The purpose of this study is to test the relationship between frequency of meals and hepatic fat content and insulin sensitivity. We, the researchers at Rockefeller University, hypothesize that low plasma insulin levels (as achieved by periods of fasting) will prevent insulin resistance and reduce hepatic lipid content. In contrast, frequent, carbohydrate-rich meals will predispose to hepatic steatosis (non-alcoholic) and insulin resistance.

This is a 6 week inpatient study.

The hypothesis will be tested by studying two groups of normal subjects who will receive a defined weight maintenance diet: one group will be given meals twice a day and other group will be given eight meals (snacks) per day. At the beginning of the study period and after 4 weeks following the specified frequency of meals, the study subjects will have their whole body insulin sensitivity and hepatic fat content measured by the euglycemic-hyperinsulinemic clamp and MRI of the liver, respectively.

Inclusion Criteria:

1. Healthy individuals
2. Age between 18-45 years
3. Body mass index (BMI) between 18.5 - 24.9

Exclusion Criteria:

1. Diabetes mellitus
2. Chronic drug treatment for any medical condition like hypertension or hyperlipidemia, hyperthyroidism or taking weight control medications.
3. Inability to give informed consent.
4. Inability to give contact information including permanent residence or provide evidence of stable living environment for the study period.
5. Active weight reduction of more than 7 pounds in the last 3 months.
6. History of bleeding or blood clotting disorders.
7. Pregnancy or breast-feeding in the women.
8. History of anaphylaxis or anaphylactoid-like reaction as a result of food allergies.
9. HIV or hepatitis B and C positive subjects.
10. Subjects with hemoglobin < 8.5 gm/dl.
11. Abnormal liver function test (ALT, AST, alkaline phosphate, LDH, GGT or total bilirubin).
12. Serum creatinine or BUN greater than the upper limit of the normal, serum albumin less than 3.5g/dl, or proteinuria 1+ or greater.
13. History of alcohol intake of more than 40 g/day.
14. Contraindications to magnetic resonance imaging (MRI) including pacemakers, surgical clips, metallic implants, neuromuscular- skeletal stimulators and internal orthopedic screws or rods.