Iron is a mineral that the body needs to grow and develop. Iron helps make healthy red blood cells that transport oxygen throughout the body. Iron is critical for normal immune function. Iron is the structural component of hundreds of essential molecules. Iron assists antioxidant enzymes.
Iron deficiency is the number one nutritional deficiency in the United States. According to the National Health and Nutrition Examination Survey (NHANES) II. iron deficiency occurs in approximately 11% of women,1-2% of all adults, and in approximately 12.5% of athletes.
It is the No. 1 cause of anemia in athletes. Iron deficiency rates (with or without anemia) in athletes range from 20-50% in women and 4-50% in men.
Iron deficiency anemia occurs when the body does not have enough healthy red blood cells due to a lack of iron in the body.
Two forms of dietary iron
Heme iron is better absorbed than nonheme iron; the absorption of nonheme iron is enhanced by vitamin C.
National dietary surveys indicate that iron is under-consumed by adolescent and premenopausal females.
Iron recommendations vary between adults and teens
What causes iron deficiency
Iron losses occur from blood loss in the gastrointestinal (GI) tract, microscopic losses in urine, hemolysis of red blood cells (RBC) breakdown, menstrual cycle, sweat loss, and intense exercise.
Non-steroidal anti-inflammatories (NSAIDs) like ibuprofen, Advil, and naproxen deplete iron and folate. Frequent use of medications with GI side effects such as aspirin and non-steroidal anti-inflammatories like ibuprofen or naproxen can cause or worsen iron deficiency.
Physical activity particularly high intensity and endurance types increase iron losses by as much as 70% when compared to sedentary populations. Athletes lose more iron due to heavy sweating as well as increased blood loss in the urine and GI tract.
Causes range from a variety of health issues to simply overtraining or even lack sleep. Any athlete that experiences a decrease in training or performance coupled with symptoms should seek out their primary care doctor for further testing and analysis.
Signs and symptoms of low iron
Weakness, fatigue, decreased physical endurance, feeling hot or cold, diminished immune response, alterations in energy levels, cognitive performance, and overall behavior. Iron deficiency is not the only cause of these common symptoms.
Iron in meat, fish, and eggs is easily absorbed by the body but the iron in plant sources is attached to phytates that bind iron in foods.
Following a plant-based diet and limiting animal iron sources can be a challenge. As a practitioner, I meet the client where they are at but do share that consuming animal protein will offer greater iron to support their health and performance goals.
Guidance on increasing iron as a plant-based athlete
Pair leafy greens (bok choy, kale, spinach) with a source of vitamin c (broccoli, strawberries, bell peppers, and kiwi) –This can increase the absorption by up to 67%! (3)
Cooking food in cast iron or stainless steel cookware also aids in iron absorption (cook all veggies and protein in the cast iron skillet)
Eat more beans, lentils, edamame, baked potatoes, and Iron-fortified oatmeal (higher sources of iron).
Drink tea or coffee separately from an iron-containing meal or snacks. Caffeine inhibits iron absorption.
Additional ways to combine vitamin C-rich foods with beans
Drain a can of pineapple cubes and add them to canned baked beans
Toss cooked black beans with shredded cabbage in your favorite coleslaw recipe
Sauté red peppers and onions in olive oil and stir into the white navy or Great Northern beans (cast iron pan)
Add any type of cooked beans to a spinach or kale salad with pineapple or fruit
Add fatty fish into your diet 1x/week (3 oz of salmon) or oysters (also a rich source of iron)!!
Blend up leafy greens and fruits rich in vitamin C with your smoothies (you can even add beans – I promise it is a neutral taste)
Eat more lean red meat, chicken, seafood, beans, lentils, edamame, baked potatoes, and Iron-fortified oatmeal (higher sources of iron).
Sauté red peppers and onions in olive oil and stir into the white navy or Great Northern beans (cast iron pan)
In a skillet prepare steak, spinach, or collard greens paired with berries (best way to increase iron)
When young athletes or adults we start with simple guidance to help increase iron
Set meal goals: 4 oz of flank steak 2-3 x/week paired with leafy greens
Snack idea: A side of roasted chickpeas paired with pineapple
Snack idea 2: A 1/2 cup of mixed berries paired with fortified oatmeal
Before taking an iron supplement to correct an iron deficiency you should contact your physician and work with a dietitian to raise iron levels properly. It is best to work closely with a dietitian to ensure you or your young athlete is getting the proper amount if iron to avoid health and performance consequences. We have worked with hundreds of teen athletes and plant-based adults that have struggled with low iron. We can help you too! Contact us for student-athlete coaching or for a virtual presentation for your sports team.
In good faith, health, and athletic performance,
Wendi Irlbeck, MS,RDN,LD,CISSN
Citations and resources to learn more:
National Health and Nutrition Examination Survey (NHANES) II.
