Introduction: "Onions sting the nose, garlic the heart, and chili peppers the lips." This vivid proverb tells us that the human body experiences different sensations after consuming various spicy foods. While the sensation of "spiciness" is the same, the substances that cause it in different foods are not, and thus their health benefits also differ slightly.
The spicy component of allium vegetables like onions and scallions is organic sulfur compounds, which are volatile and can irritate the nose and eyes. This is also why people often "tear up" when cutting onions. Organic sulfur compounds are water-soluble, so dipping the knife in water while cutting can reduce the "tearing" effect. Studies have shown that organic sulfur compounds have antibacterial, anticancer, and anti-inflammatory properties, and can also scavenge free radicals in the body, providing antioxidant effects. Cutting onions and scallions and leaving them in the air for too long, or cooking methods like high-heat frying, can reduce the content of organic sulfur compounds. Therefore, the best way to eat allium vegetables is raw or briefly stir-fried.
Allicin is the main source of spiciness in garlic. It is usually stored in garlic cloves in the form of alliin and only forms allicin, which irritates the gastrointestinal tract, after being crushed under the action of the alliinase enzyme. Therefore, it's best not to eat raw garlic on an empty stomach, as it can easily damage the gastric mucosa. Allicin can promote the human body's absorption of vitamin B1 and has functions such as sterilization, lowering blood lipids, and anticancer effects. Allicin is also deactivated by heat, so it's best to eat garlic raw, and preferably crush it into a paste and let it sit for 10-15 minutes before eating, which is more conducive to the formation of allicin.
The main spicy substance in chili peppers is capsaicin. It stimulates the oral mucosa and the trigeminal nerve, causing a burning pain sensation. Sweetness can mask and interfere with the spiciness, acidity can neutralize the alkaline capsaicin, and the casein in milk can bind with capsaicin. Therefore, when you're feeling the burn, a little vinegar, a bowl of iced sweet drink, or a glass of milk can be very helpful. Capsaicin can help the body resist cold and dampness, and may also help reduce the risk of heart disease and atherosclerosis. Chili peppers are best cooked, as raw chili peppers contain a large amount of capsaicin, which can irritate the oral and gastrointestinal mucosa. After heating, the irritation to the gastrointestinal tract is reduced.
The spiciness of ginger is persistent, constant, yet mild, which is mainly related to gingerol. Gingerol has a very high boiling point, up to 240°C, so its spiciness remains even after being fried, stir-fried, or deep-fried. Gingerol can also enhance blood circulation, stimulate gastric juice secretion, and excite the intestines, promoting digestion, strengthening the stomach, and increasing appetite. Ginger can be prepared in various ways, and everyone can choose according to their own taste. It should be noted that rotten ginger produces safrole, which can easily cause poisoning and degeneration of liver cells, so rotten ginger must be discarded.
When black and white mustard sinigrin in wasabi are hydrolyzed, they produce a volatile spicy substance—allyl isothiocyanate—which has a strong irritating effect on the nose. Therefore, it's best not to eat wasabi alone; it can be eaten with dumpling vinegar or soy sauce for sushi. Research shows that washib can inhibit the activity of cancer-causing substances. A study from the University of Illinois suggests that eating broccoli with wasabi can enhance its anti-cancer effects.