Effect of Low Valine Diet on Body Weight and Metabolic Parameters

This study is a randomized, double-blind, controlled clinical study, which aims to explore the advantages of low valine meal replacements in weight loss and improving metabolism compared with ordinary meal replacements. It is divided into two parts: 1) short-term continuous low valine meal replacement intervention (2 weeks) and 2) long-term intermittent low valine meal replacement intervention (16 weeks). Overweight and obese subjects will be enrolled according to the inclusion and exclusion criteria, and entered the short-term continuous intervention and long-term intermittent intervention projects according to the subjects' wishes until the number of subjects planned for the project is filled. The subjects of the short-term 2-week continuous intervention and long-term 16-week intermittent intervention studies will be randomly assigned to the control meal replacement group and the low valine meal replacement group by random allocation, with 12 people in each group.

The randomization sequence of this study will be generated by an independent statistician team based on the clinical research plan and random allocation parameter configuration file. During the generation process, all necessary information and related parameters, including system software version, random number seed, sequence length, block length, group information, inter-group ratio, stratification factors and levels, will be recorded in detail in the randomization table to ensure the reproducibility and reliability of randomization. All subjects and investigators (including members of the research team and the intervention implementers) are blind to the grouping of subjects during the study period.

The primary outcome is the change of body weight, which will be measured at baseline and at the end of follow-up. Secondary endpoints include changes in plasma glucose, serum lipid profiles, liver enzymes, and DXA body composition. For patients with long-term low-valine meal replacement intervention, liver fat content measured by PDFF will also be measured. At the same time, serum proteomic, metabolomic and lipidomic profiles of all subjects at the end of follow-up will be analyzed to preliminarily expand the study of the possible mechanism of low valine diet in regulating body weight.

Inclusion criteria

• Male or female, 16 years old ≤ age ≤ 80 years old;
• BMI ≥ 24kg/m2

Exclusion criteria

• Excessive drinkers (defined as: in the past 6 months, the weekly alcohol intake of men exceeds 140g, and that of women exceeds 70g);
• Liver diseases caused by other reasons: such as alcoholic liver disease, acute and chronic viral hepatitis, drug-induced, immune hepatitis (AMA, SMA, ANA), cirrhosis, liver cancer, etc.;
• Other diseases that affect glucose and lipid metabolism: hyperthyroidism, hypothyroidism, Cushing's syndrome, etc.;
• Poorly controlled diabetic patients: HbA1c >9.5% within three months; or use of hypoglycemic drugs that may affect weight, including pioglitazone, GLP-1, SGLT2 inhibitors;
• Chronic kidney disease or severe renal impairment, defined as serum creatinine greater than 2.0mg/dL;
• Serum ALT greater than 3 times the upper limit of normal;
• Life expectancy of no more than 3 years in the presence of serious health conditions;
• Those who plan to get pregnant in the near future;
• Those who cannot participate in the follow-up of the intervention due to other conditions;
• Continuously used drugs that may cause weight changes for more than 2 weeks in the past year (such as glucocorticoids, thyroid hormones, etc.);
• Participated in other clinical trials in the past 4 weeks;
• Those who had gastric volume reduction surgery or digestive tract surgery;
• Those diagnosed with any tumor disease;
• Subjects who participated in strenuous exercise or planned to change their diet structure;
• Unable to sign the informed consent form.