Chromium is now often taken as a supplement for maintaining normal blood glucose levels and normal macronutrient metabolism.
It helps the function of insulin, a hormone which regulates blood sugar, and is responsible for the metabolism and storage of fat, carbohydrate and protein.
Dr Sarah Brewer says: ‘Interestingly, chromium levels are highest just after birth, then rapidly decrease, especially after the age of 10. Levels then become increasingly lower with age. Chromium may play a role in regulating insulin levels.’
What does chromium do?
Blood sugar (glucose) is a vital source of energy for cells. Insulin is a hormone produced by the pancreas that helps transport glucose from the bloodstream to the cells.
Chromium increases insulin binding to cells by boosting the number of active insulin receptors present, allowing glucose to be absorbed from the bloodstream more efficiently. This may lead to improvements in insulin sensitivity in people with type 2 diabetes.
Type 2 diabetes develops when insulin-producing cells in the pancreas are unable to make enough, or when the insulin that is produced does not work properly (known as insulin resistance). Around 3.5 million people in the UK are estimated to have been diagnosed with diabetes.
According to some studies, chromium can have a significant effect on diabetes, and supplements are increasingly recognised as having a place in the management and treatment of this condition.
One 2016 study found patients with type 2 diabetes who used a combination of chromium, niacin and L-cysteine, experienced a statistically significant decrease in insulin resistance compared to those who took a placebo. They also demonstrated a significant reduction in insulin levels compared to the control group. The study authors concluded that chromium supplements have potential as an adjunct therapy for people with type 2 diabetes.
Polycystic ovary syndrome
Polycystic ovary syndrome (PCOS) is a condition that affects one in 10 women in the UK. The three key symptoms are irregular periods, high levels of male hormones which cause excess facial and body hair, and fluid-filled cysts on the ovaries. The exact cause of PCOS isn’t known but it is thought high levels of insulin in the body may be involved. Women with PCOS are at higher risk of developing type 2 diabetes.
In a 2013 trial, 200mcg daily chromium picolinate supplements were given to women with PCOS who were resistant to the first-line drug treatment clomifene. This significantly reduced their fasting blood sugar levels and improved their insulin sensitivity. The effects were comparable to those of the diabetes drug metformin, and the chromium supplements were better-tolerated.
Getting chromium from your diet
Chromium is found in many different food sources, including egg yolk, red meat, potatoes, cheese, fruit, whole grains, honey, vegetables and spices. However, most foods only provide small amounts (less than 2mcg per serving), and foods that are high in sugars or are processed will contain less chromium. As you get older, you’re even less likely to absorb enough chromium through your diet.
Taking chromium supplements is considered safe for most people, although they can have side effects, most commonly headaches, sleep problems or mood changes. Rare cases of kidney damage, muscle problems and skin reactions have been reported in people who took large doses.
Intakes of 10mg a day or less have been judged unlikely to cause any harm in an adult.
Because it affects blood glucose levels, people with diabetes should only take chromium under supervision of their doctor. Avoid taking if you have epilepsy. Consult your doctor before taking chromium if you are on beta-blockers or corticosteroids.
There is no recommended daily intake set for chromium, but the Expert Group on Vitamins and Minerals said an adequate level of intake would be above 0.025mg for adults. Choose supplements which contain chromium picolinate, the most bio-available form of chromium. A typical dosage is one 200mcg tablet of chromium picolinate a day.