Iron is a trace mineral found in EVERY cell in our body. It plays an important role in energy production, fetal development as well as red blood cell production. There are two forms of iron: heme and non-heme.
Heme iron carries oxygen from the lungs to the body's tissues through hemoglobin. Myoglobin holds the oxygen in the cells of the muscles. Heme iron is the most bioavailable form of iron. This means the body can absorb it and use it more easily than non-heme iron. Sources of heme iron are meat, poultry, and fish.
Non-heme iron is much less absorbable but there is much more of it in the foods we eat than heme iron. Therefore, it contributes more in meeting our iron needs. Sources of non-heme iron are legumes, fruits, and vegetables. Studies have shown that meat enhances the absorption of non-heme iron.
Symptoms of iron deficiency
Cold hands and feet
Tongue inflammation or soreness
Craving for ice, dirt, or other non-nutrition substances
Fast heartbeat, chest pain
Shortness of breath
Major hindrances to iron absorption are:
Phytic acid is a natural substance found in plant seeds that hinders the absorption of iron, zinc, and calcium. It is often referred to as an antinutrient because it works against the body. For those following a healthy diet, phytic acid is not a big problem. But, for those NOT following a healthy diet, malabsorption and malnourishment can occur.
All edible seeds, grains, legumes, and nuts contain phytic acid in various amounts, and small amounts are also found in root vegetables and tubers. Phytic acid can be reduced by soaking, sprouting, or fermenting.
In other words, common, everyday foods are hindering nutrient absorption simply because of the way they are prepared. Soaking nuts, seeds, and legumes (like beans and peanuts), drastically change their level of benefit for our bodies. Making your own bread out of a handful of ingredients and soaking your flour overnight is going to make eating bread a beneficial food rather than something thought of as "not good for you."
This post has tons of information about soaking grains, legumes, nuts, and seeds from The Nourishing Home.
Here's a great post about sprouting just about anything from Wholefully.
Cultured Food Life is one of my favorite websites to learn about fermenting.
Polyphenols are antioxidants found in fruits and vegetables. The more colorful it is, the more polyphenols it has. They are beneficial to our health because they neutralize free radicals and reduce inflammation. However, when taken in the form of supplements, they actually work against the body by hindering or limiting iron absorption.
Many of the nutrients in supplements are synthetic, which is not necessarily a bad thing. However, people with particular gene mutations cannot absorb some synthetic nutrients. Supplements often give people a license to continue with their poor diet rather than working to incorporate better food into their lives. If supplements are the only way you're receiving nutrients and your body cannot absorb some nutrients, then you will be depleted even if you take your supplements every single day.
Calcium has been shown to inhibit iron absorption in people taking high doses of calcium. I highly recommend a diet in calcium-rich foods instead of supplements. It is recommended, however, that if you increase calcium with supplements, iron should also be increased, specifically in the form of iron-rich foods. It is also recommended that, since most iron is received at the three main meals, it is best to take calcium supplements at bedtime.
According to DrAxe.com, these are the top foods with heme and non-heme iron :
Choose nutrient-dense foods over supplements every chance you get. Your body will thank you!
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Office of Dietary Supplements - Iron. (n.d.). Retrieved September 26, 2020, from https://ods.od.nih.gov/factsheets/Iron-Consumer/
Link, R. (2020, January 23). Top 15 Iron-Rich Foods. Retrieved September 26, 2020, from https://draxe.com/nutrition/top-10-iron-rich-foods/
Arnarson, A., BSc, Ph.D. (2018, June 28). Phytic Acid 101: Everything You Need to Know. Retrieved September 26, 2020, from https://www.healthline.com/nutrition/phytic-acid-101
Gotter, A. (2019, March 08). Polyphenols Food List: Seasonings, Berries, and More. Retrieved September 26, 2020, from https://www.healthline.com/health/polyphenols-foods
Barton, J. C., Conrad, M. E., & Parmley, R. T. (1983, January). Calcium Inhibition of Inorganic Iron Absorption in Rats. Retrieved September 26, 2020, from https://www.gastrojournal.org/article/S0016-5085(83)80171-1/pdf
Hallberg, L. (1998, July). Does calcium interfere with iron absorption? Retrieved September 26, 2020, from https://academic.oup.com/ajcn/article/68/1/3/4666003
Berner, L., & Miller, D. (2003, October 02). Effects of dietary proteins on iron bioavailability-A review. Retrieved September 26, 2020, from https://www.sciencedirect.com/science/article/abs/pii/0308814685901025
Petre, A. (2019, July 08). What Are Polyphenols? Types, Benefits, and Food Sources. Retrieved October 01, 2020, from https://www.healthline.com/nutrition/polyphenols
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Iron deficiency anemia. (2019, October 18). Retrieved October 01, 2020, from https://www.mayoclinic.org/diseases-conditions/iron-deficiency-anemia/symptoms-causes/syc-20355034