Effects of a Legume-rich Diet in the Context of the Planetary Health Diet Compared to a Western-oriented Dietary Pattern in Participants with Increased Cardiometabolic Risk

The aim of the study is to systematically investigate the effects of a diet enriched with legumes in the dietary pattern approach (Planetary Health Diet) compared to a control diet low in legumes in older people with a risk phenotype for cardiovascular and neurodegenerative diseases. For this purpose, a controlled, six-week nutritional intervention study will be carried out in a parallel design. A total of 100 subjects (aged 50 - 75 years) will be randomly assigned to one of two intervention groups: i) a legume-rich diet based on the Planetary Health Diet, with a focus on plant protein, ii) a diet based on the Western dietary pattern including animal protein sources (= control diet). The target variables include parameters of lipid, glucose and insulin metabolism as well as biomarkers of inflammation and endothelial activation, proteomics and neurodegeneration markers. Furthermore, pulse wave velocity is measured to assess vascular function and neuropsychological target variables (e.g. hunger, satiety) are recorded using questionnaires. The subjects come to the study center for examination before the start of the intervention (visit 1), after three weeks (mid-intervention, visit 2) and after six weeks (end of intervention, visit 3).

Inclusion criteria

• written informed consent
• Non-smoking
• BMI: 27 - 34,9 kg/m2
• Waist circumference (women ≥ 80 cm, men ≥ 94 cm)
• Systolic blood pressure: ≥ 120 mmHg, diastolic blood pressure: ≥ 80 mmHg
• At least one of the following criteria:
• Fasting triglycerides in serum: ≥ 150 mg/dL
• Fasting LDL cholesterol in serum ≥160 mg/dL
• Fasting HDL-Cholesterol in serum: women < 50 mg/dl, men < 40 mg/dL
• Fasting glucose in plasma: ≥ 100 mg/dL
• CRP in serum 0,2-3 mg/dL

Exclusion criteria

• food intolerances and allergies (especially legumes)
• Smoking
• malabsorption syndromes
• thyroid diseases
• impaired renal function
• chronic liver disease
• heart failure
• myocardial infarction
• insulin-dependent diabetes mellitus
• chronic inflammatory diseases
• tumors
• anemia
• immunosuppression
• intake of supplements (e.g., fish oil)
• Participation in another study
• other exclusion criteria at the discretion of the physician/ investigator