Iron Supplements Reviewed by

Iron Supplements Review

Trying to find the best iron supplement? See which iron supplements passed's independent tests. Plus, learn about taking iron to treat iron deficiency anemia and unexplained fatigue, how to avoid stomach upset when taking iron and more.

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4.Angiotensin-Converting Enzyme Inhibitors (ACE Inhibitors)
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... More Results Answers to Questions Found:
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1.What are the signs of iron deficiency anemia?
2.What is the best form of iron supplement?
3.Why is iron not in many multivitamins? How can I find one that does contain iron?
4.Why does dark chocolate have iron in it? Is it, or cocoa, a good dietary source of iron?
5.Which supplements are important after bariatric surgery (i.e., weight loss or stomach-reducing surgery)? Are there any I should avoid?
6.Is it true that calcium interferes with iron absorption? Is it a problem to take a multivitamin containing both minerals?
7.Are supplements with amino acid chelated minerals better than those with other forms of minerals?
8.Which vitamins and minerals should be taken together or separately?
9.Do any supplements help for restless legs syndrome?
10.How does regular black pepper compare with black pepper extract used in supplements? Will sprinkling it on food with turmeric help increase the bioavailability of curcumin compounds from turmeric?  (in Comments)
11.Is it true that taking turmeric/curcumin with food can reduce iron absorption from food?
12.Which supplements can cause constipation?
13.I developed a rash after taking an iron supplement and then realized the supplement contained soy, to which I am allergic. Can your reports help me avoid soy and other allergens in supplements?
14.I'm interested in using Himalayan salt. What are the health benefits with it and other specialty salts? Are there contaminants in these salts?
15.Can vitamin supplements strengthen brittle nails?
16.How likely are Americans to be deficient in vitamins or minerals?
17.Which supplements should be taken with food?
18.Can prenatal vitamins have too much folic acid? Mine has 800 mcg, but isn't that more than what's recommended? Is this dangerous to me or my baby?
19.Are there any supplements I should avoid when taking an antibiotic? Are there any that may be helpful?
20.Does heat kill coronavirus (COVID-19)? Can it disinfect face masks and packages?  (in Comments)
21.How do the Beyond Burger, the Impossible Burger, and a beef burger compare in terms of vitamins and minerals, and which is best?
22.I take a number of supplements and I think they are making my acid reflux worse. Which supplements could be causing my stomach irritation, and what can I do about it?
23.I've heard that soaking dried beans for 24 hours reduces the phytate level, allowing for greater access to nutrients. Is this true?
24.Is it better to get vitamins from foods or supplements, and are natural vitamins better than synthetic vitamins?
25.Which supplements help to improve energy and decrease fatigue?
26.When is the best time of day to take a multivitamin?
27.Why aren't there children's multivitamins specifically for girls vs. boys?
