Iron deficiency is a common issue these days and while there is an abundance of food sources and supplements some are still not enhancing their levels sufficiently. Most of the treatment is aimed at eating as much iron rich foods as possible and using iron supplements but what some are forgetting are the things that block or inhibit the absorption of iron.
While we advocate to increase your diet full of Iron sources of the below:
- Heme: animal sources lean red meat (try not to overcook or stew or casserole), white meat (poultry, turkey), oysters, clams, eggs, tinned sardines in tomato
- Non Heme: beetroot, green leafy vegetables, almonds, apricots, avocado, sunflower and pumpkin seeds, molasses, brewer’s yeast, pulses cooked in tomato, maca powder, spirulina powder, adzuki beans.
We need to ensure that we are not blocking our absorption of iron at the same time the following Iron dietary influences include:
Please note that this is more essential in people with low iron issues.
- tannins (wine, coffee has been shown to reduce iron by 40% and tea reduced iron by 60%)
- avoiding burnt (charcoal) foods
- avoid calcium rich foods at the same meal as calcium may reduce iron absorption by 70% (almonds, anatacids, broccoli, calcium supplements, cheese, figs, milk, tinned salmon, yoghurt)
- oxalic acid avoid iron/iron rich foods at the same meal (beetroot, kale, wheat bran, spinach, chard, chocolate, berries)
- zinc and manganese supplements may compete with iron absorption
Other factors affecting iron absorption include:
- No strenuous exercise or donating blood
- Fast digestive transit time (diarrhoea)
- Malabsorption issues
- Inadequate digestive secretions like achlorhydria
- Medications like antacids and proton pump inhibitors like nexium as sufficient stomach acid is required to absorb iron.
The take home message here is to be mindful when you are trying to improve your iron stores, it is important to eat a diet with a wide variety of foods and if you are trying to improve your iron status then separate the inhibiting foods and supplements by 2 hours.
Braun L & Cohen M. 2007 “Herbs & Natural Supplements: an evidence-based guide 2nd edition” Elsevier, Australia.
Kaltwasser JP1, Werner E, Schalk K, Hansen C, Gottschalk R, Seidl C. 1998 “Clinical trial on the effect of regular tea drinking on iron accumulation in genetic haemochromatosis.” Gut. 1998 Nov;43(5):699-704.
Roughead ZK1, Zito CA, Hunt JR. 2005 “Inhibitory effects of dietary calcium on the initial uptake and subsequent retention of heme and nonheme iron in humans: comparisons using an intestinal lavage method.” Am J Clin Nutr. 2005 Sep;82(3):589-97.