This week in the nutrition class I’m teaching we are covering the basics of the importance of iron metabolism and function in the body so I thought for this Wellness Wednesday I would share it with you all!
Iron Functions
- Oxygen Transport (part of hemoglobin and myoglobin)
- Energy and Metabolism
- Immune System Function
Iron Status Indicators
Serum Iron
Indicates the amount of iron in the blood. Sometimes people may have a normal serum iron value, but are iron deficient. Therefore, it is important to use multiple blood tests when determining iron status.
Ferritin
Indicates the status of iron stores, a low ferritin value is the first indicator of iron deficiency.
Whenever I work with a new client, I always want to know what their ferritin values are especially if they are having issues recovering from exercise, feeling fatigued or generally not feeling well. Symptoms of low ferritin can very closely mimic symptoms of a low thyroid function, including intolerance to cold and inability to lose weight. I’ll never forget one client I worked with at the gym, we did her resting metabolic assessment and the whole time she was shivering like mad. The results came back very very very low so we immediately ran a thyroid panel and a ferritin value. Her thyroid levels weren’t perfect but her ferritin value came back at 9 (the reference range is 12-290 at some labs), well below the already way to wide reference range. Her husband was a doctor so she began supplementing under his guidance and got better quickly.
I’ve also worked with several clients who benefited from slight supplementation to get their levels closer to or above 50. In fact, I personally recently started supplementing after discussing it with my doctor even though my levels were 55 the last time I had it checked (in general it’s a good idea to get second opinions when treating yourself, even if you are a medical professional). I have a longstanding history of anemia, bruise SUPER easy, have super low body temperature (consistently under 97), a diet high in foods that inhibit absorption of iron and a few other things that suggested that supplementing might help. I’ll do this for 30 days then recheck to ensure it doesn’t go up above recommended levels. It’s important to only supplement with iron under supervision of a professional as it can have some brutal side effects and iron overload can cause a whole host of serious problems.
Total Iron Binding Capacity or TIBC
Measures how many sites on the iron transport protein transferrin, are available to carry iron. Serum iron and TIBC are then used to calculation transferrin saturation.
Transferrin saturation
Indicates the amount of iron bound to transferrin. Declines in transferrin saturation indicate lower levels of circulating iron.
Hemoglobin
Is the oxygen carrying protein on a red blood cell. Iron is necessary to activate the hemoglobin protein. If you do not have enough iron, your ability to produce red blood cells is impaired. As a result, you we see a decrease in red blood cell size and number.
Hematocrit
Measures the percentage of the volume of blood made up of red blood cells. The measurement affected by the size and number of red blood cells.
Factors Affecting Iron Regulation
Body Status
- Levels of iron n the body will determine the percentage absorbed. It is currently thought that we lack regulatory processes to excrete iron once absorbed, therefore the body the body regulates iron status by limiting absorption.
- Rare genetic conditions may under or over regulate iron levels in the body. Most common is hemochromatos is a condition in which iron absorption leads to toxic levels of iron in the blood. Regularly having your iron levels screened should be enough to detect this if you have it, you will also likely have a family history.
Type of Iron
- Heme Iron found in animal sources like red meat, liver, poultry, eggs, etc is 3x as adorable as those found in plant sources (about 30% will be absorbed).
- Non-heme iron found in vegetables, beans, and fruits is much less adorable, only about 10% of intake will be absorbed.
Enhances Iron Absorption:
- Animal Protein
- Vitamin C
- Stomach Acid
Decreases Iron Absorption
- fiber
- phytates/oxlates (compound found in certain vegetables, beans and grains)
- tannins/polyphenol (tea, coffee and wine)
- other minerals such as calcium and zinc
Who is at risk of low iron levels?
- elderly
- vegetarians
- low calorie diets
- women (especially during pregnancy/lactation)
- children (especially with high milk consumption)
- GI disorders
- gastric bypass patients
- chronic antacid use
- chronic blood loss
- runners (damage to mini blood vessels in feet)
I’ve recently become aware that just about everyone in the population who is isn’t supplementing is at risk for low iron levels. We tend to lead an antacid popping, calorie restricting, meat demonizing, veggie shunning, fiber supplement slamming type of lifestyles. I know I’ve been there, that’s why I’ve been anemic in the past, no body is really immune so I’ve started making it part of the standard things we look at for Hungry Hobby RD clients. That being said, iron overload is just as serious if you supplement without supervision, so make sure you get advice from a trusted health professional. Like I said, I even discussed my results with another professional before starting a supplement regimen!
Foods Rich In Iron
If you are truly looking to increase (or decrease) intake of iron then these are the foods you need to amp up/avoid. As mentioned earlier, iron is also found in vegetables, beans, and some fruits but often is not significantly absorbable.
Meat and Eggs: Beef, lamb, ham, turkey (dark meat), chicken (dark meat), veal, pork, dried beef, liver, liverwurst, eggs
Seafood: shrimp, clams, scallops, oysters, tuna, sardines, haddock, mackeral
[Tweet “Iron Foods, Functions and Facts #WellnessWednesday via @hungryhobby”]
Other Women’s Health Related Posts:
- Recovering from 5 Years of Amenorrhea
- Post-Pill Amenorrhea Update (4 months later)
- Seed Cycling for Amenorrhea, PMS, or irregular periods
- How to Make Your Hormone Works for You (what to eat/how to train)
- Iron Foods, Functions, and Facts (related)
- My friend Ashley wrote an ebook called Fit & Fertile (affiliate link) about her experience with Amenorrhea as a Group Fitness Instructor and what she did to get pregnant naturally. Her experience was different t n mine, but similar in some ways as well. Either way, it was definitely a comforting read.
Totally sharing with my friend who’s concerned her tween isn’t getting enough iron! GREAT post Kelli! Any specific tips for tweens?
Ohhh that is a great question Serena! One of the most common things I see tweens doing is cutting out entire food groups limiting their nutrient intake overall! Keep a well varied diet and you should be okay! Protein and produce at every email should supply enough iron and vitamin c !
Another Wellness Wednesday done superbly well.
Thanks for sharing, Kelli
Thank you Patrick!
I found your blog through carrotsncake. I found out my iron is low today. What do you recommend for a supplement?
Hi Molly, welcome! I’ve had good success with iron bysglinate (gentle iron). However, refer to your doctor or health care provider to find out how much. When supplementing with iron you should be closely monitored since taking too much can be dangerous. Hope that helps!
Another great post by you! Love it.