28.I asked the distributor of my cacao powder how it checks for metals. They say they do "foreign material detection" to capture "metal fragments." Is this adequate for checking cacao and cocoa for heavy metals, like cadmium, which you've found in other products?  (in Comments)
29.What is lactoferrin and will it really strengthen my immune system?
30.Are there drug interactions with curcumin or turmeric?
31.Can lysine, vitamin B-12, or other vitamins or minerals help prevent or reduce canker sores?
32.Can vitamins or other supplements cause a change in the ability to taste, or even a loss of taste?
33.Do any supplements really help with brain function, like memory and cognition?
34.Help! How do I know how much magnesium I am actually getting from my supplement? The label says it contains 500 mg of magnesium "as magnesium citrate" -- but how much of that is magnesium and how much is citrate?
35.I have milk allergy and can't eat dairy. What's the best way for me to get calcium?  (in Comments)
36.Do any supplements help reduce the symptoms of premenstrual syndrome (PMS)?
37.Do any supplements help relieve stress?
38.Are enteric coated supplements better than non-enteric coated ones?
39.Do any supplements help for hair loss?
40.Do Sugar Bear Hair Vitamins make hair shine, nails stronger, and help both to grow? They taste good but are super expensive.
41.Is the theobromine in chocolate and cocoa good or bad for me?
42.I take levothyroxine (Synthroid), a thyroid hormone to treat hypothyroidism. Are there supplements I should avoid, or be taking, due to this drug?
43.I thought the B vitamins were all water soluble and did not build up in the body, so you would not build up toxic levels. Am I wrong?  (in Comments)
44.How can I make a mask that is as good as a surgical mask or an N-95 mask?  (in Comments)
45.I'm trying to pick a good multivitamin for my children and husband, and for myself. Any suggestions based on your research?  (in Comments)
46.How much should I expect to pay for supplements? Are higher-priced supplements any better than low-priced brands?
47.I'm thinking of changing my multivitamin, but the one I'm considering doesn't contain molybdenum. Most others have it. How important is molybdenum?
48.I've heard that having low B-12 or B-6 can cause depression. Is that true?  (in Comments)
49.Can taking CoQ10 affect my thyroid levels or interact with my thyroid medication?
50.What are the side effects of curcumin and turmeric?
51.Is sublingual vitamin B-12 really better than the pill form?  (in Comments)
52.Is there a multivitamin that contains only the recommended daily vitamins and minerals? Most that I have looked at contain more.
53.Is there cause for concern with "gummy vitamins?" There are many different gummies out there. Are some better than others?
54.Which supplements can help treat constipation?
55.How can I find supplements that are gluten-free on
56.Do vitamin patches, such as for B12 or multivitamins, really work? How about those from PatchMD?
57.Does taking a laxative interfere with the absorption of vitamins or minerals?
58.Do any supplements reduce side of effects of chemotherapy?
59.Does Restore (Bionic Sciences LLC) really improve gut health? What is in Restore?

