But what about vegan diets? Don’t all those phytates, polyphenolics, and other plant-derived thingamajigs hinder absorption even from good vegan food sources of iron? Well, yes, they do, but other plant constituents, like vitamin C, and bioflavonoids, aid non-heme iron absorption so eating whole foods and fresh foods means that things often balance out.
Do We Really Need Iron Supplements?
Interestingly, the lower levels of iron stores observed in some vegans has actually been hypothesised to be a good thing as excess iron is increasingly connected to chronic disease, possibly through oxidative stress. Indeed, a number of pieces of research have failed to find negative effects of lower iron and zinc stores in vegetarians in developed countries. The current thinking in nutrition circles is that it is important to have good intake of iron during the early years but to ensure iron intake stays adequate but not excessive in later life. Of course, as with most nutritional advice this depends largely on the person, their individual health concerns, the food available to them, how the food is processed, and even the ground in which that food is grown.
Are Vegans Deficient in Iron?
Several studies, including one by Alexander et al (1994), found that although the intake of iron was significantly higher in vegetarians compared to their omnivorous peers their actual iron levels were much lower. Ensuring adequate intake to meet levels recommended for the general populace is, therefore, insufficient for most vegetarians and vegans, particularly it seems for men. There has been plenty of focus on low iron levels in female vegans and vegetarians and some of the pejorative terms thrown around about vegans are likely based on this assumption of instant anaemia when cutting out meat.
Pasty vegans who faint and swoon and are generally sickly are certainly far removed from my experience of veganism but, as with all things, stepping outside the norm draws attention to the unfortunate cases where ill health does arise.
Omnivores may be able to put less thought into getting sufficient iron in their diet, and its absorption from iron rich foods, but this does not automatically translate into abundant health.
Improving Non-Haem Iron Absorption in a Vegan Diet
A more all-encompassing discussion of iron and veganism is in the works and will be published over in the nutrition section of The Tasty Vegan site but for now let’s just have a quick look at some great vegan food sources of iron and ways to boost bioavailability and iron absorption as a vegan.
Vitamin C and Iron
Ascorbate supplementation is a key way to increase iron bioavailability in a vegan diet, with Sharma and Mathur concluding that 500mg of ascorbic acid twice daily (once with lunch and once with dinner) had a more significant effect on increasing various measurements of iron status than iron supplementation itself. Whilst supplements of vitamin C can be helpful you might also want to think about drinking a glass of orange juice with your meal or having a little extra (lightly!) steamed broccoli, zucchini, or other low oxalic acid vegetable as an accompaniment.
Enemies of Iron Absorption
A basic rule of thumb for increasing iron bioavailability from vegan diets is to avoid TOPHYPOS. This lovely little neologism of mine means:
- Tannins – from tea, coffee, yerba mate guarana, beer, grapes (and wine), some berries, dates, eggplant, kiwis, pomegranate, walnuts, alfalfa, chocolate, carob, and loads of other things like herbs and spices.
- Oxalic acid – found in spinach (which is also a good iron source, ironically), rhubarb, amaranth, cassava, chives, parsley, purslane, chocolate (sorry), and even beet leaves.
- Phytates – found in legumes like soy (unless well fermented), as well as in wholegrains and bran (bread fanatics beware).
- Phosphates – found at high levels in fizzy drinks and soft drinks that are made tart and acidic through the addition of phosphate derivatives. Also present in wholegrains, and in fortified beverages as tricalcium phosphate (so don’t drink your soy milk with a meal you’re eating to boost iron levels).
After looking at this list it might seem pretty much impossible to ever devise a vegan meal that’s high in iron and low in inhibiting factors for absorption but the fact is that a varied diet usually has you covered and you can quickly learn a few tips and tricks to improve your iron status as a vegan. You don’t need to memorise a list of vegan food sources of iron or never drink tea or soymilk with your meals, just try to include lots of different foods, including a few rich food sources of iron and think about avoiding the main culprits that block non-haem iron absorption when specifically including these iron-rich foods. New vegans concerned about nutrition, don’t fear, after a while these things become a reflex akin to your brain quietly muttering to itself that you’ll wait a while between your dinner of a tomato lentil casserole with steamed broccoli before having that beer/tea/can of soda.
Great Vegan Food Sources of Iron
Vegan food sources of iron range from cooked soybeans at 8.84mg of iron per cup to radishes with just 0.02mg of iron per radish. Lots of foods fall somewhere in-between these measurements and the list of vegan sources of iron below starts with those highest in iron content and gets down to those providing around 2mg per standard portion size. All the data is taken, as always, from the USDA nutrient tables, filtering out the mentions of enriched foods from Kellogg (which always seem to top lists!) and cow products.
- white beans
- canned tomatoes
- kidney beans
- jerusalem artichokes
- pearl barley
- oat bran
- buckwheat flour
- chickpeas (Team Chickpea!)
- baked beans
- lima beans
- navy beans
- potatoes (with skin!)
- black beans
- pinto beans
- turnip greens
- beet leaves
- baked beans
Clearly, there are lots of other tasty vegan foods providing a decent contribution to iron intake but these are some of the best so make sure to keep your diet varied, minimise those things that block iron absorption and think about adding in a little extra vitamin C if your doc tells you your iron levels are too low. Being vegan does not mean an automatic trip to anaemia central but there are those predisposed to anaemia, such as Coeliacs, those with other gastrointestinal issues, bleeding stomach ulcers, people taking certain medications, and new vegans and vegetarians who haven’t yet had time for their digestive system to upregulate non-haem iron absorption which, like zinc absorption, takes a few months to work itself out.
Veganism and Anaemia
Above all, if you do think you might be anaemic or at least low in iron, get it checked before supplementing as excess iron can do more harm than good. Some vegans get all shy about being anaemic as they feel they’re letting Team Vegan down – don’t, your health is the important thing and dogmatic denial of the very real problems that can arise in both vegan diets and omnivorous diets does no one any favours. Some symptoms of iron-deficiency anaemia include breathlessness upon even minor exertion (climbing stairs, for example), a propensity for bruising, glossitis (tongue swelling), tiredness and weakness, poor concentration and difficulties studying or working, lowered immunity and resistance to infections, and difficulty maintaining body temperature.
Most vegans probably have an abundance of iron-rich vegan foods in their diets but it might be that you drink tea with every meal, eat nothing but sandwiches, or drink fizzy drinks constantly. Iron intake meeting recommendations for the general population doesn’t really apply for vegans as non-haem iron is harder ot absorb so give your body a helping hand and eat more of these good vegan sources of iron alongside foods that help absorption.
Alexander D, Ball MJ, Mann J., Nutrient intake and haematological status of vegetarians and age-sex matched omnivores. Eur J Clin Nutr. 1994 Aug;48(8):538-46.
Hunt JR., Moving toward a plant-based diet: are iron and zinc at risk? Nutr Rev. 2002 May;60(5 Pt 1):127-34.
Hunt JR., Bioavailability of iron, zinc, and other trace minerals from vegetarian diets. Am J Clin Nutr. 2003 Sep;78(3 Suppl):633S-639S.
Craig WJ., Iron status of vegetarians. Am J Clin Nutr. 1994 May;59(5 Suppl):1233S-1237S.
Kim MK, Cho SW, Park YK., Long-term vegetarians have low oxidative stress, body fat, and cholesterol levels. Nutr Res Pract. 2012 Apr;6(2):155-61. Epub 2012 Apr 30.
Sharma DC, Mathur R., Correction of anemia and iron deficiency in vegetarians by administration of ascorbic acid. Indian J Physiol Pharmacol. 1995 Oct;39(4):403-6.