Chromium picolinate: uses and safety

What is chromium picolinate?

Chromium picolinate is chromium bound to picolinic acid, made synthetically for use in supplements. Chromium itself is a trace mineral. The form in food and supplements is trivalent chromium, often written chromium(III). Hexavalent chromium, chromium(VI), is a man-made industrial chemical and a different thing altogether.

You need very little. The NHS says around 25 micrograms (µg) a day should be enough for adults, and lists meat, nuts and cereal grains as good sources. The UK's Expert Group on Vitamins and Minerals (EVM) adds processed meats, wholegrain products, pulses and spices. When the EVM reviewed chromium in 2003, the only cases of deficiency it found in people were in patients fed intravenously for long periods. The Food Standards Agency (FSA) says most people can get the chromium they need from a healthy, balanced diet.

According to the EVM, the picolinate form is absorbed better than other forms of chromium(III), though absorption of chromium(III) in general is low, at about 0.5 to 2%.

What does chromium picolinate do?

In Great Britain, chromium can be said to contribute to normal macronutrient metabolism and to the maintenance of normal blood glucose levels. These are the only two authorised claims for chromium on the Great Britain nutrition and health claims register, and they apply to any form of chromium(III), picolinate included:

• Chromium contributes to normal macronutrient metabolism.
• Chromium contributes to the maintenance of normal blood glucose levels.

A product can use them only if it's at least a "source of" chromium. For a supplement that means 15% of the nutrient reference value (NRV) in a daily dose. The NRV for chromium is 40 µg, so 15% is 6 µg.

Both claims describe a role chromium plays in the body. Neither says a supplement lowers blood sugar, and neither says anything about weight or cravings. The register lists claims linking chromium to body weight maintenance and weight control as not authorised because the evidence was insufficient, and it carries no authorised claim about chromium and appetite.

In 2014 the European Food Safety Authority (EFSA) looked at setting a daily requirement for chromium. It concluded that chromium's essential role in metabolism hadn't been substantiated, found no evidence of beneficial effects from chromium intake in healthy people, and set no reference value. The two claims rest on an earlier EFSA assessment from 2010 and remain authorised in Great Britain.

Chromium supplement benefits: what does the research show?

The main systematic review of chromium picolinate and body weight found weak evidence, and Diabetes UK says there's no evidence that chromium can prevent or cause diabetes.

On weight, a 2013 Cochrane review (Tian and colleagues) analysed nine randomised trials of chromium picolinate in 622 overweight or obese adults. The trials used doses from 200 to 1000 µg and lasted up to 24 weeks. Across the doses it found an effect on body weight of debatable clinical relevance, based on low-quality evidence. The authors concluded there was no current, reliable evidence to inform firm decisions about whether chromium picolinate supplements work or are safe. Our guide to appetite suppressants in the UK explains what does have evidence.

On blood sugar and diabetes, Diabetes UK lists chromium among the micronutrients still being researched and says there's no evidence any of them can prevent or cause diabetes. It also says vitamin and mineral supplements have no clear benefits for people with diabetes unless you have a deficiency or your doctor prescribes them, and that supplements can affect the way diabetes medicines work. Chromium isn't a treatment for diabetes, and it's no substitute for anything your GP or diabetes team has prescribed.

Is chromium picolinate safe?

UK and European bodies have concluded that chromium picolinate is unlikely to cause harm at the amounts below, though the UK advice changed along the way.

In 2003 the EVM said there wasn't enough data to set a safe upper level for chromium. It gave a guidance level of 10 mg a day for chromium(III) but excluded chromium picolinate, because lab studies in mammalian cells had shown DNA damage and two case reports had linked picolinate supplements with kidney failure. It called for more research. The FSA then advised anyone who wanted a chromium supplement to use another form until its Committee on Mutagenicity (COM) had looked at the evidence.

The COM asked for further studies and received the results in November 2004. It concluded that the balance of evidence suggested chromium picolinate was not genotoxic. On 13 December 2004 the FSA withdrew its advice, said there was no need to avoid chromium picolinate, and pointed people who take chromium supplements to the 10 mg a day level.

In 2010 EFSA reviewed newer studies, including long-term animal studies. It concluded that chromium picolinate as a source of chromium in food supplements and fortified foods was not of concern provided total chromium doesn't exceed 250 µg a day, the World Health Organization's limit for chromium from supplements. EFSA also noted that at high concentrations in laboratory tests, chromium picolinate might still cause DNA damage.

The NHS now says there isn't enough evidence to know the effects of taking high doses every day, and that 10 mg or less a day from food and supplements is unlikely to cause any harm. The Food Safety Authority of Ireland adopts the 250 µg figure for supplements.

Who should not take chromium picolinate?

The Food Safety Authority of Ireland says people with existing kidney or liver disease may be particularly susceptible to harm from excess chromium and should avoid supplemental chromium. Diabetes UK says supplements can interfere with diabetes medicines. The NHS page on chromium gives no pregnancy-specific advice, so if you're pregnant or breastfeeding, ask your GP, midwife or pharmacist first. Natura's supplements are for adults aged 18 and over.

Chromium tablets: how much do you need?

Most people don't need a chromium tablet, because a varied diet covers the NHS's 25 µg a day. If you take one, check the strength in micrograms and add up everything you take, because multivitamins and blends can contain chromium too. When the EVM reported in 2003, it found multivitamin and mineral supplements on sale with up to 600 µg.

That applies to our own range. Daily Chromium has 25 µg, Daily Multi has 200 µg, and Daily Hormone (in the Hers Hormone Pack) has 100 µg. Daily Multi with Daily Chromium comes to 225 µg a day. Daily Multi with Daily Hormone comes to 300 µg, and all three together to 325 µg. Both of those totals are above the 250 µg EFSA used for supplements, though far below the NHS figure of 10 mg. Daily Multi also comes in packs such as the Core Pack, so check packs as well as single bottles. If you take more than one product with chromium in it, check the total with a pharmacist. Our guide to which supplements you can take together covers spacing and overlaps in more detail.

Glucomannan and chromium: what are the benefits?

No claim is authorised for glucomannan and chromium as a pair. Some products combine them, but each has its own claim and the two say different things.

Glucomannan is a fibre from the konjac plant. Its claim is "Glucomannan in the context of an energy restricted diet contributes to weight loss". It applies only at 3 g a day, taken as three 1 g doses, each with 1 to 2 glasses of water before meals. The claim must carry a choking warning for people with swallowing difficulties, so take it with plenty of water and ask your GP or pharmacist first if swallowing is hard for you. Chromium's claims say nothing about weight, so a combination product can't say the chromium adds to the glucomannan claim.

If you're comparing products, check that each dose gives 1 g of glucomannan. Our glucomannan guide covers the dose, the research and the safety rules in full.

Where Natura fits

Daily Chromium, in the Natura cabinet (coming soon), is one capsule with 25 µg of chromium as picolinate, which is 62.5% of the NRV. It also comes in the Trace Pack. That meets the source-of condition for both authorised claims: chromium contributes to normal macronutrient metabolism and to the maintenance of normal blood glucose levels. It carries no other claims.