Eligibility Criteria:
Inclusion Criteria:
* Only accepting participants in the Boston, Massachusetts area
* Age 21 to 75, male or female
* Willingness to eat prescribed diet for 4 weeks prior to infusion date, and 3.5 days after the infusion date
* Willingness to participate in an infusion protocol, which will require them to stay at the Center for Clinical Investigation (CCI) for one night and return for blood draws every day for the next 3 days.
* Body Mass Index (BMI) 25-35 Kg/m2
* HDL\<45 mg/dL for men, \<55 mg/dL for women
Exclusion Criteria:
* Hematocrit \<33
* Low-density Lipoprotein (LDL) cholesterol \>190 mg/dl
* HDL cholesterol \<20 mg/dl, to exclude those with rare genetic HDL deficiency syndromes
* Fasting Triglycerides \>500 mg/dl to exclude those with risk of pancreatitis
* ApoE genotypes, E2E2, E2E4, and E4E4.
* Lipid lowering medications
* Hormone replacement therapy
* Other medicines that affect plasma lipid levels: e.g. beta blockers, certain psychiatric medicines including Alprazolam, Chlordiazepoxide, Clonazepam, Diazepam, Lorazepam, Oxazepam, Prazepam, Aripiprazole, Chlorpromazine, Chlorprothixene, Clozapine, Flupenthixol, Fluphenazine, Haloperidol, Loxapine, Mesoridazine, Methotrimeprazine, Molindone, Olanzapine, Perphenazine, Pimozide, Pipotiazine, Prochlorperazine, Promazine, Promethazine, Quetiapine, Risperidone, Sulpiride, Thioridazine, Thiothixene, Trifluoperazine, Ziprasidone.
* Thyrotrophin-stimulating hormone: \<0.5 or \>5.0
* alanine aminotransferase : 1.5 x uln or 60 IU/L
* Aspartate transaminase: 1.5 x uln or 60 IU/L
* Bilirubin: outside upper limit. (\>1.2 mg/dL)
* Creatinine: outside upper limit (\>1.00 mg/dL)
* Diabetes by history
* Diabetes by fasting or post-challenge glycemia according to ADA guidelines:
* Fasting hyperglycemia (glucose \>126 mg/dl).
* Post-challenge glucose by standard oral glucose tolerance test, \>200 mg/dl
* Will not eat the provided diet and abstain from alcoholic beverages.
* Women who are pregnant