan Cornflakes (fortified)||7.9||27%/|
|Spinach (frozen, boiled)||1.7||16%|
|Cashew Nuts (roasted and salted)||6.2||20%~|
^ – based on 8.7mg per day and 80g of fruit/vegetables/grains/legumes/beans unless stated
~ – based on 28g serving
+ – based on 2 x 50g slices
/ – based on 30g
* – based on 10g
This information is drawn from various sources but primarily the Food Standard Agency’s Manual of Nutrition (11th edition) and Public Health England’s The Composition of Foods (7th summary edition)
As you can see from the table above that iron is found in a range of foods and so a vegan eating a healthy and varied diet is easily able to get sufficient iron for their body’s needs. The table also shows us the usual suspects cropping up, foods that frequently feature in our lists of good vegan sources of various nutrients, for example vegan protein or vegan sources of calcium. In summary, therefore, we can highlight the following as good options for vegan-friendly iron:
|Vegan Friendly Iron Sources|
|Beans & Legumes|
|Nuts & Seeds|
|Leafy Green Veg|
|Herbs & Spices|
Herbs & Spices are Great Vegan Iron Sources
Herbs and spices we say? Yes, indeedy. These flavour-packed goodies are rarely listed as great sources of nutrients, chiefly because we consume them in relatively small quantities. However, many herbs and spices have excellent claims to being “superfoods”. Almost all herbs and spices are packed with micro-nutrients and these are a great way to pack a little extra goodness into a meal, not to mention the brilliant taste and aroma they can bring to relatively bland vegan staples, such as quinoa, tofu and other grains.
Many spices are especially high in iron and such are the levels of this mineral that even a gram here or there will add up and help you easily consume enough iron on a vegan diet. For reference, one teaspoon of most ground spices is around 2.5g, although different herbs and spices have different volume to weight ratios so this can vary considerably.
That said, here are some of the iron values of popular and common herbs and spices. Note the first number is the amount of iron per 100g, with the second number being the amount of iron in 2g.
|Herbs & Spices||Iron per 100g|
|Dried Mixed Herbs||69/1.4|
As said, such foods are only consumed in very small quantities. But when you consider that both chillies and garlic (in fresh or powder form) also contain good levels of iron, it’s easy to see how a simple curry or other spiced dish (especially one with some greens and lentils in it!) can easily help a vegan reach their recommended iron intake.
Iron Fortification & Supplementation
Iron is one of a number of vital nutrients that is routinely added to certain foods, sometimes being required by law (in the case of non-wholemeal wheat flour). That means that breads, cereals and some other UK staples can be excellent sources of iron (as well as B vitamins, calcium and some other micro-nutrients).
Wholemeal bread is a good natural vegan iron source, as are other wholegrain foods, but if you like white bread that is also a good option. Vegan breakfast cereals are also a good choice and, in fact, around 40% of the iron in UK diets comes from cereals and related products.
Iron supplements are a slightly different issue and these would normally be taken in tablet form. Some vegans – and indeed non-vegans – may feel that it is necessary for them to take iron supplements and these are widely available without medical supervision.
This may be the case for those eating a restricted diet but in general we would say supplements are best reserved for those who are pregnant or who experience heavy bleeding during their periods. In such instances, iron may be prescribed by a doctor.
The Body’s Role in Producing Iron
As we have noted in other articles regarding vegan nutrition, the body is a highly complex machine with many interactions taking place. That means that two plus two doesn’t always equal four, which makes nutritional requirements difficult to understand and follow. The metabolic system is incredibly multi-faceted and relatively little understood and so equations are not quite as simple as “the body needs x, this food has x, therefore eating said food will deliver what the body needs”.
We noted in our feature on vegan sources of vitamin D that one of its key roles was to help the body absorb and use calcium. Some foods and nutrients work together, whilst others work against each other and this is just one aspect of what is called the bioavailability of a given nutrient. Some foods may have very high levels of a certain vitamin or mineral but if it is in a form the body can’t use (perhaps because the item also contains another nutrient which blocks absorption) then it is of little or no value.
This is not an area that is totally understood as yet and different peoples’ bodies function in slightly different ways too. However, there are some things that we do know about iron and being aware of them will mean you get the best bang for your vegan iron buck.
Dietary iron comes in two forms: non-haem and haem. About 90% of the iron we eat is the former, which is essentially iron salts. 10% (in the UK in general) comes from meat and this haem iron has good, largely non-variable absorption and bioavailability.
“Vegan iron”, or the non-haem iron found in pulses, grains, veg and so on (it is also found in dairy) is generally less well utilised by the body. Moreover, other factors can have a big impact on how much of this iron our bodies can use.
Let’s start with some good news. The body, incredibly clever organism that it is, absorbs iron better when it needs it most. So, those with low levels of iron, for example children, pregnant women and those who are menstruating, will absorb iron more efficiently than someone who has a full store of the mineral. Clever, eh?
Now for some bad news: iron is generally more bioavailable when consumed alongside meat. Fear not though, we have more good news: vitamin C is also a great way to increase the body’s efficiency in iron uptake. Many leafy greens boast both vitamin C and iron, so they are perfect, whilst adding a glass of orange juice to a meal (just drink it, don’t poor it in your lentil curry!) is another great option.
