Objectives A high soft drink intake may promote, whereas intake of cheese may reduce risk of the metabolic syndrome (MetS), but will cheese intake blunt the soft drink versus MetS association?

Design Cross-sectional study.

Setting The Oslo Health Study.

Participants Among the 18 770 participants of the Oslo Health Study there were 5344 men and 6150 women having data on cheese and soft drink intake and on risk factors for MetS, except for fasting glucose. The MetSRisk index=the weighted sum of triglycerides (TG), systolic blood pressure, diastolic blood pressure, waist circumference and body mass index (BMI) divided by high-density lipoprotein (HDL) were used as a combined risk estimate to examine the cheese/soft drink versus MetS interaction, and the SumRisk index was used to assess whether increasing intake of soft drinks/cheese would include an increasing number of MetS factors being above the cut-off values. We analysed the data using non-parametric correlation and analysis of covariance (ANCOVA).

Results In all three groups of soft drink intake (seldom/rarely, 1–6 glasses/week, ≥1 glass/day), there was a negative cheese versus MetSRisk correlation (p≤0.003), but in the highest intake group the influence of cheese seemed to level off, suggesting interaction. However, there was no interaction between cheese and soft drinks within the fully adjusted models. Conversely, at all four levels of cheese intake, MetSRisk increased with an increasing intake of soft drinks (p≤0.001 at all cheese levels). Similar associations were found with the SumRisk index. When controlling for a large number of covariates (eg, sex, age group, smoking, education, physical activity, intake of fruits/berries and vegetables), the above associations prevailed.

Conclusions Cheese intake blunted the association between soft drink intake and MetS, an influence possibly related to fatty acid desaturation, or to undetected covariates.