Hurrell, R., & Egli, I. (2010). Iron bioavailability and dietary reference values. The American journal of clinical nutrition, 91(5), 1461S–1467S. https://doi.org/10.3945/ajcn.2010.28674F
Goldstein, J. L., Chan, F. K., Lanas, A., Wilcox, C. M., Peura, D., Sands, G. H., Berger, M. F., Nguyen, H., & Scheiman, J. M. (2011). Hemoglobin decreases in NSAID users over time: an analysis of two large outcome trials. Alimentary pharmacology & therapeutics, 34(7), 808–816. https://doi.org/10.1111/j.1365-2036.2011.04790.x
Hallberg, L., & Hulthén, L. (2000). Prediction of dietary iron absorption: an algorithm for calculating absorption and bioavailability of dietary iron. The American journal of clinical nutrition, 71(5), 1147–1160. https://doi.org/10.1093/ajcn/71.5.1147
Koehler, et al. Iron status in elite young athletes: gender-dependent influences of diet and exercise. Eur J. Appl Physiology, 2011.
17-year-old, Jenkins comes strutting out of the weight room after he just crushed a workout living his strongest, healthiest, and injury-free life. While walking out of the weight room Jenkins is using Nutrition with Wendi’s recommended “25-50-30 rule” and is downing a shaker bottle with chocolate milk and creatine paired with a banana. Jenkins is a smart kid and has focused on proper sleep, hydration, eating well, and managing his stress while training hard. But of course, many make comments like, “You know that powder he is mixing in there is steroids right? One of my parent’s friends said his coach has been encouraging the use of anabolic steroids for years!” YIKES RIGHT??
Ever heard this crazy misinformation before? Yes, me too. It has spread like wildfire. It is even more gut-wrenching when it’s spread by doctors, trainers, health care professionals, influencers, or random people on the internet that know very little about science, sports performance, or even what creatine is. Insert facepalm. Good news! I am here to dispel those myths and provide the science to help combat the misinformation that is so toxic.
Creatine is one of the most effective ergogenic aids for adult athletes and is safe. Creatine effectively increases lean mass, strength, power, speed, and exercise capacity (1). But what about youth athletes? I have had several high school coaches and concerned parents of youth athletes ask me questions like, “Is creatine safe for my kids? Should my female athletes be using creatine?” In almost every conversation, my first response is, “It depends.” Just like any other question I get, nutrition-, health-, fitness- or performance-related, it should be individualized. Creatine, however, is beneficial to all populations according to the science outlined in this article. As a registered dietitian, I strongly promote a “food first” and back-to-basics philosophy. For more information on healthy eating and performance nutrition, see a previous blog here. I empower anyone working with youth athletes to use the guidance in this article when considering “to supplement with creatine or not.”
Creatine Monohydrate 101:
95% of creatine is found in skeletal muscle
The human body needs 1-3 g per day
Most creatine in the diet comes from animal products like meat, fish, & poultry
Creatine is a naturally occurring compound formed by three amino acids, making it a tripeptide (tri- meaning three) of the amino acids L-glycine, L-arginine, and L-methionine. Creatine is assembled in a two-step process that occurs in the kidneys and liver.
Creatine improves numerous factors including strength, power, sprint ability, muscular endurance, resistance to fatigue, muscle mass, recovery, cognition, and rate of muscle growth. Creatine is one of the most widely studied, proven performance enhancers available that also offers clinical benefits (4).
How does creatine work?
Creatine deposits high-energy phosphate groups in the form of phosphocreatine. This is given to adenosine diphosphate (ADP), regenerating it to adenosine triphosphate (ATP), the sole energy carrier in the human body, which can be called “energy currency” for cells to carry out their functions. For example, during conditions of short-term, high-energy demand activities (<30 seconds) with limited recovery time, ATP runs out quickly, which illustrates the importance of creatine stored in muscles in the form of creatine phosphate. This is explained here.
Since creatine phosphate restores ATP, it gives muscle cells the ability to produce greater energy. The greater creatine stores you have, the greater energy your muscle cells can yield during high-intensity exercise, thus leading to increased exercise performance. Even though the most well-documented and primary benefit is higher energy production, this mechanism also supports muscle gain and strength increases, as explained here.
Despite creatine being widely tested since the early 1900s with significant data supporting its effectiveness, it is widely misunderstood by many trainers, coaches, athletes, and concerned parents of high school athletes. Yes, it is 2021 and people still think creatine monohydrate is a steroid due to misinformation generated across social media and the general population (4).
Disregard the false, outlandish, disproven claims. I am referencing the silly fallacies like, “creatine will make you fat,” “creatine will cause liver, kidney, or bone injury,” “creatine will dehydrate you,” or my personal favorite, “creatine is a steroid that will also lead to baldness.” I know. What a bunch of nonsense. I addressed these fallacies in a previous blog, Creatine Not Just for Men or Muscle. Please go check it out if you are a female because creatine can help you improve your lean mass and lose that fat.