Other good choices include finishing with some high vitamin C fruit, such as strawberries or kiwi fruit, or adding peppers to a meal that is high in iron.
Lastly, it is worth noting that whilst vitamin C is good, tannin and some types of fibre are bad. Both can decrease absorption of iron and whilst trying to miss out fibre is probably counter-productive, trying to avoid tea and to a lesser extent coffee, around iron-rich meals is probably wise.
Tannins are a group of polyphenols and the ones found in teas (green, black, white and others) are particularly adept at limiting iron utilisation. If you having an iron-rich meal, not drinking tea immediately before, during or after is recommended, although consuming vitamin C as well can offset this somewhat.
One final area of confusion and complexity concerns spinach, which we discussed in our feature on calcium. Spinach (along with rhubarb and some other foods) is high in oxalates and these were (or still are, depending on your opinion) thought to interfere with the absorption of a range of nutrients. Oxalic acid is toxic in high amounts but it is more the way it inhibits nutrient absorption that causes the issue.
However, the latest research into the issue seems to suggest that the body can adapt to oxalic acid intake and essentially learn how to absorb iron (and calcium). Various studies, including one undertaken by the Institute of Food, Nutrition and Health in Zurich, have shown that contrary to previous opinion, oxalates in fruit and vegetables do not have a statistically significant negative impact on iron nutrition. Further research may be needed to confirm this 100% but none the less, spinach remains a hugely healthy and nutritious food.
Do Vegans Suffer from Iron Deficiency?
Some people assume vegans must be lacking in a whole range of nutrients but is there really a valid reason for concern about iron? As with many micro-nutrients the overall trends within the UK are towards a less healthy diet. The 2000-2001 National Diet and Nutrition Survey (NDNS) showed average iron intake for men aged 19-64 at a very healthy 13mg per day, well above the recommended levels.
This has dropped substantially and although most men are still meeting the Lower Reference Nutrient Intakes (LRNIs), an alarming number of women in the 11-18 age range are not, whilst a significant number in the 19-64 age range are also falling short. According to the British Nutrition Foundation (BNF), “the LRNI is the amount of a nutrient that is enough for only a small number of people in a group who have low requirements (2.5%)”. Again, according to the BNF, “Intakes below the LRNI are almost certainly not enough for most people.”
The NDNS Report of Years 7 and 8, which covers 2014-2016, showed that a huge 54% of girls (11-18) didn’t meet the LRNI, compared to 12% of boys. The numbers for 19-64 group show just 2% of men falling short of the LRNI but 27% of women. It must also be remembered that these are the lowest levels, thought to be sufficient for just 2.5% of the population, in contrast with the recommended levels which are believed to be adequate for 97.5% of people.
So, what we do know is that literally millions of people in the UK are consuming inadequate levels of iron. Whilst there is no concrete evidence to show that vegans are over-represented in this group, given that meat and animal products are a good source of iron (nutritionally speaking), it would seem reasonable to assume that lots of vegans are failing to consume enough of this micro-nutrient.
Vegans eating what some might deem a stereotypical vegan diet are probably getting lots of iron from the great foods mentioned and listed above. In fact, those eating such a healthy and varied diet are probably consuming more iron than many omnivores.
However, we certainly think that many vegans are falling short, especially those in the sorts of groups we have already mentioned who have higher than average iron requirements. As said, supplements are one option. However, heeding our advice regarding maximising absorption and throwing in a few extra serves per week of iron-rich vegan foods, such as legumes, greens, bread and spices is a more natural – and tasty – option.
Why Do We Need Iron?
Greens and beans at the ready, and eat! But why are we eating all this iron again? Well, iron, as alluded to earlier, helps the body utilise oxygen. Haemoglobin, which is essentially the red in our blood and largely made of iron, transports oxygen around the body, from the lungs to the various cells and tissues where it is needed. Iron is needed to make red blood cells and without it the process of transporting oxygen is diminished with a range of negative consequences.
Iron deficiency, as we have seen, is relatively common in the UK, and worldwide, it is the most common nutritional deficiency. Mild deficiency is not usually a major issue, although over time it can lead to insufficient levels of red blood cells and haemoglobin.
People associate anaemia with iron but in fact it can be caused by the lack of a number of nutrients. It is specifically iron deficiency anaemia that we are talking about here and that can cause a range of problems including fatigue, pale skin, irregular heartbeat and palpitations, a lack of energy, growth and developmental issues (in children) and shortness of breath.
What is Iron?
Well, to follow are usual description of what various nutrients are, iron is an element. You’ll find it on the periodic table in between manganese and cobalt. Iron, atomic number 26, symbol Fe (from the Latin ferrum), part of the transition metals group and the sixth most abundant element in the Milky Way (don’t ask how long it took us to weigh them all).
Iron is biologically crucial to many animals but has been manipulated by humans for around 6,000 years. Aside from its nutritional importance, it is commonly used in a range of ways, from tools to machines, as well as in ships, cars and buildings. Around 90% of the planet’s metal production is iron, much of which is used to make steel, with China by far the biggest producer.
Aside from all these fascinating iron facts though, there is a chance that you may be lacking when it comes to your iron intake. With so many great vegan ways to consume iron and lots of iron-rich vegan foods, that should be easy enough to remedy. Anyone for a bean and lentil curry and a glass of OJ?