The term "nutraceuticals" is a portmanteau of the words nutrition and pharmaceutical. Though coined by Dr. Stephen DeFelice in 1989, the idea can be traced back to Hippocrates. Natural herbs and spices have been used as folk medicine for centuries throughout Asia. Ancient Indians, Chinese, Egyptians and Sumerians used long ago what we would today call nutraceuticals. These creations have many therapeutic benefits, such as fighting fatigue and the prevention or delay of age-related ailments -- arthritis, cancer, metabolic syndrome, cardiovascular problems, Alzheimer's disease, Huntington's disease, osteoporosis, cataracts, brain disorders and many others.
The International Food Information Council has defined foods that have health benefits beyond basic nutrition as "functional foods." These can range from broccoli to fortified foods such as calcium- and vitamin C-added orange juice, soy-based products and dietary supplements.
Nutraceuticals range from isolated nutrients, dietary supplements and specific diets to genetically engineered designer and processed foods, herbal products, cereals, soups and beverages. They also include bioengineered designer vegetable food -- rich in antioxidants -- supplied as fortified foods, capsules, tablets or powder. The use of nutraceuticals has grown recently as they contain antioxidants and phytochemicals, which are beneficial to overall health.
Nutraceuticals can provide numerous health benefits, such as helping to decrease body fat, increase stamina and lower blood-glucose levels and cholesterol. Phytochemicals give color to fruits and vegetables and provide benefits due to their powerful components. The bitterness, spiciness and pungency created by phytochemicals provide taste, aroma and texture. When combined with powerful antioxidants, they prevent damage to the cell walls to avoid or postpone the onset of chronic diseases and to reduce aging.
Our breakfast cereals are fortified with vitamins and iron -- vitamin C is enriched with folic acid to help pregnant women to prevent neural tube birth defects, such as spina bifida. Margarines that contain plant sterols can lower bad cholesterol. Polyunsaturated fatty acids and fish oils have blood-thinning properties -- similar to warfarin. Carotenoids are lipids that include beta-Carotene, which has vitamin A, a deficiency of which can lead to blindness. Lutein, found in green leafy vegetables, prevents age-related degeneration and helps keep eyes in good health.
The advent of nanotechnology used in pharmaceutical applications has opened new avenues for stability, solubility and permeability enhancement of problematic nutraceuticals. Researchers are seeking nanodelivery methods through biopolymers such as proteins and polysaccharides. For example, nanocapsules prepared from protein and oligosaccharide conjugate when encapsulated with hydrophobic nutraceutical, such as vitamin D, which is then protected from stomach acid and subsequently released in the small intestine, where enzymes can break up the saccharide-protein structure. Another benefit is polymer coating for capsules, which protects vitamin D during refrigeration before consumption.
Another category of nutraceuticals is probiotics -- or health-promoting bacteria. Their oral delivery is hampered by the low instability of bacteria in the gastro-intestinal track. For delivering living probiotic cells, bacteria are immobilized into a polymer matrix that remains intact while in the stomach and dissolves in the intestine.
There is also heat-treated beta-lactoglobulin (milk protein) that can entrap and protect green tea epigallocatechin gallate (EGCG) -- which is linked to the prevention of neurodegenerative diseases, cardiovascular ailments and cancer -- from degradation in clear drinks. The capsule can suppress EGCG's bitterness that limits its addition to beverages. Currently, scientists are studying the interaction of these nanodelivery systems in the human digestive tract to facilitate high bioavailability and protection of the bioactive compounds during digestion.
The majority of nutraceuticals are taken orally. Though there are concerns about their formulation, bioavailability and site-specific delivery. Indeed, due to their unstable nature, oral absorption and targetability are the major impediments for getting the most out of ingesting nutraceuticals. Researchers are developing methods to improve this, such as with nanotechnology. Already, promising results are being seen through greater protection and stability on shelves and in use, solubility enhancement, intestinal permeability, intracellular targeting and extended circulation half-life.
Nutraceuticals are growing in notoriety as consumer awareness grows regarding health and fitness. It is expected to grow further because of lifestyle changes in emerging markets such as in the Middle East, Asia-Pacific and Latin America. Even the beauty industry is becoming a major growth driver for nutraceuticals.
Many nutraceutical products are on shelves already -- mostly antioxidants and probiotics. But not many nanodelivery systems have been commercialized yet. There are some, however. For instance, nanosized self-assembled liquid carriers developed by NutraLease is available in Israel for nutraceuticals in food products. In these liquid structures, hydrophobic nutraceuticals -- coenzyme Q-10, vitamins A, D and E and omega-3 fatty acids -- are made soluble. These fatty acids are formulated into nanodelivery systems by BioDelivery Sciences International, a U.S. company, as well as by Aquanova, a German liquid formula company.
Europe, the U.S. and Japan dominate the functional food market, with a combined share of 85%. By 2015, the U.S. market might reach $90 billion, while the global market reaches about $243 billion. In the Asia-Pacific, Japan is the largest consumer, followed by China. In India, the nutraceutical market could potentially see moderate growth contributing around 71% of the dietary supplement market.
Tejraj M. Aminabhavi is Emeritus Professor and Research Director, Soniya College of Pharmacy, Dharwad, India