Background To estimate the prevalence of overweight and obesity in the Spanish population as measured with body mass index (BMI), waist circumference (WC) and waist to height ratio (WHtR) and to determine the associated cardiovascular risk factors. Methods Pooled analysis with individual data from 11 studies conducted in the first decade of the 21st century. Participants aged 35–74 years were asked about the history of cardiovascular diseases, hypertension, diabetes and hypercholesterolemia. Height, weight, WC, blood pressure, glycaemia, total cholesterol, low-density and high-density lipoprotein cholesterol and coronary risk were measured. The prevalence of overweight (BMI 25–29.9 kg/m2), general obesity (BMI ≥30 kg/m2), suboptimal WC (≥ 80 cm and < 88 in women, ≥ 94 and < 102 in men), abdominal obesity (WC ≥88 cm ≥102 cm in women and men, respectively) and WHtR ≥0.5 was estimated, standardized for the European population. Results We included 28,743 individuals. The prevalence of overweight and suboptimal WC was 51% and 30% in men and 36% and 22% in women, respectively; general obesity was 28% in both sexes and abdominal obesity 36% in men and 55% in women. The prevalence of WHtR ≥0.5 was 89% and 77% in men and women, respectively. All cardiovascular risk factors were significantly associated with abnormal increased values of BMI, WC and WHtR. Hypertension showed the strongest association with overweight [OR = 1.99 (95% confidence interval 1.81-2.21) and OR = 2.10 (1.91-2.31)]; suboptimal WC [OR = 1.78 (1.60-1.97) and OR = 1.45 (1.26-1.66)], with general obesity [OR = 4.50 (4.02-5.04), and OR = 5.20 (4.70-5.75)] and with WHtR ≥0.5 [OR = 2.94 (2.52-3.43), and OR = 3.02 (2.66-3.42)] in men and women respectively, besides abdominal obesity in men only [OR = 3.51 (3.18-3.88)]. Diabetes showed the strongest association with abdominal obesity in women [OR = 3,86 (3,09-4,89). Conclusions The prevalence of obesity in Spain was high. Overweight, suboptimal WC, general, abdominal obesity and WHtR ≥0.5 was significantly associated with diabetes, hypertension, hypercholesterolemia and coronary risk. The use of lower cut-off points for both BMI and particularly WC and could help to better identify the population at risk and therefore achieve more effective preventive measures.