I’ve been a non-meat eater for nearly 30 years and have never before had low iron levels. That’s because I eat a wide range of foods and always have a vitamin C drink (smoothie, cordial, fruit juice) with my main meals which helps iron absorption. I suspect my current low iron status is down to the drugs I need for my GERD, the bleeding in my pelvis due to my endometriosis or possibly some kind of bleeding going on in my stomach (it’s certainly painful enough). However, because I’ve changed my diet and gone “low histamine” in the last 4 years I wanted to take a closer look at the foods I’m now eating, just to make sure I was still getting enough iron in my diet.
Menstruating women need approx 14-15mg of iron daily. Men and post-menopausal women need 8-10mg. However it’s impossible to know how much iron our bodies are taking in because:
- iron content isn’t listed on food labels.
- iron absorption can be affected by drugs, stomach issues, illnesses etc.
- iron absorption depends on your existing iron stores.
- some foods help iron absorption, eg Vitamin C, acids and sugars, and some foods hinder iron absorption, eg tanins (in tea) and phytates (found in whole grains, nuts, seeds and legumes).
- iron is absorbed by the body differently depending on whether the food comes from a plant or an animal. Plant sources (non-heme iron) make up around 90% of the iron most people eat and animal sources (heme iron) make up around 10% of the iron most people eat. However, the body absorbs heme iron much better than non-heme iron.
In reality, the process by which the body utilizes iron is complex and it’s just not as simple as “oh for heavens sake eat a steak!”
I did a bit of Googling and found sensational headlines like “pistachio nuts contain 4 times the level of iron than other nuts”. Excellent, I love pistachios! However it wasn’t actually true. I sourced the iron content of foods from the United States Dept of Agriculture’s Food Composition Database (which is excellent) and discovered that Pistachio nuts actually have less iron than, for example, Cashew nuts so I’ve no idea where these headlines have come from.
Meat is widely touted as being the best source of iron. However, a skinless cooked chicken breast contains 1mg iron whereas 2 slices of unfortified white bread contains 2mg iron! It’s then you have to bear in mind that the bread is less easily absorbed than the chicken, but by how much no-one knows. Dairy is also widely purported to be high in iron, but according to the Database a ½pint (275ml, 1 cup) serving of milk has hardly any iron in at all and a large 100g serving of grated mozzarella cheese only 0.44mg. Balance that against a 2 tblsp serving of sunflower seeds which contain 1.57mg iron and I know which I’ll be eating more of in future.
I wrote down everything I ate over a few days and added up the total iron content, which came to between 18-20mg of iron per day. As mentioned, though, nearly all of my iron comes from non-animal sources so I’ve no idea how much iron I’m actually absorbing but I think on balance I’m consuming enough for my diet to not be the cause of my iron deficiency.
There were shock findings in my little research project which I wanted to share with you:
- Treacle is high in iron. I use treacle when making my gingerbread and according to the Database 1 slice of home-made gingerbread contains over 2mg iron. Way-heyyy!
- Puff pastry is high in iron. Who knew! A 150g slab of cooked puff pastry contains nearly 4mg iron, which is huge. I’ve always felt guilty about eating puff pastry because of its high butter/fat content but it’s a positive health food 😉
- I’d read that seeds are high in iron and this turned out to be correct. Dried chia seeds are top with a 1oz (30g, 2tblsp) serving containing 2.19mg. A 1oz (30g) serving of Sunflower seeds has 1.57mg and a 2 tsp (10g) serving of Sesame seeds has 1.31mg. An easy way of eating more seeds is to buy seeded bread, or to crush the seeds and add them to smoothies.
- There isn’t as much iron in meat as I’d been led to believe unless you regularly eat wild bear or bison. A restaurant style sirloin steak has 4.27mg iron but a pork chop only 1.67mg and a skinless chicken breast a mere 1mg. A salmon fillet has 1.59mg. Bear in mind though that more of the iron from meat is absorbed by the body than iron from other sources.
- I worked out my home-made tomato-less baked beans contain a whopping 5mg iron per serving! That’s because beans are high in iron but more importantly I make them with treacle.
It’s been interesting, if a bit confusing, looking at iron in foods and I realize that much of the information widely given is either incorrect or at the very least a bit misleading. The fact that milk is so low in iron I found shocking, especially when we’re told dairy is a good source of the mineral, and most meat isn’t as high in iron as we’re lead to believe. My confusion came when looking at foods such as beans, nuts, seeds and lentils, which are good sources of iron but also contain phytates which hinder iron absorption, so we have no idea how much of the iron is actually being utilized. Taking Vitamin C with a meal, eg. fruit juice, to help iron absorption still seems like good advice but I discovered you have to be careful which fruit you squeeze. A small study found that dark juices such as prune and red grape may actually hinder iron absorption, so are best avoided.
If you want to check your own diet for iron content I found these sites helpful:
- United States Dept of Agriculture’s Food Composition Database
- SELFNutritionData – enter the food you want to check in the search box on the top right.
- The Ferralet90 website which uses the same data as the Dept of Agriculture’s website but in easy-to-use categories and only the most popular foods. Do bear in mind this site is selling a product!