Consumer analysis of the sensory impact of light exposure and age on fluid milk

Context: Cheese may affect lipids and lipoproteins differently than other high-fat dairy foods. Objective: The present systematic review and meta-analysis was performed to evaluate randomized controlled trials that examined the effect of cheese consumption compared with another food product on blood lipids and lipoproteins. Data Sources: A systematic literature search of the MEDLINE, Embase, Scopus, CAB, Abstracts, the Cochrane Controlled Trials Register, and the clinicaltrials.gov website was performed. Study Selection: A total of 12 randomized controlled trials (RCTs) were identified that examined the effect of cheese consumption on blood lipids and lipoproteins in healthy adults. Data Extraction: A meta-analysis of 5 RCTs that compared the effects of hard cheese and butter, both of which had a similar ratio of polyunsaturated fatty acids to saturated fatty acids (P/S ratio), was performed. Data Synthesis: Compared with butter intake, cheese intake (weighted mean difference: 145.0 g/d) reduced low-density lipoprotein cholesterol (LDL-C) by 6.5% (-0.22mmol/l; 95%CI: -0.29 to -0.14) and high-density lipoprotein cholesterol (HDL-C) by 3.9% (-0.05mmol/l; 95%CI: -0.09 to -0.02) but had no effect on triglycerides. Compared with intake of tofu or fat-modified cheese, cheese intake increased total cholesterol or LDL-C, as was expected on the basis of the P/S ratio of the diets. There was insufficient data to compare intake of cheese with intake of other foods. Conclusions: Despite the similar P/S ratios of hard cheese and butter, consumption of hard cheese lowers LDL-C and HDL-C when compared with consumption of butter. Whether these findings can be attributed to calcium, specific types of saturated fatty acids, or the food matrix of cheese warrants further research. Subject Matter Expert Comment – Moises Torres-Gonzales, Ph.D. It is normally thought that consuming foods with high saturated fat content, such as cheese, increase the risk of CVD, because saturated fat elevates blood lipids levels. However, scientific studies have demonstrated that cheese intake is associated with reduced risk of CVD. By focusing on the effects of cheese on blood lipids levels, this study shows that in general, cheese does not have a negative impact on the levels of TC, LDL-C and HDL-C. It is important to mention that cheese is not only saturated fat but also a source of unsaturated fat, calcium and other substances that may exert beneficial effects against CVD. Contribution to the State of Science Lowering the intake of saturated fat and sodium has been recommended because they have been associated with increasing LDL-cholesterol (LDL-C) and blood pressure (BP), respectively. Elevated LDL-C and high BP are considered independent risk factors for cardiovascular disease (CVD). Cheese is one of the main contributors of saturated fat and sodium in the diet of Western countries and thus, it might be thought that cheese intake increases the risk of CVD. However, several human clinical trials have reported that cheese intake affects blood lipid differently compared to other dairy products despite the same fat content (Tholstrup et al. 2004. J Am Coll Nutr 23:169-176; Biong et al. 2004. Br J Nutr 92:791-797; Nestel et al. 2005. Eur J Clin Nutr 59:1059-1063; Hjerpsted et al. 2011. Am J Clin Nutr 94:1479-84). Additionally, observational studies have found that cheese intake is associated with reduced risk of CVD (Warensjo et al., Am J Clin Nutr 2010;92:194-202; Qin et al. Asia Pac J Clin Nutr 2015;24(1):90100). Therefore, the aim of this study was to conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) on the relationship between cheese and blood lipids and lipoproteins. The main findings of the study indicate that when cheese is compared with nodairy foods with different polyunsaturated-saturated fat ratios (P/S ratio) -e.g. tofu or fatmodified cheesecheese tends to increase total cholesterol (TC) and LDL-C. In contrast, when cheese is compared to butter with similar P/S ratio, cheese consistently lowers TC, LDL-C and HDL-C. In summary, the effect of cheese on blood lipids will depend on the product with which that cheese is compared. Importance to Industry For Thought Leaders/Health Professionals: Despite the fat content, cheese consumption does not negatively affect blood lipid levels.