Slide 1:Chromium Picolinate:A Critical Analysis of the Ergogenic Claims By
Jennifer MacWhorter
for
HE 426 Sports & Exercise Nutrition
Slide 2:Classification & Usage Cr(pic)3 is the combination of the essential trace mineral chromium and picolinic acid.
Picolinic acid increases absorption rate from .5-2% to 2-5%.
Vincent, John B. (2003). The Potential Value and Toxicity of Chromium Picolinate as a Nutritional Supplement, Weight Loss Agent and Muscle Development Agent {Electronic Version}. Sports Med, 33 (3), 213-230
Slide 3:Classification & Usage Daily adequate intake for chromium is 35mcg (males) and 25mcg (females).
Naturally found in brewers yeast, whole grains, nuts, cheese, beer, and mushrooms
The more processed food is, the less chromium it will contain.
Williams, Melvin H. (2005). Nutrition for Health, Fitness, & Sport. Boston: McGraw-Hill
Slide 4:Classification & Usage Cr(pic)3 works with insulin to metabolize carbohydrates, fats, and proteins. Supplementation can help increase insulin production and improve body composition. Low levels of insulin can lead to insulin resistance, with an increased risk for diabetes, cardiovascular complications and obesity.
Slide 5:Classification & Usage Cr(pic)3 from GNC costs between $7.99-$14.99 for 90 capsules of 500 mcg.
Recommended dose of up to 1000 mcg/day
1 years worth would cost ~$120
10 million Americans consume more than $150 million in chromium supplements each year.
Slide 6:Performance Factor Claims
Appetite suppressant
Leads to weight and fat loss
Increases efficiency of insulin
Promotes insulin transfer of glucose from bloodstream to cells, creating more energy
Extra energy may increase the production of serotonin, which will subsequently reduce appetite
Allen, Amanda (2003). Chromium Picolinate and Weight Loss. Retrieved Feburary 11, 2006, from www.vanderbilt.edu/AnS/psychology/health_psychology/chromiumpicolinate.htm
Slide 7:Performance factor Targeted populations
Elderly
Less chromium is absorbed as humans age
Athletes
When stress is placed upon body more chromium is excreted. Endurance/strength type exercise may lead to lower levels in the body.
Slide 8:Effectiveness Cr(pic)3 claims to improve insulin sensitivity
Useful only if diet is lacking in chromium
Diets lacking in chromium may cause Type 2 diabetes
The addition of chromium may help reverse the onset of Type 2 diabetes
If there is no shortage of chromium, will supplementation be useful???
Slide 9:Effectiveness 40 people with impaired glucose tolerance took either a placebo or 400 mcgs twice daily of Cr(pic)3. Effects were measured on glucose tolerance, insulin resistance and lipids. No benefits were gained from the supplementation.
Shows that the addition of Cr(pic)3 does not improve insulin sensitivity unless the person is already deficient in chromium.
Gunton, Jenny E., Cheung, N. Wah. Hitchman, R., Hamms,G. O’Sullivan, C., Foster-Powell, K., & McElduff, A. (2005). Chromium Supplementation Does Not Improve Glucose Tolerance, Insulin Sensitivity, or Lipid Profile {Electronic Version}. Diabetes Care, 28, 712-713.
Slide 10: Effectiveness Cr(pic)3 claims to decrease fat mass and increase lean body mass
This would depend on how insulin is affected by chromium supplementation.
Slide 11:Effectiveness Wrestlers were given 200 mcg of Cr(pic)3 daily for 14 weeks.
Double blind, placebo-controlled study
Measurements were taken from underwater weighing, skin folds, and body circumferences
No effect was found on body mass, lean body mass, percentage body fat, fat mass, or strength
Vincent, John B. (2003). The Potential Value and Toxicity of Chromium Picolinate as a Nutritional Supplement, Weight Loss Agent and Muscle Development Agent {Electronic Version}. Sports Med, 33 (3), 213-230
Slide 12:Effectiveness 40 day study involving 18-21 year old males half of which were receiving 200 mcg of Cr(pic)3 daily.
Participants engaged in two, 40 minute exercise periods a week
Body composition measured by the thickness of skin folds and bicep and calf circumferences.
Slide 13:Effectiveness Participants receiving supplement
average 2.2 kg body mass
average 1.6 lean body mass
No change in body fat
Participants not receiving supplement
average 1.25 kg body mass
average .04 kg lean body mass
average 1.1% body fat
Slide 14:Effectiveness Any studies done that promote the use of Cr(pic)3 as a fat burner and muscle builder were unable to produce similar results in repeated, more controlled studies.
Measurements would be taken in ways that inadequately measure the affects (skin fold and circumference) vs. more accurate measurements (underwater weighing, dual x-ray absorptiometry, magnetic resonance).
Slide 15:Safety Generally thought to be safe in recommended doses.
Chinese hamster ovary (CHO) cells were found to develop cleavage of chromosomes.
Used unpurified Cr(pic)3
No conclusive studies done on humans
Slide 16:Safety Long term studies on safe levels of Cr(pic)3 still need to be done
People supplementing usually take amounts well over the RDA. The effects of taking such an increased amount have not been studied effectively enough to know how it affects the human body.
Slide 17:Safety Reported effects
Anemia
Renal failure
Liver dysfunction
Hypoglycemia
Acute, short-lasting cognitive, perceptual and motor changes
Slide 18:Safety Overdose amount not yet known
Over a thousand times the adequate daily intake will cause no immediate danger
Levels are measured by hair or blood samples, no quick tests are available to assess levels
Slide 19:Ethical & Legal Issues Cr(pic)3 is a legal supplement in the United States and there are no negative ethical issues with regard to safety.
Slide 20:Recommendation Recommend use only if showing early signs of Type 2 diabetes.
First try to naturally increase levels by changing diet.
Not recommended as a weight loss aid or to increase lean body mass
No conclusive studies done to support use