How do everyday spices help protect the heart?

By Vijay Kumar MalesuReviewed by Susha Cheriyedath, M.Sc.May 27 2026

Could a few extra grams of herbs and spices each day improve blood pressure, inflammation, and gut bacteria? A new review of controlled studies suggests these everyday ingredients may offer more than just flavor.

Study: Cardiometabolic and Microbiome Effects of Spices and Herbs. Image Credit: BT1976 / Shutterstock

In a recent supplement article published in the journal Nutrition Reviews, the review authors summarized evidence from several previously published controlled studies examining how regular consumption of culinary spices and herbs affects cardiometabolic risk markers, blood pressure, and gut bacteria in adults at cardiometabolic risk.

Background

Cardiovascular disease remains the leading cause of death worldwide, despite advances in medicine and public health. Dietary patterns high in saturated fat, sugar, and processed foods can contribute to high blood pressure, diabetes, obesity, and chronic inflammation, which increase the risk of cardiovascular disease.

Many common cooking ingredients, such as cinnamon, turmeric, garlic, oregano, and ginger, contain natural bioactive compounds that have been shown to provide antioxidant effects and reduce inflammation.

The review authors noted that scientists have increasingly explored whether these everyday ingredients can improve heart and metabolic health naturally. Further research is needed to determine the most effective combinations and doses for long-term cardiovascular risk reduction.

Evidence from post-meal spice studies

The review authors first summarized earlier studies that explored how spices and herbs affect the body immediately after eating high-fat meals, which are known to temporarily increase inflammation, triglycerides, and oxidative stress. In a previously published postprandial study, overweight participants consumed a meal containing black pepper, cinnamon, cloves, garlic powder, ginger, oregano, paprika, rosemary, and turmeric. There was a significant reduction of insulin levels (21%) and triglycerides (31%) when compared with the control meal in the post-meal period. Additionally, the meal was found to increase antioxidant activity in the blood.

Another previous study investigated whether psychological stress altered these protective effects. Participants consumed a high-fat meal with or without spices and then completed stressful tasks such as public speaking and mental arithmetic. The spice mixes reduced post-meal triglyceride levels under resting conditions, but this benefit disappeared during stress. The laboratory analysis showed that specific spices inhibited lipase and phospholipase A2, enzymes that play a role in fat digestion. However, stress appeared to interfere with these positive metabolic responses, highlighting how emotional stress can affect digestion and cardiovascular health.

Evidence from lower-dose culinary spice trials

The review then described a pilot trial examining whether smaller culinary doses of spices and herbs could still provide measurable benefits. Participants were given a meal containing no spices, 2 grams of spice blend, and 6 grams of spice blend. The meal containing 6 grams significantly reduced the decline in flow-mediated dilation, a measure of blood vessel function that can worsen after high-saturated-fat, high-carbohydrate meals.

Another major area of research was inflammation, as chronic low-grade inflammation can lead to heart disease, diabetes, and obesity. In a related postprandial analysis, investigators assessed the levels of inflammation-related markers in blood samples from participants after they had eaten meals containing spices. The meal containing 6 grams of spices resulted in a significant reduction in the release of selected inflammatory cytokines from LPS-stimulated immune cells (e.g., interleukin-1 beta, interleukin-8, and tumor necrosis factor alpha). The results suggest that incorporating herbs and spices into daily meals may reduce the effects of unhealthy foods on inflammation.

Evidence from a 4-week controlled-feeding trial

The review authors also summarized a subsequent controlled-feeding trial that investigated whether these benefits persisted with long-term consumption in adults at increased risk for cardiometabolic disease. Each participant consumed an average American diet of low-, moderately-, or heavily seasoned foods over four weeks (heavy seasoning was defined as 6.6 grams of seasonings per day on a 2,100-calorie diet). Blood pressure, cholesterol levels, inflammatory markers, glucose metabolism, and vascular function were measured.

The most important finding was that the high-spice diet lowered 24-hour systolic blood pressure compared with the moderate-spice diet and lowered 24-hour diastolic blood pressure compared with the low-spice diet. Interestingly, clinic blood pressure measurements did not change substantially, suggesting that continuous ambulatory monitoring may better capture subtle cardiovascular improvements. These findings indicated that adding herbs and spices to the diet each day may be an easy way to help support cardiometabolic health without significant dietary change.

Secondary and exploratory findings on immune function, phytochemicals, and the gut microbiome

The review also covered secondary and exploratory analyses on how spices and herbs affect immune function. It was observed that the moderate-spice diet reduced interleukin-6 levels in plasma and in LPS-stimulated immune cell culture supernatants, which are related to cardiovascular disease and metabolic disorders. When examined, the original investigators noted that the high level of spice eating modified the behavior of monocytes (white blood cells that play a role in forming plaque in arteries). These results suggested that spices may reduce cardiovascular risk, in part, by calming immune system activity and limiting inflammatory damage to arteries.

The review authors further discussed analyses of phytochemical metabolites in blood samples. Spices and herbs contain various phytochemicals, including flavonoids, terpenoids, and phenolic acids. Over 90 metabolites were observed after regular consumption of spices like black pepper, rosemary, garlic, cinnamon, and ginger. These metabolites may help explain some of the observed cardiometabolic effects, but further analyses are needed to link them directly with outcomes such as blood pressure and endothelial function.

One more significant finding summarized in the review concerned the gut microbiome: adults on higher-spice diets had more bacterial groups often associated with beneficial metabolic functions, Ruminococcaceae and Agathobacter. They produce short-chain fatty acids, which support good gut health. As bacteria in the intestines affect inflammation, metabolism, and immune function, these findings suggest that culinary spices and herbs may modulate gut bacterial composition in potentially beneficial ways, although direct clinical gut-health effects require further study.

Conclusion

The findings reviewed in the article show that culinary spices and herbs may improve several important markers of cardiovascular and metabolic health. Acute meal studies showed improvements in postprandial triglycerides, insulin, antioxidant measures, inflammatory responses, and endothelial function, while the 4-week feeding trial showed improvements in ambulatory blood pressure and selected immune and microbiome markers.

The reviewed evidence also suggested that spices affected the activity of the immune system, as well as produced phytochemical metabolites that could provide cardiometabolic benefits. 

These findings are relevant because spices and herbs are inexpensive, easily available, and can be added easily to everyday meals. The authors noted that the work was funded in part by the McCormick Science Institute, with relevant advisory relationships disclosed.

Researchers concluded that long-term studies involving diverse populations are still needed to identify optimal spice combinations and therapeutic doses.

Download your PDF copy by clicking here.