REVISITING SILICA: AN EMERGING BIOACTIVE NUTRIENT IN FOOD, HEALTH, AND MEDICINE (si(OH)4)

Silica (silicon dioxide) is a naturally abundant mineral found on earth. During the last decade, silica has received a lot of attention due to its newly proposed potential health benefits. To date, silica is an important bioactive dietary component that plays a critical role in its bioavailability and in maintaining human health in relation to skeletal and connective tissue health. Recent studies related to silica as a dietary component include bioavailability and analysis of silica within the body, nutrigenomics, biomedical technology, effects on bone health, potential cosmetic applications, and relationship with probiotics. In this review, silica will be defined, from where it came about, what it is composed of, and where it can be found. Special attention will be focused on silica-rich sands that are found throughout the world. Dietary silica and naturally occurring silica in plant-based foods, beverages, and functional products will be discussed. Topics including absorption, metabolism, biological roles of silica within the human body, and interactions with calcium and trace minerals will be reviewed. Special attention will be discussed on silica’s possible mechanisms of action that aid in bone mineralization and prevention of osteoporosis. Reviews will include silica enhanced products, probiotic–silica relationships, nutrigenomics, and how silica relates to aeronutrition. Research on cosmetic uses of silica, new medical technologies utilizing silica, and functional food applications will be reviewed. Market values and cost will also be discussed. Lastly, needs and opportunities for future research will be discussed to help aid silica as a nutraceutical and in biomedical applications.