Clinical Updates Found:
2020 Precaution When Taking Iron (07/14/2020)
Precaution When Taking Iron
Supplementing with iron can cause constipation and even bowel obstruction. Find how to reduce these risks when taking iron in the ConsumerTips section of the Iron Supplements Review. Also see our Top Picks for iron.
2019 Be Careful With Iron (11/16/2019)
Be Careful With Iron
Iron supplements can be hard on the stomach, but be aware that very high doses may actually cause erosions and ulcers. Certain formulations are less likely to cause this problem. For details, see the Concerns and Cautions section of the Iron Supplements Review. Also see our Top Picks among iron supplements.
 Curcumin Caution: May Lower Iron (03/27/2019)
Curcumin Caution: May Lower Iron
If you’re low in iron, be careful with high doses of curcumin (turmeric extract). See the Concerns and Cautions section of the Curcumin and Turmeric Review. Also see our Top Picks among products.
2018 Drug Interactions With Iron (12/05/2018)
Drug Interactions With Iron
Iron should not be taken at the same time as any of several prescription medications, due to potential interactions. A recent study adds to the list of medications of concern. For details, see the Concerns and Cautions section of the Iron Supplements Review.
 Iron and Stroke (10/29/2018)
Iron and Stroke
Having too much iron in the body is associated with an increased risk of a variety of conditions and, according to a recent study, stroke is among these. For details, see the Concerns and Cautions section of the Iron Supplements Review. (Also see our Top Picks for iron when you need to supplement.)
 Iron Deficiency Cause (10/16/2018)
Iron Deficiency Cause
Regular use of certain popular medicines was associated with a large increase in the risk of iron deficiency, according to a new study. Get the details in the ConsumerTips section of the Iron Supplements Review. (Also see our Top Picks among iron supplements.)
2017 Tea & Iron Absorption (12/16/2017)
Tea & Iron Absorption
A surprising number of foods and beverages, including tea, can interfere with the absorption of iron. When you drink your tea can make a big difference, according to a new study. Get the details in the Iron Supplements Review >>
 Iron for Restless Legs (08/02/2017)
Iron for Restless Legs
Iron supplementation may help to reduce the severity of restless legs syndrome (RLS) symptoms in people who have deficient or low levels of iron, according to guidelines from the American Academy of Neurology. For details, including dosage, see the "What It Does" section of the Iron Supplements Review, which also includes our tests and quality comparisons of products.
 Best Iron? (06/14/2017)
Best Iron?
Contrary to expectations, a study which compared the effectiveness of two forms of iron in treating anemia in young children found ferrous sulfate to be more effective than a newer form of iron. For details about this, the different forms of iron, how to take iron, and our tests and comparisons of brands of iron supplements, see the Iron Supplements Review >>
 What Iron Supplements Can and Cannot Do (05/18/2017)
What Iron Supplements Can and Cannot Do
Iron supplements can reduce fatigue in younger women and even improve learning in adolescent girls. If you give blood, taking iron reduces your time to recover by more than one month. However, a recent study found little benefit in giving iron to heart failure patients low in iron. Researchers have an idea why. For details about the uses of iron, see the "What It Does" section of the Iron Supplements Review, which includes our tests and comparisons of popular iron supplements.
2016 Don't Take Green Tea With Iron? (03/16/2016)
Don't Take Green Tea With Iron?
A study shows that iron can bind to a key flavanol (EGCG) in green tea, causing it to lose its anti-oxidant activity. Should you avoid iron-containing foods when using green tea? Find out in the "What to Consider When Using" section of the Green Tea Supplements and Teas Review >>
2015 Iron After Blood Donation (02/11/2015)
Iron After Blood Donation
A new study showed that iron supplementation speeds the recovery of hemoglobin levels by several weeks after blood donation and suggests that the current time between donations may be too short. For details, as well as our tests of iron supplements, see the Iron Supplements Review >> 
2013 More Iron, Less PMS? (03/31/2013)
More Iron, Less PMS?
A new study showed that women getting more iron had a significantly lower risk of suffering PMS (premenstrual syndrome) -- but not just any type of iron. Get the details, as well as our ratings of iron supplements, in the updated Iron Supplements Review »
2012 Feeling fatigued? Iron may help (07/15/2012)
Feeling fatigued? Iron may help
It's well known that fatigue can result from iron-deficiency anemia, but new research shows that some women who are not anemic can also benefit from iron. Women ages 18 to 53 with unexplained fatigue given iron experienced a nearly 50% reduction in fatigue in a recently published study. Get details about the treatment (including the dosage, duration, and type of iron supplement used) in the update to the Iron Supplements Review, which includes our tests of iron supplements similar to that used in this study. More >>
2011 Women-Vitamin Study - Key Points (10/12/2011)
Women-Vitamin Study - Key Points
You may have heard this week about a new study which found a higher risk of death among women who used certain supplements. It’s a complicated study, but we've summarized some key findings. Bear in mind that only white women ages 55 to 69 were enrolled in the study and they were followed for 22 years.

