Spicy is in. Not merely as a way to tickle the palate or define an ethnic cuisine, or even to preserve food (an original motivation for spicing). Increasingly, we are learning that the instinct to "kick it up a notch" is a healthy one. But first things first: What exactly is a spice?
Traditionally, spices are defined as the dried seeds, fruits, roots, pieces of bark or other vegetable substances used in nutritionally insignificant quantities to flavor and preserve food and to prevent the growth of pathogenic bacteria. They are distinguished from herbs, which are leafy green plant parts used for flavoring, and from salt, which is a mineral.
Humans have a historic relationship with spice that can be traced to the Indian subcontinent and Southeast Asia. We find mention of spice traders in the book of Genesis, the Song of Solomon and the Hindu epic of Ramayana. By about 4,000 years ago, the trade of cinnamon and pepper burgeoned throughout the Middle East.
During the Middle Ages, spices such as ginger, cloves, cinnamon, nutmeg, cardamom and peppers of all varieties were considered luxurious commodities. And when Venice demanded too much money for spices, Vasco de Gamma sailed to India to open spice routes for Spain and Portugal. Even Christopher Columbus got his investors excited about the prospect of spices from the New World - which he "discovered" while looking for a new spice route to India.
Back then, we spiced for taste, food preservation (many spices possess antimicrobial effects stronger than pharmaceutical antibiotics) and medicinal value (which was steeped in tradition). Today, there are additional motivational forces driving us to continue the spice trade. They include a wealth of studies showing how spices weigh in on the major health concerns of the day. In fact, the health potential of spices is so great some spice companies are sponsoring their own research programs.
"Many spices are known for their antioxidant properties, especially in the test tube," says Guy Johnson, executive director of the McCormick Scientific Institute. The institute, a separate entity from McCormick & Co. (www.mccormickflavor.com), Hunt Valley, Md., both sponsors research and communicates the benefits of herbs and spices to the public. "We are interested in the practical application of that health potential. What are the specific compounds? What is their bioavailability? What is the effect of processing? Do different spices act synergistically to increase the antioxidant effect?"
Spicing up health
A study reported last summer in the British Journal of Nutrition showed regular consumption of chili pepper (30g/day; 55 percent cayenne) increased the resistance of serum lipoproteins to oxidation in healthy human volunteers. This confirmed in vitro studies showing extracts of capsaicin (the active ingredient in peppers) protect LDL cholesterol and linoleic acid (an omega-6 fatty acid) form oxidation. Oxidized LDLs are a major risk factor in cardiovascular disease.
Another area of ongoing research into the benefits of spice concerns inflammation. "Inflammation is one of the early negative occurrences of the disease state," says Johnson. "If inflammation can be controlled, many conditions - such as cancer, heart disease and others - can be positively affected."
In "Spicing Up of the Immune System by Curcumin," published in December in the Journal of Clinical Immunology, Drs. Ganesh Jagetia and Bharat Aggarwal at the Cytokine Research Laboratory of The University of Texas M. D. Anderson Cancer Center, Houston, reviewed the research on curcumin, the orange-yellow component of the traditional spice turmeric. Turmeric is often prescribed in traditional Ayurvedic medicine as an anti-inflammatory agent.
Research over the past two decades shows curcumin to be a potent modulator of the immune system, affecting the activation of T cells, B cells, macrophages, neutrophils, natural killer cells and dendritic cells. Curcumin also can slow the production of various pro-inflammatory chemicals collectively known as cytokines and chemokines.
Researchers believe curcumin accomplishes all this by inactivating a protein called transcription factor NF-ĸB, responsible for an abnormal inflammatory response. It's the abnormal inflammatory response that increases the risk of diseases such as cancer, arthritis, allergies, asthma, atherosclerosis, heart disease, Alzheimer's disease and diabetes.
"I'm excited about the research that links modern science to ancient Ayurvedic medicine," says Winston Boyd, technical director and business development manager for Food Ingredient Solutions LLC (www.foodcolor.com), Teterboro, N.J. Boyd has studied antioxidants and other healthful properties of spices for more than 30 years.
A 2003 study reported in Diabetes Care demonstrated cinnamon lowers fasting serum glucose, triglycerides (blood fats), LDL and total cholesterol in patients with type-2 diabetes. More recently, a study, at the University of Lund, Sweden, and published in the January American Journal of Clinical Nutrition, showed healthy subjects eating rice pudding spiked with only 6g of cinnamon reduced both after-meal blood sugar and gastric emptying (the rate at which food leaves the stomach). Moreover, gastric emptying could account for only part of the cinnamon effect on blood sugar.