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Department of Nutritional Sciences University of Toronto Toronto, Ontario M5S 3E2 Canada E-mail: thomas.wolever{at}utoronto.ca
Dear Sir:
Christensen at al (1) describe a randomized trial showing that abstaining from coffee reduced serum cholesterol by 0.28 mmol/L, an effect they suggest is due to terpenoids in coffee. However, I cannot find any comments in the paper about whether the subjects in the study took milk or cream in their coffee. I recently quit drinking coffee at work and as a result reduced my intake of milk by 500 mL (2 cups)/d. It seems to me that the reduction in cholesterol could have been due, at least in part, to a reduction in saturated fat intake resulting from not drinking the milk or cream otherwise used in coffee. The subjects in this study stopped drinking an average of nearly 5 cups (875 mL) coffee/d. If they were using 30 mL whole milk/cup, they reduced their milk intake by 150 mL/d, an amount that contains 5 g fat, of which 60% is saturated. Assuming an energy intake of 8.4 kJ/d, reducing milk intake by 150 mL/d and replacing it with water or juice would reduce saturated fat by nearly 1.5% of energy. According to the Key's equation (2), this would be expected to reduce serum cholesterol by 0.1 mmol/L, or 35% of the observed effect of coffee. If the subjects used cream in their coffee, then the reduction in saturated fat intake could be 2–3 times more than that for milk and might account for the entire effect Christensen et al observed. Of course, if Norwegians like their coffee black, then these musings are nothing more than that!
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