Antonio et al. published a phenomenal paper outlining the common questions and misconceptions regarding creatine use available for open access here (1). I highly recommend you read it and share it with anyone who may have creatine confusion disorder. I made that up, but you get my point. Creatine monohydrate is beneficial for many things beyond performance, which is not my opinion but sc!
Potential ergogenic benefits of creatine supplementation in adults (4):
Greater training tolerance
Increased sprint performance
Increased work performed during sets of maximal effort
Increased lean mass & strength adaptations during physical training
Enhanced glycogen synthesis
Increased work capacity
Increased anaerobic threshold
If you’re interested in my opinion as a dietitian and performance practitioner working with several athletes I highly recommend creatine. Creatine is like the Swiss Army knife of supplements! It can do so many things!
There is robust evidence to support the effectiveness of creatine in the adult population. Among children and adolescents, there is mounting evidence to support the therapeutic benefits of creatine supplementation as well as clinical and exercise performance. Available studies in the adolescent population involving high-intensity exercise training indicate performance benefits as well as no reported side effects (1,2).
In relation to performance, the International Society of Sports Nutrition (ISSN) has concluded that creatine monohydrate is the most effective ergogenic supplement available to athletes in terms of increasing high-intensity exercise and supporting lean body mass during training. The ISSN has also concluded CM is safe. (4).
Does creatine work in young athletes?
Regardless of the limited data on the teen population, creatine is likely safe, beneficial, and well-tolerated among youth athletes as evidenced by the available data (2).
Creatine supplementation improved time performance and strength in highly competitive swimmers (2,3).
Should my teen athletes be supplementing with creatine?
As always, food first, but creatine can be a safe and effective regimen for young athletes who meet the following criteria (1,5):
Consuming a well-balanced diet
Consuming a diet with a greater emphasis on plant proteins like soy and pea which do not provide creatine like animal proteins
Involved in high-intensity training, and competitive sports which include:
Combat Sports (MMA, wrestling, boxing, etc.)
It is always best practice that athletes of any age fully educate themselves by consulting with a registered dietitian nutritionist, certified sports nutritionist, exercise physiologist, or sports-focused physician before the use of any supplement. Similarly, any products used should be NSF International Certified for Sport to reduce the risk of consuming any harmful or contaminated products. Supplements are regulated but not as heavily regulated as pharmaceuticals. Please see the reasons to use NSF Certified for Sport products in a previous blog.
“The USADA recommends that athletes use only dietary supplements that have been certified by a third-party program that tests for substances prohibited in sport. The USADA is responsible for anti-doping education and testing for athletes in the U.S. Olympic and Paralympic Movements as well as the UFC.”
Therefore, all supplements used should be third-party tested for safety, purity, and compliance. For the sake of convenience and safety, you and your athlete can download the NSF Certified Sport app.
I preach food first, nutrient periodization, quality rest, good sleep hygiene, hydration, and appropriate training, all of which can be better enhanced using creatine monohydrate (CM). Based on the strongest science and studies, CM is the recommended form. CM is used in the studies. Therefore, it should be used in practice as well. I discussed the other forms in my guest appearance on Muscles and Management.
When to use creatine?
The science suggests creatine is most effective immediately post-workout when paired with protein and carbohydrate (7). Creatine consumed immediately post-resistance training is superior to pre-workout in terms of body composition and strength (7). The recommended dose is 3-5 g of creatine per day. Creatine can be used at any time of day. Creatine is safe and effective on rest days from exercise as well as training days. (Click here to follow on Instagram)
While CM is best paired with a carbohydrate-rich source (like oatmeal, whole-grain bread, rice, fruit, smoothies, or yogurt) to draw it into muscle cells, it can also be added to water or other beverages. A saturated cell is a happy cell! This supports recovery and muscle repair following resistance training.
Most creatine supplements are in powder form and must be used in warm water to support the dissolving process. CM will dissolve slowly in cold water and often ends up in the bottom of a shaker bottle, which won’t do any good if it doesn’t make it into your mouth! Creapure is a great brand to use and offers more explanation on dosing. Check it out here! No, I do not have a partnership or any affiliation with Creapure. I just want to share that they make a great product.
My female youth soccer players have integrated CM post-training with their tart cherry juice and chocolate milk. I have taken time to discuss the safety, use, and benefits with my youth athlete’s parents, coaches, and even their PE teachers. I have 50% of my youth athletes supplementing with CM. CM is always a conversation we have after we wrap up their 6-week Nutrition with Wendi Coaching Program.
Do I need to load?
