Obesity causes chronic inflammation, which promotes atherosclerosis and cardiovascular disease. Previous research suggests that spices such as cinnamon, cumin, and ginger exert short-term anti-inflammatory effects; however, studies with longer durations are needed to confirm these findings. Authors of a recent study found that four weeks of spice consumption reduced inflammation and altered monocyte function in adults at risk of cardiometabolic disease.

Monocytes are white blood cells that respond to infection by promoting inflammation. Obesity and dyslipidemia cause inappropriate activation of monocytes, promoting chronic inflammation in the arteries. Pro-inflammatory monocytes carrying excess lipids, called foam cells, accumulate in arterial walls, narrowing the arteries and restricting blood flow. Consuming spices that contain anti-inflammatory bioactive compounds may help reduce cardiovascular disease risk.

The authors recruited 71 participants and assigned them to consume a standard American diet with added spices in three doses: low (a dash), medium (a quarter teaspoon), or high (a half teaspoon). Participants consumed each dose of spices for four weeks and completed the doses in random order. The spice mixture contained the most common spices used in the United States, the most abundant of which were cinnamon, coriander, ginger, cumin, and parsley. Participants provided blood samples at multiple points throughout the study. Finally, the investigators isolated monocytes from the participants’ blood and exposed the cells to bacterial endotoxin in order to promote inflammation.

Compared to baseline, participants had lower fasting serum levels of the pro-inflammatory cytokine interleukin-6 following four weeks of the medium dose spice blend. The monocytes from these participants also secreted less interleukin-6 when challenged with bacterial endotoxin. Participants consuming the medium and high spice blends had fewer foam cells and more conventional monocytes than participants consuming the low spice blend.

The authors concluded that spices reduced fasting inflammation and altered monocyte behavior. They did not know why the medium dose was more effective in reducing inflammation than the high dose, but they hypothesized that the high dose of spices may have contained such a high level of polyphenols that it promoted oxidative stress. More research is needed to test this hypothesis. This study was funded by the McCormick Science Institute.

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