Those taking calcium supplements had a 3.8% reduced risk of death. The calcium benefit ended, however, when taking more than 900 mg per day from supplements. It's worth noting that experts suggest many older women who take calcium supplements may not need to -- see the Calcium Supplement Review for more.

The mineral most strongly associated with an increased risk of death was iron, which showed a risk increase of 3.9% -- and the risk increased as the dose increased, particularly over 50 mg per day. However, the study grouped dosages of under 50 mg together, making it hard to determine the risk of low dosages of iron, such as those in many multivitamins. However, there is very little reason why a postmenopausal woman should be taking iron -- see the Iron Supplement Review for more.

Although not as statistically meaningful, other supplements were associated with the following increases in the risk of death during the study: multivitamins (2.4%), vitamin B6 (4.1%), folic acid (5.9%), magnesium (3.6%), zinc (3.0%), and copper (18.0%). An abstract of the study is online.

The bottom line: Don't take a supplement you don't need. If you want to know how much of each vitamin and mineral you need from your total diet and how much is too much, see our chart at

Recent Recalls and Warnings Found:
1.Iron Supplements Recalled Due to Undeclared Allergen (07/28/2020)
2.Company Failed to Report Adverse Events Associated With Its Nutrition Shakes (02/26/2020)
3.DMHA and Phenibut Are Not Permitted in Dietary Supplements, Warns FDA (04/16/2019)
4.Maker of Vitamin B12 and Multimineral Supplements Warned by FDA (07/18/2018)
5.FDA Warns Seller of Echinacea, Iron, Aloe Supplements & More for Manufacturing Violations (04/17/2018)
6.FDA Warns Seller of Arthritis, Blood Pressure, Diabetes Supplements For Making Drug Claims (10/18/2017)
7.FDA Warns Consumers Not to Use Certain Liquid Multis, Vitamin D, and Other Supplements Due to Potential Bacterial Contamination (08/18/2017)

Archived Recalls and Warnings Found:
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1.Liquid Multis, Vitamin D & More Recalled Due to Potential Bacterial Contamination (08/09/2016)
2.23,000 ER Visits Linked to Supplements: Palpitations, Swallowing Problems, Allergies Common (10/17/2015)
3.FDA Warns Maker of Fruit Energy Drinks for Drug Claims (06/11/2015)
4.FDA Targets Weight Loss and Workout Supplements Listing Synthetic Stimulant DMBA (04/29/2015)
5.Seller of Vitamin C, Iron and Detox Supplements Warned for Violations, Drug Claims (10/30/2014)
6.Maker of Joint and Weight Products Warned for Hidden Drugs, Manufacturing Violations (09/23/2014)
7.Seller of Aloe, Thyroid and Other Supplements Warned for Manufacturing Violations and Drug Claims (04/16/2014)
8.Seller of Iron, Prostate, Valerian and Other Supplements Warned For Multiple Violations and Drug Claims (02/13/2014)
9.Immune Supplement Recalled Due To Undeclared Milk (08/27/2013)
10.Maker of Algae Products Warned For Drug Claims, Manufacturing Violations (08/01/2013)
11.Maker of Probiotic, Iron and Folic Acid Supplements Warned For Manufacturing Violations (05/03/2013)
12.Recall: Contaminated Iron Supplement (04/19/2013)
13.Manufacturer of Joint, Weight Loss, Muscle Supplements and More Warned for Adulteration, Misbranding and Drug Claims (03/01/2013)
14.Manufacturer of Heart, Multivitamin, Cranberry, and Longevity Supplements Warned For Adulteration and Drug Claims (02/13/2013)
15.Recall: Iron Supplement Containing Motion Sickness Drug (01/18/2013)
16.Men’s Sexual Enhancement Supplement Containing Prescription Drug Recalled (09/18/2012)
17.Makers of Mineral Water Containing Lithium Warned (08/09/2012)
18.FDA Warns XYMOGEN of Manufacturing and Labeling Violations Regarding Multiple Products (01/02/2012)
19.22 Brands of Whey Protein Recalled Due to Salmonella Concern (03/14/2011)
20.Many Brands of Nutrition Bars Recalled Due to Potential Salmonella Contamination (01/24/2009)
21.U.S. Marshalls Seize Supplements Promoted as Drugs (09/12/2006)
22.Recall of Multivitamins with Iron Lacking Child-Resistant Caps (07/13/2005)
23.Recall Update for Portagen Iron Fortified Nutrition Powder (05/24/2002)
24.Recall of Multivitamin Due to Unsafe Bottling For Children (03/12/2002)

