Chromium is an essential trace mineral that is found in some foods, but is also taken by some people as a supplement.
Foods that are good sources of chromium include liver, kidney, yeast products, wholegrain cereal, nuts and legumes. Most people get enough chromium from food.
Chromium is involved in making glucose available for energy, which is why it has been studied to see if it would be helpful in managing diabetes. However, Diabetes UK says there is no clinical evidence yet to support chromium for people with diabetes.
For a supplement to be sold making claims about being beneficial to aspects of a person's health, claims have to be approved by the European food regulator EFSA.
It has approved a health claim that chromium contributes to the maintenance of normal blood glucose levels.
Health claims that chromium helps with body weight management or reducing fatigue or tiredness have not been approved.
Some studies have also found that chromium may help with polycystic ovary syndrome (PCOS), which is linked to insulin resistance.
In a pilot study published in the US journal Fertility and Sterility, researchers at the State University of New York, analysed the effects of nutritional supplementation with chromium on six women with PCOS. Results showed that daily supplements of 1,000 mcg of chromium significantly enhanced insulin sensitivity. However, this was a small trial and larger controlled trials are needed to confirm efficacy.
Chromium supplements have also been studied for their effects on cholesterol, heart disease risk, psychological disorders, Parkinson’s disease and other conditions. However, the study results have been contradictory or unclear.
Some people use chromium supplements to build muscle or trigger weight loss. Again, results have been inconclusive and more research is needed.
For labelling purposes, the European Union’s Recommended Daily Allowance (EU RDA) for chromium has been set at 40mcg per day for adults.
Many people get more chromium than that. However, no one knows exactly how much more is safe. The UK Expert Group on Vitamins and Minerals report on safe upper limits suggests that intakes of chromium of up to 10mg (10,000mcg) per person per day would be expected to be without adverse health effects. Excessive doses of chromium may actually worsen insulin sensitivity.
Chromium supplement information
Chromium - specifically trivalent chromium - usually comes in capsules and tablets. It’s also sold in many different formulas with different names. The most commonly used is chromium picolinate. Others include chromium chloride and chromium nicotinate.
Another form of chromium not found in foods or supplements - called hexavalent chromium - is used in some industries. It is highly toxic.
- Side effects. Chromium seems to have few side effects. There have been some reports of chromium causing occasional irregular heartbeats, sleep disturbances and allergic reactions. Chromium may increase the risk of kidney or liver damage. If you have kidney or liver disease, do not take chromium without talking to your GP first.
- Interactions. Since chromium may affect blood sugar levels, it is crucial that anyone taking diabetes medications - like insulin - only use chromium under medical supervision.
- Chromium may also interact with medicines like antacids, acid reflux drugs, corticosteroids, beta-blockers, insulin and NSAID painkillers. These interactions may cause the chromium to be poorly absorbed or amplify the effect of the medication being taken.
- Risks. Pregnant and breastfeeding women should not take chromium supplements. For children, consult your child’s GP. There is a theoretical risk that it could increase the risk of cancer, so don’t use chromium in high doses without talking to your doctor first.