Diets With a Spectrum of Fat Intake for Preventing Obesity: A Randomized Controlled-feeding Trial

Inclusion criteria: * Students in Zhejiang University or working stuff in the Chinese PLA General Hospital * 18 ≤ age ≤ 35 * Body Mass Index \< 28\* * Are willing to eat all of the study foods even when full * Are willing to eat only foods provided * Are willing to avoid strenuous activity during the 6-mo intervention Exclusion criteria： * Systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg * Total cholesterol ≥ 239 mg/dL * Low-density lipoprotein cholesterol ≥ 159 mg/dL * Triglycerides ≥ 199 mg/dL * Blood glucose ≥ 110 mg/dL * Change in body weight exceeding ± 10% during the prior year * Energy intake is too low or too high * Unwillingness or special requirement for diet that could not be modified * Poor adherence during the recruiting meeting or unsatisfactory completion of keeping food diary or filling questionnaire at any time before randomization * Eating disorder or any psychosocial or scheduling factors that could impede study outcomes * Have a history of diagnosed CVD, diabetes, cancer or inflammatory diseases * Have a history of a mental illness * Have diagnosed endocrine, pulmonary or hematological disease * Have diagnosed bowel disease or malabsorption that would prevent the participants from complying with the dietary restrictions of the feeding trial * Renal or liver insufficiency * Other chronic disease thought to interfere with the effect of the diet or with participation or adherence * Current use of supplements or anti-inflammation medications or medications affecting glucose, lipid metabolism and blood pressure * Smoking or alcoholic beverage intake \>1 times per week * Current or planned pregnancy prior to end of study, or breast-feeding * Irregular menstrual cycles * Have birth control medication