This research is to investigate the nutritional supplement chromium picolinate. A large number of people use chromium picolinate from health food stores to improve the function of the hormone insulin. The investigators are testing how effective this supplement is and are also monitoring its safety. In patients with diabetes, chromium has been shown to increase sensitivity to the hormone insulin. Since obesity can cause insensitivity or resistance to insulin, the investigators are studying obese individuals with documented insulin resistance. The investigators would like to know if chromium is also effective in treating the insulin resistance associated with obesity.

Inclusion Criteria:

1. age > 18 years;
2. a BMI greater or equal to 30; AND
3. an abnormal 2 hour postprandial glucose (greater than 140 mg/dl but less than 200 mg/dl) following 75 grams of a glucose load.

Exclusion Criteria:

1. positive pregnancy test (all women must have a negative pregnancy test before beginning protocol);
2. diagnosis of cancer;
3. acute illness of any sort, however, patients may be enrolled once they are stable;
4. hemoglobin less than 11.0 g/dl or hemodynamically unstable;
5. creatinine greater than or equal to 1.5 mg/dl;
6. liver dysfunction as evidenced by elevations in transaminases 2-fold higher than upper limit of normal;
7. use of certain medications within the past month (e.g., glucocorticoids).
8. untreated hypertension (systolic BP > 150 mmHG, diastolic BP>IOO mmHG);
9. patients with diabetes mellitus;
10. hypogonadism;
11. abnormal thyroid function (serum T4 < 4 or > 12; TSH < 0.35 or > 5.5) (12) any chronic liver or kidney disease; OR
12. polycystic ovarian syndrome.