Effect of Isoenergetic Substitution of Cheese with Other Dairy Products on Blood Lipid Markers in the Fasted and Postprandial State: An Updated and Extended Systematic Review and Meta-Analysis of Randomized Controlled Trials in Adults
Rebecca Pradeilles, Tom Norris, Laury Sellem, Oonagh Markey
Abstract
Consumption of fat as part of a cheese matrix may differentially affect blood lipid responses, when compared to other dairy foods. This systematic review was conducted to compare the impact of consuming equal amounts of fat from cheese and other dairy products on blood lipid markers in the fasted and postprandial state. Searches of PubMed (Medline), Cochrane Central and Embase databases were conducted up to mid-June 2022. Eligible human randomized controlled trials (RCTs) investigated the effect of isoenergetic substitution of hard or semi-hard cheese with other dairy products on blood lipid markers. Risk of bias was assessed using the Cochrane RoB 2.0 tool. Random-effects meta-analyses assessed the effect of ≥2 similar dietary replacements on the same blood lipid marker. Of 1,491 identified citations, 10 articles were included (risk of bias: all some concerns). Pooled analyses of 7 RCTs showed a reduction in fasting total cholesterol, LDL-cholesterol and HDL-cholesterol concentrations following ≥ 14 d mean daily intake of 135 g cheese (weighted mean difference (WMD): −0.24 mmol/L; 95% CI: −0.34, −0.15; I2 = 59.8 %, WMD: −0.19 mmol/L; 95% CI: −0.27, −0.12; I2 = 42.8%, and WMD: −0.04 mmol/L; 95% CI: −0.08, −0.00; I2 = 58.6%, respectively) relative to ∼52 g/d butter. We found no evidence of a benefit from replacing cheese for ≥ 14 d with milk on fasting blood lipid markers (n = 2). Limited postprandial RCTs, described in narrative syntheses, suggested that cheese-rich meals may induce differential fed-state lipid responses compared to some other dairy matrix structures, but not butter (n ≤ 2). In conclusion, these findings indicate that dairy fat consumed in the form of cheese has a differential effect on blood lipid responses relative to some other dairy food structures. However, owing to considerable heterogeneity and limited studies, further confirmation from RCTs is warranted. This systematic review protocol was registered at https://www.crd.york.ac.uk/PROSPERO/ as CRD42022299748.