CHROMIUM
Chromium is an essential trace mineral. Its primary function is to enhance the action of insulin in regulating blood sugar levels. It also has antioxidant properties and modifies brain serotonin neurotransmitter function. The biologically active form is a low molecular weight compound that is called glucose tolerance factor. It contains chromium, niacin (a B vitamin), glutamic acid and the amino acids glycine and cysteine.
Food sources for chromium include eggs, whole grains, brewer’s yeast, beef, chicken, bananas, shellfish, mushrooms and cheese. A typical diet has 25 to 50 micrograms of chromium daily. Only about 1% of ingested chromium is absorbed into the body. Excretion is primarily through the kidneys.
Supplementations with chromium picolinate, chromium polynicotinate, and chromium aspartate all have experimental and clinical evidence of being effective. A chromium deficiency state induced by a deficient diet in lab animals shows high blood sugar, decreased growth rate, shortened life span and cholesterol deposits in large arteries. Similar symptoms have been seen in people being fed intravenously without chromium (if feeding is prolonged). Toxicity with supplementation is unlikely since absorption is poor and amounts needed to cause toxic symptoms are thousands of times higher than recommended doses.
Clinical studies have shown improved control of blood sugar in people with impaired glucose tolerance (pre-diabetes) or diabetes. The chloride form of chromium appears to be ineffective. Higher doses of up to 1000 micrograms produced better results that lower doses of 200 micrograms.
Increased urinary chromium excretion has been associated with chronic cortisone administration or high sugar consumption. Women with gestational diabetes had better control of blood sugar with chromium supplementation. Patients with elevated blood sugar from cortisone had lower levels with chromium. Reactive hypoglycemia (low blood sugar reactions) improved in one study of chromium supplementation. Changes in cholesterol levels during chromium supplementation have shown mixed results. Chromium supplementation as an aid in weight loss has also shown mixed results.
Psychiatric disorders such as depression, atypical depression and dysthymic disorder have been shown to improve with chromium supplementation. The evidence is that chromium is a safe and useful supplement for diabetes, reactive hypoglycemia, and possibly for certain depressive psychiatric disorders.
Daniel Blodgett MD