No, you do not need to “creatine load”. In fact, many studies use a typical creatine dose of 5-10 g daily or smaller doses like the standard 2-3 g. However, if you desire to do a loading phase, it would look something like 20-25 g for 5-7 days followed by a maintenance phase of 5 g daily for 4 weeks, 2 weeks off, and then repeat. I do not have any of my athletes do this cycling as it is unnecessary. See the ISSN’s Position Stand for more on this (4).
Studies support the benefits of CM supplementation regardless of the dose. However, that does not mean more is better. If you are a vegetarian and new to using CM, you would benefit from saturating the muscles with CM, leading to an acute increase in strength and body weight via water retention. However, please refer to the experts and those I respect most in the field like Dr. Darren Candow, Dr. Tim N. Ziegenfuss, Dr. Scott Forbes, Dr. Jose Anotonio, Dr. Rich Krider, Dr. Eric Rawson, and others who can further provide the research they have been doing for the last few decades.
Please see another podcast in which I had the opportunity to speak about creatine in the youth population via the Big Time Strength podcast.
There is robust literature to support the beneficial effects creatine has on body composition, physical performance, injury prevention, recovery, brain health, and clinical use. Currently, there have not been any negative effects associated with the use of CM in both the adolescent and adult populations. Adolescent athletes under the age of 18, and even children as young as infants, can safely consume CM. There is zero evidence to suggest CM supplementation would cause harm, dehydration, cramping, or any other outlandish claims that have been disproven by Antonio et al., 2021, and others. Not incorporating a CM supplement would be a disservice to your athletes or even yourself!
Anyone looking to improve their health of any age or activity level can safely consume 3-5 g of creatine monohydrate immediately post-workout paired with a carbohydrate.
By supplementing with creatine monohydrate immediately following training, you’re able to support muscle growth and recovery, injury prevention, and overall health.
Yes, creatine is safe to consume if you are a teen athlete. Yes, you should use creatine monohydrate.
No, creatine is not a steroid. No, creatine will not cause baldness. No, creatine will not dehydrate you. No, creatine will not cause cramps. No, creatine will not decrease your bone mineral density.
If you have a beating pulse, then creatine monohydrate is for you!
Sports physicians, athletic trainers, coaches, performance nutritionists, and others working with youth athletes should provide the best guidance to teen athletes based on the available science to support their principal interests. Kids are going to be using supplements like energy drinks and pre-workouts, which contain dangerous amounts of caffeine. I would rather we provide education on the safety and use of creatine, which is not dangerous but beneficial. I would like to see more people using creatine given the ergogenic benefits and no reported adverse effects. Creatine monohydrate is a safe, effective, and inexpensive way to support health and physical performance! Please don’t let, “Joe Public” from accounting or “Susie Quinn,” on Instagram tell you any different.
In good health health, and physical performance,
Wendi Irlbeck, MS, RDN, LD CISSN
Wendi Irlbeck, MS, RDN, CISSN is a registered dietitian nutritionist, and performance coach. Wendi utilizes evidence-based science to tailor nutrition programs for athletes to optimize performance, minimize health risks, and enhance recovery from training while focusing on injury prevention. She partners with parents, sports performance staff, and special needs and recreational athletes to offer nutritional guidance and optimal athletic performance and lifestyle plans. Wendi provides virtual services including telehealth but is based in Nashville, TN. Wendi works with clients of all levels internationally.
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Antonio, J., Candow, D.G., Forbes, S.C. et al. Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show?. Journal of the International Society of Sports Nutrition 18, 13 (2021). https://doi.org/10.1186/s12970-021-00412-w
Grindstaff PD, Kreider R, Bishop R, Wilson M, Wood L, Alexander C, et al. Effects of creatine supplementation on repetitive sprint performance and body composition in competitive swimmers. Int J Sport Nutr. (1997) 7:330–46.
Ostojic SM. Creatine supplementation in young soccer players. Int J Sport Nutr Exerc Metab. 2004 Feb;14(1):95-103. doi: 10.1123/ijsnem.14.1.95. PMID: 15129933.
Kreider, R.B., Kalman, D.S., Antonio, J. et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr 14, 18 (2017). https://doi.org/10.1186/s12970-017-0173-z
Jagim AR, Stecker RA, Harty PS, Erickson JL, Kerksick CM. Safety of creatine supplementation in active adolescents and youth: A Brief Review. Front Nutr. 2018;5:115. Published 2018 Nov 28. doi:10.3389/fnut.2018.00115
Ostojic SM. Creatine supplementation in young soccer players. Int J Sport Nutr Exerc Metab. 2004 Feb;14(1):95-103. doi: 10.1123/ijsnem.14.1.95. PMID: 15129933
Antonio J, Ciccone V. The effects of pre versus post workout supplementation of creatine monohydrate on body composition and strength. J Int Soc Sports Nutr. 2013 Aug 6;10:36. doi: 10.1186/1550-2783-10-36. PMID: 23919405; PMCID: PMC3750511.