New meta-analysis: cheese consumption and cardiovascular health

Cheese is a much-loved product by many people. Besides, cheese naturally contains essential nutrients, like protein, calcium and vitamin K and is therefore part of a balanced diet and lifestyle. Cheese consumption also contributes to the intake of (saturated) fat. Scientists have done many research on the effect of cheese consumption on cardiovascular health. A new meta-analysis by Chen et al (2017) shows that cheese consumption seems to be beneficially associated with cardiovascular health; the researchers also performed a dose-response analysis to gain more insight in quantifying an ‘optimal’ daily portion.

Summary | A meta-analysis by Chen et al. (2017) shows that the consumption of cheese is beneficially associated with cardiovascular health. Furthermore, a dose-response analysis shows that the strongest association is found with a daily portion of 40 gram cheese. This is about two servings a day.

Milk is included in dietary recommendations worldwide and is part of a healthy and varied diet. Milk and other dairy products naturally provide nutrients that we need on a daily basis, such as protein and calcium. Semi-hard cheeses are naturally rich in protein, calcium, phosphorus, zinc, vitamin B12 and vitamin K (1). On the other hand cheese also contains fat and the consumption of cheese contributes to people’s (saturated) fat intake.

As discussed by the researchers Chen et al. (2017) (2); the intake of saturated fat is associated with higher LDL-cholesterol levels, which is a recognized risk factor for cardiovascular health. As saturated fat increases the LDL cholesterol level, it is generally recommended to replace saturated fatty acids with polyunsaturated fatty acids. Therefore, it is recommended to consume semi-skimmed or skimmed dairy products.

New meta-analysis: cheese consumption and cardiovascular healthHowever, studies on the consumption of dairy products with different fat percentages do not show any adverse results for heart health, even though it was initially expected there would be an association with the amount of saturated fat in dairy. (3) Therefore much research has been undertaken over the past 20 years to investigate the effect of cheese consumption on cardiovascular health (2). Recent meta-analysis (4-6) have shown that there is a neutral or small beneficial association between cheese consumption and cardiovascular health. Chen et al. (2017) performed a dose-response analysis to further quantify the association (2).

Study characteristics

The researchers carried out a literature search between January and December 2015. After the search and selection process 15 prospective studies were included in the meta-analysis by Chen et al. (2017). The selected studies have been carried out in Europe (n=10), the United States (n=4) and Australia (n=1). The follow up time was more than 10 years in 13 out of 15 studies and in 14 out of 15 studies subjects with cardiovascular diseases at the start of the study were excluded. (2)

Results

The following results have been obtained by the researchers:

  • High cheese consumption seems to be beneficially associated with cardiovascular health (RR=0.90; 95% CI = 0.82-0.99). (2).
  • To further quantify this association the researchers performed a dose-response analysis, based on 2 studies. They observed a tendency for a U-shaped association between cheese consumption (0-100 gram/day) and overall cardiovascular health. The strongest association was found with a daily cheese intake of 40 gram (2). This about two servings a day.

Conclusion

Chen et al. (2017) conclude that cheese consumption is beneficially associated with cardiovascular health: “This meta-analysis of prospective studies suggests a nonlinear inverse association between cheese consumption and risk of CVD”. A dose-response analysis shows that the strongest association is found with a daily portion of 40 gram cheese. (2)

Remarks

The researchers also reported some study limitations. The studies included in the meta-analysis were observational studies and so, unknown confounders could have had an impact on the outcome. The selected studies have used self-reported food frequency questionnaires, which may have led to a misclassification of the cheese consumption. Also whether the effects of cheese consumption varies according to fat content of the cheese was not well addressed due to the limited data.

Therefore, the researchers concluded that the results must be interpreted with caution. Further large scale prospective cohort studies are needed to investigate the association between cheese consumption and cardiovascular health in more depth, especially comparing full-fat with low-fat cheese.

Reference

  1. EFSA Food Composition database and Dutch food composition database (NEVO-online 2016/5.0).
  2. Chen et al. (2017). Cheese consumption and risk of cardiovascular disease: a meta‑analysis of prospective studies. European Journal of Nutrition, 2017; 56: 2565-2575.
  3. Thorning et al (2017). Whole dairy matrix or single nutrients in assessment of health effects: current evidence and knowledge gaps. American Journal of Clinical Nutrition, 2017 doi: 10.3945/ajcn.116.151548
  4. Hu et al. (2014). Dairy foods and risk of stroke: a meta-analysis of prospective cohort studies. Nutrition, Metabolics and Cardiovascular Disease, 2014; 24: 460-469.
  5. Qin et al. (2015). Dairy consumption and risk of cardiovascular disease: an updated meta-analysis of prospective cohort studies. Asia Pacific Journal of Clinical Nutrition, 2015; 24: 90-100.
  6. Drouin-Chartier et al (2016). Systematic review of the association between dairy product consumption and risk of cardiovascular-related clinical outcomes. Advances in Nutrition, 2016; 7: 1026-1040Clin Nutr 24:90–100