Consumption of Restructured Meat Products with Added Walnuts Has a Cholesterol-Lowering Effect in Subjects at High Cardiovascular Risk: A Randomised, Crossover, Placebo-Controlled Study

Abstract

Background: Diet and lifestyle are modifiable factors involved in the development and prevention of non-communicable diseases, including cardiovascular disease. Nut consumption, particularly walnut intake, has been inversely related to incident coronary heart disease (CHD) in observational studies and to improved lipid profiles in short-term feeding trials.Objective: To assess the potential functional effect associated with the regular consumption of walnut-enriched restructured meat products in subjects at risk for cardiovascular disease (CVD).Design: A crossover single-dose bioavailability study (n = 3) using γ-tocopherol as exposure marker and a crossover unblinded dietary intervention study (5 weeks) in subjects at risk (n = 25). Dietary intervention consisted of regular consumption of the meat product, with or without walnuts, five times per week for five weeks with a 1-month washout in between. Overnight fasting blood samples were collected on days 0, 12, 21, 28 and 35, coinciding with blood pressure and body weight recordings. Participants were asked to complete a diet record throughout the study. The functional effects were assessed using clinically relevant and related biomarkers of CHD: serum total, HDL and LDL cholesterol, triacylglycerols, homocysteine, vitamins B6 and B12, folic acid, α-tocopherol and platelet function test (obturation time).Results: The regular consumption of walnut-enriched meat products compared with that of the restructured meat products without added walnuts provokes a decrease in total cholesterol of 6.8 mg/dl (CI95%: −12.8, −0.85). Compared to baseline (mixed diet), meat products with walnuts decreased total cholesterol (−10.7 mg/dl, CI95%: −17.1, −4.2), LDL cholesterol (−7.6 mg/dl, CI95%: −2.2, −13.0) and body weight (−0.5 kg, CI95%: −0.1, −0.9) and increased γ-tocopherol (8.9 mg/dl, CI95%: 1.0, 16.8).Conclusions: The restructured meat products with added walnuts supplied in this study can be considered functional foods for subjects at high risk for CVD, as their regular consumption provokes a reduction in total cholesterol of 4.5% with respect to baseline values (mixed diet) and 3% with respect to the restructured meat without walnuts.