Chromium and Insulin Resistance

Sponsor

University of California, San Francisco (Other)

Overall Status

Completed

CT.gov ID

NCT00846248

Collaborator

(none)

Enrollment

Location

Arms

65.9

Duration (Months)

1.1

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Condition or Disease	Intervention/Treatment	Phase
Insulin Resistance	Dietary Supplement: Chromium Dietary Supplement: placebo	N/A

Detailed Description

Chromium is an essential nutrient for the maintenance of normal glucose tolerance and its deficiency causes insulin resistance. Chromium administration has also been shown in several studies to lower glucose and insulin levels in patients with type 2 diabetes. Moreover, studies in humans, animals and cell culture indicate that chromium enhances insulin signaling. While these studies suggest that chromium administration increases insulin sensitivity, it has not been directly demonstrated that chromium has an effect in well defined insulin resistant subjects independent of hyperglycemia. Accordingly, we propose to perform a placebo-controlled study of chromium picolinate administration in a cohort of non-obese, non-diabetic, insulin resistant subjects. The insulin sensitivity of 80 subjects will be measured by a euglycemic insulin clamp. Approximately 40 insulin resistant subjects will be randomized to 16 weeks of therapy with either 500 ug twice a day of chromium picolinate or placebo. To quantitate the chromium-induced improvements, euglycemic hyperinsulinemic clamps to evaluate insulin sensitivity, OGTT using deuterated glucose to evaluate glycolytic glucose disposal, and muscle biopsies to evaluate insulin signaling pathways, will be performed before and after treatment. We believe these studies will (1) confirm the beneficial effect of chromium on insulin sensitivity; (2) further our understanding of the molecular mechanisms of chromium action; and (3) because these insulin resistant subjects are at risk for the development of type 2 diabetes, the Metabolic Syndrome, and coronary artery disease (CAD), a demonstration of the beneficial effects of chromium on insulin action could ultimately have important public health consequences.

Study Design

Study Type:

Interventional

Actual Enrollment :

75 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

Double (Participant, Investigator)

Primary Purpose:

Prevention

Official Title:

Chromium and Insulin Resistance

Study Start Date :

Jan 1, 2006

Actual Primary Completion Date :

Jul 1, 2009

Actual Study Completion Date :

Jul 1, 2011

Arms and Interventions

Arm	Intervention/Treatment
Active Comparator: 1 Chromium picolinate	Dietary Supplement: Chromium We will enroll non-obese, non-diabetic subjects with insulin resistance in a 16 week treatment program with 500 μg of chromium picolinate twice daily. Insulin action will be determined by insulin clamp and OGTT using deuterated glucose both before and after treatment. Subjects will be compared to a placebo-treated group.
Placebo Comparator: 2 2 sugar pills taken twice daily	Dietary Supplement: Chromium We will enroll non-obese, non-diabetic subjects with insulin resistance in a 16 week treatment program with 500 μg of chromium picolinate twice daily. Insulin action will be determined by insulin clamp and OGTT using deuterated glucose both before and after treatment. Subjects will be compared to a placebo-treated group. Dietary Supplement: placebo We will enroll non-obese, non-diabetic subjects with insulin resistance in a 16 week treatment program with 500 μg of chromium picolinate twice daily. Insulin action will be determined by insulin clamp and OGTT using deuterated glucose both before and after treatment. Subjects will be compared to a placebo-treated group.

Arm

Intervention/Treatment

Active Comparator: 1

Chromium picolinate

Dietary Supplement: Chromium

We will enroll non-obese, non-diabetic subjects with insulin resistance in a 16 week treatment program with 500 μg of chromium picolinate twice daily. Insulin action will be determined by insulin clamp and OGTT using deuterated glucose both before and after treatment. Subjects will be compared to a placebo-treated group.

Placebo Comparator: 2

2 sugar pills taken twice daily

Dietary Supplement: Chromium

Dietary Supplement: placebo

Outcome Measures

Primary Outcome Measures

insulin resistance [0 months and 4 months]

Eligibility Criteria

Criteria

Ages Eligible for Study:

20 Years to 50 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

Not exercising regularly, healthy, non-diabetic.

Exclusion Criteria:

Diabetes, heart disease, hepatitis, HIV, impaired glucose tolerance, abnormal liver enzymes, abnormal TSH levels, other abnormal lab values.

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	UCSF	San Francisco	California	United States	94143

Sponsors and Collaborators

University of California, San Francisco

Investigators

Principal Investigator: Umesh Masharani, MD, University of California, San Francisco
Principal Investigator: Martha Nolte, MD, University of California, San Francisco