News Releases Found:
2020 Best and Worst Multivitamins Revealed by ConsumerLab -- Problems Found With 44% of Multis Tested (04/28/2020)
2018 Reveals Its Top Picks for Best Iron Supplements (01/04/2018)
2017 Gummies Are Most Likely to Fail Testing in Review of Multivitamins -- Best and Worst Multivitamins Identified by ConsumerLab Testing (11/01/2017)
2016 Problems Found with 32% of Multivitamin/Multimineral Supplements -- Identifies Good Choices for Men, Women, and Children (01/12/2016)
2015's Tests of Digestive Enzyme Supplements Reveal What Labels Don't (05/05/2015)
2014 Round-up of Recent Product Tests by -- Results for B Vitamin Supplements & Energy Drinks, Garlic, NAC (N-acetyl cysteine), Iron and Omega-7 Fatty Acids (12/09/2014) Finds Popular Cocoa Powders Contaminated; High Concentrations of Cadmium Raise Concern (08/05/2014)
2013 Use of CoQ10, Digestive Enzymes, Probiotics and B Vitamins on the Rise According to Survey (01/31/2013)
2012 Fish oil and multivitamins most popular supplements in survey -- Internet most popular place to shop (02/05/2012)
2011 puts multivitamins to the test (06/16/2011) finds 100-fold variation in cost of iron supplements (03/30/2011)
 Vitamin D use increased 52% in past two years according to survey of supplement users -- Fish oil continued to surpass multivitamins as most popular supplement and Internet was most common place to buy supplements (01/31/2011)
2010 finds quality of most CLA supplements for slimming to be high; One brand mislabeled -- Report is first published in series on supplements for weight loss and slimming (01/20/2010)
2008 Some iron supplements short on iron or contaminated according to (05/05/2008)
 As problems surface, and the people's pharmacy ask FDA to disclose differences between generic and original drugs (03/17/2008) finds most vitamin C supplements pass quality tests but one short on ingredient and some exceed tolerable levels (03/07/2008)
 Consumers warned of lead in some turmeric supplements — Highest lead level ever reported by; Lack of active compound also a problem (02/06/2008) finds most potassium supplements meet quality standards, but one with only 18% of ingredient — Results for 12 potassium supplements in new review (01/08/2008)
2006 Tests of "muscle" supplements finds some "weak" products but most contain expected creatine, HMB, or amino acids — Review of muscular enhancement supplements published by (11/13/2006)
2005 reports on vitamin C supplements — Test Results for 29 Products Reported Along with Information on Use (03/14/2005)
2004 reports on iron supplements — Wide variety of products pass testing; Consumers advised on proper dose, type of iron to avoid problems (07/26/2004) finds several herbal sleep supplements fail tests for quality — Results for 13 valerian products released today (07/07/2004) warns of deceptive campaign by manufacturer of children's vitamin (05/28/2004)
 Consumers warned of pitfalls with some multivitamins and vitamin waters — Testing by uncovers problems with many brands (05/21/2004)
 New report on St. John's wort highlights benefits and risks of herbal product for depression (04/27/2004)
2002 finds lead contamination remains a problem for certain mineral supplements — Lead found in iron, magnesium and, most recently, potassium pills (07/16/2002)
 Pharmavite dietary supplements receive approval — Vitamin E, SAM-e, St. John's Wort, Ginkgo and others merit approved quality products ranking (07/10/2002)
 Athletic Banned Substances Screening and Certification Program announced by — Tester of supplements to screen for substances banned in Olympics (02/08/2002) finds most B vitamin supplements contain what they claim, but often exceed safe levels — Consumers cautioned to be aware of side effects with high dose products (01/08/2002)
2001 finds fish oil supplements free of mercury, but 30% lacking in key ingredient — Test results of omega-3 fatty acid (EPA and DHA) products released today (11/20/2001)
 Sixty percent of nutrition bars fail to meet claims in tests — "Low Carb" bars often loaded with carbohydrates; excess sodium and saturated fat also found (10/30/2001)
 Most iron supplements pass testing — Lead contamination and insufficient iron found in some (10/03/2001)
 Problems and ambiguity among alternative estrogen products reported by — Results of soy and red clover isoflavone product testing released online today (08/15/2001)
 Many herbal sleep products lack key claimed ingredient — Results of's testing of valerian products released on web today (07/09/2001) reports test results of arthritis supplement — MSM; Quality found higher than for most supplements, but room for improvement remains (06/04/2001)
 Some supplements for arthritis may exceed newly released safe intake levels for manganese (01/29/2001)


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