Unprocessed and Processed Meat Consumption and Blood Pressure: The INTERMAP Study

Background: Evidence from prospective cohort studies indicates that consumption of processed meats is associated with higher incidence of CHD. Processed meats are high in saturated fatty acids, cholesterol, and preservatives including sodium that may unfavorably influence blood pressure (BP), but evidence is limited. We therefore investigated associations with BP of unprocessed and processed meat consumption, including types of processed meats. Methods: We used cross-sectional data from the INTERMAP Study on 4,680 men and women aged 40-59 years from Japan, China, UK, and US. During four visits, eight BPs and four 24-hr dietary recalls were collected. Processed meats included preserved meats; fresh processed meats (ready-made, salted, and/or spiced, no curing), bacon, ham (cured and cooked), cold cuts and sausages, and canned meat products. Country-specific linear regression coefficients were estimated and pooled, weighted by inverse of their variance. Adjustments were made for demographic (age, gender, sample), lifestyle (total energy, alcohol, smoking, education, supplement use, adherence to special diet, low-fat dairy, fruit, vegetables, fiber-rich grain products, fish and shellfish), and clinical confounders (history of cardiovascular diseases or diabetes, family history of hypertension, use of anti-hypertensive, cardiovascular, or diabetes medication, BMI). The influence of adjustment for urinary sodium, total cholesterol, and total saturated fatty acids was additionally investigated. Results: Average daily unprocessed/processed meat consumption (g/1000 kcal) was 41/10 in Asian participants and 82/47 in Western participants. In Western participants, processed meats comprised fresh processed meat (36%), cold cuts and sausages (34%), ham (16%), and bacon (7%). Meat consumption was not associated with BP in Asian participants. After adjustment for demographic and lifestyle factors, significant associations with systolic BP were observed per each 50 g/1000 kcal higher intake of unprocessed (+1.19 mm Hg, P=0.02) and processed (+2.00 mm Hg, P=0.01) meat consumption in Western participants. However, these associations attenuated and did not remain significant after adjustment for BMI. We further examined types of processed meat in Western participants. Consumption of cold cuts and sausages higher by 12,5 g/1000 kcal was associated with a systolic BP difference of +0.72 mm Hg (P=0.02). Consumption of ham higher by 12,5 g/1000 kcal was associated with a systolic BP difference of -0.92 mm Hg (P=0.03). These associations prevailed after adjustment for urinary sodium excretion, intakes of saturated fatty acids, and total cholesterol. Conclusion: Unprocessed and processed meat consumption was not associated with BP, however, some types of processed meat may influence BP in opposite directions.