Iron is an essential mineral for the human body. Athletes especially should pay extra attention to ensuring sufficient iron intake and absorption. This is how to make sure your plant-based diet is rich in iron.
Iron is an important mineral for the human body for different functions. Iron plays an important role in building new red blood cells which deliver oxygen to the bodies’ tissues. Iron is also needed for energy maintenance, immunity and DNA synthesis. Iron deficiency is common among endurance athletes, especially women, who have increased loss of red blood cells via bleeding, higher turnover rate due to mechanical break down of the cells and a higher rate of iron-rich mitochondria. Decreased iron stores can eventually lead to iron deficiency anaemia where the size and amount of haemoglobin and red blood cells are decreased. This leads to poor oxygen supply to tissues (like skeletal muscles) which in turn limits their work capacity. Anaemia’s symptoms include fatigue, pallor, shortness of breath, dizziness, poor tolerance of exercise, weakness and rapid heartbeat. Iron deficiency without anaemia has also been shown to cause reduced endurance capacity, increased oxygen consumption and impaired adaptation to endurance exercise.
Iron and a plant-based diet
Vegan and vegetarian athletes are in a greater risk of iron deficiency and anaemia due to the form of iron found in a plant-based diet. Omnivores, vegetarians and vegans usually do get the same amount of iron from their diet but the form of iron plays an important role in how the body can use it. The main source of iron in a plant-based diet is in non-haem form when in animal products it is of haem form. Non-haem iron is less well absorbed from the gut than haem iron. Also, the vegan and vegetarian diets often contain nutrients like polyphenol tannins (found in coffee, tea, and cocoa) and phytates (found in whole grains and legumes) which reduce iron absorption from the diet. The human body can usually adapt to a variation of iron intake from the diet by regulating the amount of absorption and secretion from the gut, but if the turnover of iron greatly exceeds the amount gotten from food for longer periods of times, the iron stores will eventually be used and iron deficiency and anaemia may occur.
The daily recommendation of iron for men aged 19-50 is 8 mg and women 18 mg. The best way to get enough iron during the day is to make sure to eat iron-rich foods during each meal. Vitamin C enhances absorption of iron when consumed at the same time with iron so it is recommended to eat for example an orange for dessert. In addition, one can try to avoid consumption of high-phytate foodstuffs like coffee and tea which inhibit the absorption of iron. Athletes who are prone to developing iron deficiency should consider iron monitoring by blood tests. Sometimes iron supplements are needed to stabilize the balance if the deficiency has developed too far.
Iron-rich plant-based foods
There are some good sources of iron in the plant field that you can find in the list below. The low-FODMAP ingredients are written in bold.
TOFU, 125g: 6.8 MG (38%)
SPINACH, COOKED, 1 CUP: 6.4 MG (36%)
SOYBEANS, COOKED, 1/2 CUP: 4.4 MG (24%)
SWISS CHARD, COOKED, 1 CUP: 4.0 MG (22%)
TEMPEH, 125 g: 4 MG (22%)
BLACKSTRAP MOLASSES, 1 TABLESPOON: 3.6 MG (20%)
LENTILS, COOKED,150 g : 3.3 MG (18%)
POTATO, COOKED with skin, 1 LARGE: 3.2 MG (18%)
TURNIP GREENS, COOKED, 1 CUP: 3.2 MG (18%)
COCONUT MILK, 2 dl, 3,2 MG (18%)
QUINOA, COOKED, 1 CUP: 2.8 MG (16%)
BEET GREENS, COOKED, 1 CUP: 2.7 MG (15%)
TAHINI, 2 TABLESPOONS: 2.7 MG (15%), low-FODMAP when consumed 1 tbsp
PEAS, COOKED, 100 g: 2.5 MG (14%)
BLACK EYED PEAS, COOKED, 1/2 CUP: 2.2 MG (12%)
CASHEWS, RAW OR ROASTED, 1/4 CUP: 2.1 MG (12%)
KIDNEY BEANS, COOKED, 1/2 CUP: 2.0 MG (11%)
CHICKPEAS, COOKED, 1/2 CUP: 1.8 MG (10%)
BLACK BEANS, COOKED, 1/2 CUP: 1.8 MG (10%)
BOK CHOY, COOKED, 1 CUP: 1.8 MG (10%), low-FODMAP when consumed 75 g
BULGUR, COOKED, 1 CUP: 1.7 MG (10%)
Interested in enhancing your iron intake? Try this iron-rich stew recipe.
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