Chromium is a trace mineral found in many foods and sold as a supplement, most often as chromium picolinate. Human trials have found small changes in blood sugar, body weight and some lab markers, but the changes are modest, the studies are often small or short, and several reviewers say they may not matter in practice. No clear deficiency state has been defined in healthy people, so the strongest case for chromium is not that you are likely to be short of it.
Quick facts about chromium
| Item | What the sources report |
|---|---|
| Forms | Chromium picolinate, nicotinate, polynicotinate, chloride and histidinate, plus chromium-enriched yeast. The form in food and supplements is trivalent (+3) chromium, per the NIH Office of Dietary Supplements fact sheet. |
| Doses used in studies | 1.28 to 1,000 mcg a day in blood sugar trials; 200 to 1,000 mcg a day in weight and polycystic ovary syndrome (PCOS) trials |
| Typical study length | 3 weeks to 6 months for blood sugar; 8 to 24 weeks for PCOS; 9 to 24 weeks for weight |
| Main studied uses | Type 2 diabetes and blood sugar, weight and body fat, PCOS, cholesterol and triglycerides, metabolic syndrome, inflammation markers |
| Proposed way it works | It may help insulin act, possibly through a chromium-binding compound called chromodulin; the exact mechanism has not been identified |
What do human studies show about chromium benefits?
No use has strong evidence. The sections below summarize the results by studied use, including where reviews disagree or effects appear small. To judge claims like these, it helps to know how meta-analyses combine studies and how to weigh evidence quality.
Weight and body fat: a very small effect
A 2019 meta-analysis of 21 randomized trials, covering 1,316 adults with overweight or obesity, pooled trials of 9 to 24 weeks using 200 to 1,000 mcg a day, mostly as picolinate. As reported by the NIH fact sheet, people taking chromium lost 0.75 kg more than those on placebo, with a 0.40 kg/m² lower BMI and 0.68% lower body fat. Waist circumference and waist-to-hip ratio did not change. A 2013 Cochrane review called the effect of “debatable clinical relevance” with low-quality evidence. The Harvard Nutrition Source describes the same Cochrane result as about 2 pounds more than placebo and notes the trials were short, small and did not control for diet or exercise. The Merck Manual says there is no overall evidence to support using chromium and no evidence that chromium picolinate improves body composition.
Blood sugar and type 2 diabetes: slight changes, unclear meaning
A 1997 randomized trial of 180 adults with type 2 diabetes gave chromium picolinate or placebo for 4 months. Average HbA1c (a long-term blood sugar measure) was 7.5% on 200 mcg a day, 6.6% on 1,000 mcg a day and 8.5% on placebo, according to the NIH fact sheet. Later results were inconsistent. A 2010 trial of 137 people using 1,000 mcg a day for 24 weeks found no significant effect on insulin sensitivity, fasting glucose or HbA1c overall, though a subset who started with worse insulin resistance and higher glucose did respond.
A 2019 review of eight meta-analyses covering 58 trials found chromium lowered fasting glucose and HbA1c slightly when added to treatment, with unclear clinical significance. A 2016 NIH-authored review in Nutrition Reviews examined 20 randomized trials in type 2 diabetes. Average fasting glucose reached the treatment goal in 5 of 20 studies and HbA1c in 3 of 14. Most trials enrolled people already taking diabetes medicines, only 11 of 20 used the stronger intention-to-treat analysis, and the reviewers saw little reason to recommend chromium for glycemic control. A 2025 meta-analysis of 20 trials in people with overweight or obesity (abstract) found fasting glucose down 1.60 mg/dL and HbA1c down 0.05%, but the confidence intervals for both included zero. Fasting insulin and an insulin resistance score (HOMA-IR) did fall.
The American Diabetes Association concluded in 2010 and 2015 that evidence was insufficient to support routine chromium use for glycemic control. The FDA allows only a qualified claim saying a relationship between chromium picolinate and insulin resistance or type 2 diabetes is “highly uncertain.” The Harvard Nutrition Source adds that benefit looks clearer in people who are deficient and less clear in adequately nourished people.
Polycystic ovary syndrome (PCOS): mixed
Reviews disagree. A meta-analysis of 7 trials with 351 participants (200 to 1,000 mcg a day, 8 to 24 weeks), reported by the NIH fact sheet, found no effect on fasting glucose or total testosterone, but BMI fell 2.37 kg/m², free testosterone fell 0.52 pg/mL and fasting insulin fell 0.33 milli-IU/mL. Another review of 5 trials with 268 women found a small effect of uncertain clinical relevance, and a systematic review concluded chromium did not improve weight loss or metabolic variables.
