**Background:** The nutritional transition in sub-Saharan Africa, characterized by increased consumption of refined, high-fat, high-sugar foods, is contributing to rising rates of obesity and non-communicable diseases. In Benin, diabetes prevalence was 7% in 2014, high blood pressure 28% in 2015, and obesity affected 23% of women and 6% of men in 2016. Pulses, particularly cowpea—the most frequently consumed legume in West Africa—are rich in dietary fibre, protein, minerals, and B vitamins, and may help prevent metabolic disorders. However, concerns exist that urbanization and lengthy preparation times may reduce cowpea consumption. This study aimed to update data on cowpea consumption patterns in South Benin and estimate the nutritional contribution of cowpea-based dishes to recommended nutrient intakes (RNI).
**Methods:** A cross-sectional survey was conducted among 1,217 adults (19–65 years) in three municipalities: Cotonou (urban, ~680,000 inhabitants, surveyed late 2017), Adjohoun and Allada (rural, ~75,000 and ~128,000 inhabitants, surveyed early 2019). Representative two-step random cluster sampling was used. A food frequency questionnaire (FFQ) was developed and validated for nine traditional cowpea-based dishes: three doughnuts (Ata, Ata-doco, Ataclè), three mixed dishes (Abla, Atassi, Djongoli), and three stews (Adowè, Abobo, Vêyi). A food atlas with photographs of four portion sizes per dish was created and validated against weighed records (Spearman's r: 0.2–0.8). The FFQ was validated against three 24-hour recalls (concordance: 66–96% by Bland-Altman method). The nine dishes were sampled from 27 street food vendors in Cotonou and analyzed for proximate composition, minerals (ICP-OES), total dietary fibre (enzymatic-gravimetric), folate (microbiological assay), and thiamine (UPLC). Daily nutrient intakes were calculated and compared to FAO/WHO RNI values.
**Key Results:** Nearly all respondents (98%) reported regular cowpea consumption, with >70% consuming at least once per week. The most consumed dishes were Atassi (mixed cowpea-rice dish) and Abobo (stew). Consumption frequency ranged from 0.1 to 2.4 times/week per dish, with overall mean consumption of ~7 times/week (approximately once daily). Mean portion sizes varied: Abobo, Atassi, and Djongoli were consumed in larger quantities (272–311 g/meal), while doughnuts and Adowè were consumed in smaller portions. Mean daily cowpea seed equivalent intake was 71 g in urban and 58 g in rural areas (p<0.05). With cowpea consumption alone, 51.5% (urban) and 49.7% (rural) of the population reached the EAT-Lancet recommendation of ≥50 g pulses/day. Nutritional composition varied significantly among dishes: protein 3.0–9.9 g/100g, dietary fibre 2.7–7.2 g/100g, lipids 0.4–33.3 g/100g, magnesium 13–68 mg/100g, potassium 90–500 mg/100g, zinc 0.3–1.6 mg/100g, iron 0.4–8 mg/100g, thiamine 28–175 µg/100g, and folate 12–84 µg/100g. The mean daily contribution of cowpea-based dishes to RNI was: 42% for dietary fibre, 37% for magnesium, 30% for folate, 26% for protein, 18% for zinc, 17% for potassium, and ~15% for energy. Contributions to calcium, iron, and thiamine were below 15%. Abobo stew contributed the most to RNI across nutrients. A positive association was found between the number of different cowpea dishes consumed and total seed equivalent intake (R=0.64 rural, 0.81 urban).
**Clinical Implications:** Regular cowpea consumption in southern Benin provides substantial contributions to dietary fibre (42% RNI), magnesium (37%), and folate (30%) intakes, which may help prevent obesity, type 2 diabetes, cardiovascular disease, and neural tube defects. The high fibre content supports satiety and metabolic health. However, contributions to iron and calcium are low, likely due to phytate content reducing bioavailability. The finding that 49.7–51.5% of the population meets the EAT-Lancet pulse recommendation through cowpea alone underscores its nutritional importance. The positive association between dietary diversity and total cowpea intake suggests that maintaining a variety of traditional cowpea dishes promotes higher consumption. These findings support public health strategies to maintain and encourage traditional cowpea consumption patterns, counteracting the nutritional transition toward refined, low-fibre foods.