Spices and herbs contain chemical compounds named polyphenols and flavonoids. Polyphenols and flavonoids are found in foods especially in fruits, vegetables, teas, and spices. Polyphenols are widely known for their antioxidant properties however they exert other biological effects. These benefits include their possible role in conferring protection against cardiovascular and neurodegenerative diseases, cardiovascular disease, cancer and type 2 diabetes.
Spices and herbs such as clove, rosemary, sage, oregano, and cinnamon are excellent sources of antioxidants providing high content of polyphenols.. Rosemary, sage and thyme (uncooked, cooked and digested) even in amounts used for food preparing and cooking, suggest significant benefits of rosmarinic acid which increases antioxidant capacity following cooking. Sage and thyme elicited an anti-inflammatory effect via the inhibition of, and also protection against, the action of pro-inflammatory agents, hydrogen peroxide (H2O2) and tumor necrosis factor α (TNFα).
Cinnamon, clove and nutmeg (uncooked, cooked and digested) significantly inhibited the pro-inflammatory COX-2 enzyme, which is the same enzyme that NSAIDS block. The anti-COX-2 activity was shown to be only partially related to the antioxidant capacities and polyphenolic properties of these spices. This suggest there are more benefits beyond those only found in the polyphenols this post talks about. Cinnamaldehyde, for example, is a component of cinnamon and also found in the essential oil which is responsible for its aroma and flavor has also been shown to inhibit COX-2.
There are numerous benefits and examples different herbs providing their own individual benefits. Many of these compounds have proven to be antioxidative, anti-inflammatory, antitumourigenic, anticarcinogenic, and possess glucose lowering and cholesterol lowering capabilities. There is also a growing amount of literature explaining how polyphenols provide health benefits via their action on gut microbiome which, in humans, are related to risks of diabetes, cardiovascular disease, liver disease and other inflammatory conditions.
Of special interest to me, some of these compounds have been shown to contain properties that affect cognition and mood, which have been shown to be beneficial in clinical and therapeutic trials. In a study examining salt intake and blood pressure of those who dislike spiciness showed that those who enjoy spicy flavors had an increase in salt sensitivity and reduced intake of salt. This was directly related to the metabolic activity in the insulation and orbitofrontal cortex. A study showed that capsaicin modulated the metabolism in the aforementioned brain regions.
A recent observational study assessed consumption of spicy foods as part of a daily diet and the total risk and causes of death in 487,375 participants, aged 30–79 years, during a median follow-up of 7.2 years in China. Those who ate spicy foods 1 or 2 days a week were at a 10% reduced risk of death. Those who ate spicy foods three to five and six to seven days a week were at a 14% reduced risk of death.
13 randomized control trial investigating 750 participants showed that those who supplemented cinnamon significantly reduced blood triglycerides and total cholesterol . It was also shown that short term cinnamon intake resulted in reductions of systolic and diastolic blood pressure. Recent studies have shown that intake of 3g/day in both healthy and diabetic subjects improved glucose control and insulin sensitivity.
Ginger has been shown to decrease inflammation by working on PGE2 and NF-kB. These are markers which have been shown to influence pain and other lifestyle conditions. In a study done on subjects with osteoarthritis, 500mg of ginger capsules have daily over 3 months significantly reduced inflammatory markers (TNFa and IL-1b). Ginger also decreased COX-1 protein expression at those high risk for colorectal cancer.
Intake of 2g over 11 days of raw or heat treated ginger was shown to reduce muscular pain and inflammation and improve muscular function and strength in 20 non weight trained individuals.
Tumeric has been shown to decrease lipid peroxidation and LDLs. It also was shown to reduce DNA damage (oxidative stress). Tumeric has been shown to decrease serum levels of pro inflammatory markers in 59 subjects with metabolic syndrome. These subjects were taking 1g/day for 8 weeks.
A study investigating 10 adults showed at 500mg of cur cumin a day for 7 days had a 12% reduction in total cholesterol and 29% improvement in HDL-C levels. It has also been shown to reduce cholesterol in acute coronary syndrome with various dosages.
Tumeric intake has been shown to improve A-Beta plaque clearance and reduce aggregation A-Beta plaques are compound which is linked to neuro-degenerative conditions. Intake has also been shown to decrease brain blood vessel spasm which could cause headaches or be secondary to brain damage.
A study on 1000 people aged 60-93 showed that regular turmeric intake assisted in preserving cognitive function. Turmeric has also been shown to be anti-depressive in a study of those taking 1 gram daily.
Rosemary has been shown to decrease pro inflammatory markers (NF-kB and IL-1b) and also serves as an antioxidant by reducing cellular membrane damage and decreasing lipid peroxidation.
The aroma of rosemary (plant or essential oil) was shown to improve cognitive function in a randomized control trial in 140 subjects. It also decreased test-taking stress in graduate students. Rosemary has an interaction with the monoamingeric system which may promote brain health by facilitating communication among brain cells.
In a clinical trial with 1g of garlic intake daily for 12 weeks showed significant improvements in joint stiffness, pain, and physical activity in overweight and obese women with osteoarthritis.
Garlic can also promote cardiovascular health by preventing atherosclerosis. This can prevent stroke or heart attacks. Garlic also stimulates nitric oxide and inhibits ACE activity which results in a blood pressure lowering mechanism.
There are so many benefits of herbs and spices, including the ones mentioned here, that cannot be captured in one single post. The combination and experimentation of all these herbs in different dishes, or supplementation can provide countless benefits in all sorts of conditions, or promotion of health.