A newer 2025 meta-analysis of 10 trials with 683 women (abstract) reported lower fasting insulin, triglycerides, total and LDL cholesterol, and more ovulation than placebo. In the comparison with metformin, chromium was more effective for one insulin resistance score and luteinizing hormone. The authors suggested 200 mcg of picolinate may give benefits similar to metformin on some measures, but they also said more trials are needed. That is a pooled-trial comparison with limits, not evidence that chromium can stand in for a prescribed drug. A 2026 meta-analysis of 11 trials with 618 women (abstract) pooled several minerals, including chromium, so it cannot isolate chromium alone. It found lower glucose, insulin and HOMA-IR, with mixed lipid effects.
Inflammation markers: lab changes only
A 2025 meta-analysis of randomized trials in adults (abstract) found chromium lowered C-reactive protein by 0.58 mg/L and TNF-alpha by 1.22 pg/mL. The IL-6 decrease was not significant. The authors said the chromium form, participants’ BMI, sample size and region all predicted the effect. These are blood markers, and a change in a marker does not show that people felt or did better; see surrogate outcomes in trials.
Cholesterol and triglycerides: inconsistent
A trial of 71 people with poorly controlled type 2 diabetes found no effect of 600 mcg a day of picolinate for 4 months on total, HDL or LDL cholesterol or triglycerides. An 8-week trial of 40 women with PCOS using 200 mcg a day found triglycerides fell 19.2 mg/dL versus a rise of 8.3 on placebo, and total cholesterol fell 15.3 versus 0.6. Meta-analyses in diabetes and PCOS showed no significant change in total or LDL cholesterol. Two meta-analyses found HDL up by 1.73 to 4.64 mg/dL and triglycerides down by 11.71 to 26.57 mg/dL. The NIH fact sheet says more research is needed to know if any effect is clinically significant.
Metabolic syndrome: no clear benefit
Only a few trials exist. In 63 adults taking 500 mcg of picolinate twice daily for 16 weeks, chromium raised the acute insulin response to glucose but did not change HbA1c, insulin sensitivity, weight or blood lipids. In 70 adults with metabolic syndrome and impaired glucose tolerance, 300 mcg a day of chromium yeast for 24 weeks changed nothing in glucose, HbA1c, waist, blood pressure or lipids. A separate observational study of 3,648 young adults linked higher toenail chromium to less metabolic syndrome over 23 years, but an observational link cannot show that a supplement would help. The NIH fact sheet concludes that limited research suggests no significant benefit.
What doses and food amounts have been studied?
These are the amounts researchers used and the reference intakes for food. They are not advice on what to take.
| Setting | Amount of chromium |
|---|---|
| Blood sugar trials (20 trials in type 2 diabetes) | 1.28 to 1,000 mcg a day, 3 weeks to 6 months |
| Weight trials (meta-analysis of 21) | 200 to 1,000 mcg a day, 9 to 24 weeks; a Harvard-described meta-analysis used a median of 400 mcg |
| PCOS trials | 200 to 1,000 mcg a day, 8 weeks to 6 months |
| Metabolic syndrome trials | 300 mcg a day (yeast) to 1,000 mcg a day (picolinate), 16 to 24 weeks |
| Multivitamin/mineral products | Typically 35 to 120 mcg |
| Chromium-only products | Commonly 200 to 500 mcg, some up to 1,000 mcg |
| Adequate Intake from food, adults 19 to 50 | 35 mcg for men, 25 mcg for women (30 and 20 mcg after 50), per MedlinePlus |
The Daily Value on labels is 35 mcg. The trials used amounts far above what food supplies, and the NIH fact sheet calls these pharmacologic doses. Doses from diet vary: a small U.S. study found average intakes of about 29 mcg a day for women and 54 mcg for men. Absorption is low, about 0.4% to 2.5% from food.
Which foods contain chromium?
Values vary widely with soil, processing and stainless steel contact, so treat them as a guide.
| Food | Chromium (mcg) |
|---|---|
| Grape juice, 1 cup | 7.5 |
| Ham, 3 oz | 3.6 |
| Brewer’s yeast, 1 tbsp | 3.3 |
| Orange juice, 1 cup | 2.2 |
| Beef, 3 oz | 2.0 |
| Turkey breast, 3 oz | 1.7 |
| Apple with peel, 1 medium | 1.4 |
| Banana, 1 medium | 1.0 |
Most dairy and sugary foods are low. The Merck Manual lists whole grains, carrots, potatoes, broccoli and molasses as good sources, and MedlinePlus lists liver, eggs, oysters and wheat germ.
What are the downsides, side effects and dangers?
The Food and Nutrition Board linked no adverse effects to high chromium intake from food or supplements and set no upper limit, but it said caution may be warranted because data are limited. Specifics by source:
| Concern | What is reported |
|---|---|
| Mild effects in trials | Skin rash, constipation, decreased appetite and flatulence in trials that reported adverse events, but only 11 of 20 diabetes trials did (Nutrition Reviews) |
| Isolated reports | Diarrhea, vertigo, hives, headaches (Harvard); case reports of weight loss, anemia, low platelets, liver dysfunction, kidney failure, muscle breakdown, dermatitis and low blood sugar (NIH) |
| Kidney and liver | Harvard cites case reports of kidney damage at 1,200 to 2,400 mcg daily for four months; the Merck Manual notes rare kidney or liver damage |
| Stomach and iron | Merck says some forms may irritate the stomach or cause ulcers, and supplements interfere with iron absorption |
| Chromosome damage | Merck says some evidence suggests chromium damages chromosomes and may be harmful or cause cancer |
Merck also says studies have shown daily doses up to 1,000 mcg to be safe, and the NIH-authored review above says no major safety problems appeared in the trials. Merck’s overall view is that the small potential benefit may not offset the small risk, and it does not recommend chromium supplements.
What happens if you take it every day?
The trials above ran for at most about 6 months. Chromium accumulates mainly in the liver, spleen, soft tissue and bone and leaves mainly in urine. What happens with years of daily use at supplement doses is not covered by the trials.
Is hexavalent chromium the same thing?
No. Supplements and food contain trivalent chromium. Hexavalent chromium is an industrial by-product, toxic and carcinogenic when inhaled, per Harvard and the Linus Pauling Institute. A 2026 meta-analysis of workplace exposure concerns that form, not supplements.
Medicine interactions
- Insulin and sulfonylureas: chromium may lower blood sugar further and raise the risk of low blood sugar (NIH, Merck). Merck says this is not expected with metformin.
- Levothyroxine: Merck says taking chromium at the same time may reduce how much thyroid medicine is absorbed, so dose adjustment may be needed. Ask your prescriber how to handle this; do not adjust it yourself.
- Other drugs: Harvard lists corticosteroids, proton pump inhibitors, beta-blockers, insulin and anti-inflammatory painkillers (NSAIDs) as potential interactions.
- Absorption: vitamin C and aspirin-type drugs increase chromium absorption; antacids and oxalate reduce it (NIH).
Who should talk to a clinician first?
- Anyone with kidney or liver disease; the Food and Nutrition Board flagged these groups as possibly more susceptible, and Merck says they should not use chromium.
- Anyone with iron deficiency (Merck).
- Anyone with diabetes. Chromium is not a replacement for prescribed treatment, and the American Diabetes Association does not recommend it for glucose control.
- Anyone taking insulin, a sulfonylurea, levothyroxine, a corticosteroid, a proton pump inhibitor, a beta-blocker or an NSAID.
- Anyone combining chromium with other supplements. Tell your clinician or pharmacist everything you take.
What is still unknown?
Is it essential, and what does deficiency look like? The Food and Nutrition Board treated chromium as essential in 2001, and MedlinePlus still describes it that way. But the European Food Safety Authority concluded in 2014 that no convincing evidence shows it is essential, and the NIH fact sheet says no deficiency symptoms have been established in healthy people and no validated test of chromium status exists. Three 1970s and 1980s case reports in patients on long-term intravenous nutrition described high blood sugar, weight loss, nerve problems and confusion that improved with chromium, but later reviewers said those reports did not prove deficiency.
Other open questions. Who might respond (people with more severe insulin resistance are one hypothesis), whether form or dose matters (reviews could not tell, because trials differed too much), what long-term use does, and whether small lab changes matter to health. Trials with defined chromium forms, intention-to-treat analysis and background diet and medicine tracked are still needed. See ingredient evidence versus marketing claims for how to read promotional language around this mineral.
How do you read a label that lists chromium?
- Amount: the Supplement Facts panel lists elemental chromium, not the weight of the whole compound. Chromium picolinate is only 12.4% elemental chromium by weight, so compare the mcg of chromium to the trial doses above.
- Form: picolinate, nicotinate, polynicotinate, chloride, histidinate or yeast. Absorption is similar across forms (about 1.2% for picolinate versus 0.4% for chloride), and no form has been shown to be better.
- % Daily Value: based on 35 mcg, so a product listing several hundred percent supplies far more than food does.
- Yeast products: trials sometimes stated the yeast dose rather than the chromium dose, so look for a stated chromium amount.
- Proprietary blends: if a blend lists one total weight without the chromium amount, you cannot compare it with study doses. Ask the maker for the chromium per serving before you buy.
Before you ask a clinician or buy
- What is the elemental chromium per serving, and in what form?
- Do I take insulin, a sulfonylurea, levothyroxine or other medicines that interact?
- Do I have kidney, liver or iron problems?
- What does my own blood sugar or weight goal need that chromium trials have not shown?
By ClinicalStudyConnect.com Research Desk