Foods, phenolic acids health effects

The impact of plant products on the metabolism of synthetic dmgs results from the inhibition or activation of cytochrome P-450 (CYP) enzymes. Evaluation of the potential activation of CYP by administration of natural plant products or dietary supplements is important for prediction of interactions between their components and dmgs. Therefore, attention is directed to research on the impact of products available on the food market known as natural non-nutritive substances on dmg absorption. Non-nutritive dietary components are mainly secondary plant metabolites, which include, among others, phenolic compounds such as phenolic acids and flavonoids. The health effects of non-nutritive substances are not yet known. So far, there is no answer on the extent to which they are absorbed and metabolized by the body, and there is no information on the permitted daily intake for these compounds. This information is particularly important because certain non-nutritive natural substances are simultaneously considered to be anti-nutritional factors, mainly because they inhibit digestion and reduce the bioavailability of nutrients or dmgs. It is also possible that they form undesirable interactions with dmgs. The positive health effects of non-nutritive natural substances are not only attributed to their antioxidant properties. These substances are involved in various metabolic... 

Observations of lower rates of certain chronic diseases in several Asian countries compared to the United States served as the impetus for studies that were conducted to identify the factors that were accountable (Tham et al., 1998). Consumption of soy is one factor that correlated with these lower rates. From this information, much research focused on soy protein and accompanying bioactive compounds with regard to elucidating mechanisms associated with risk markers for chronic disease, particularly CVD. The combination of macro- (protein, fiber, fat) and micro-components (isoflavones, saponins, tocopherols) as part of many traditional soy foods may underlie the epidemiological observations associated with soy intake. A body of cell culture and animal data shows potential health effects of a multitude of bioactive components in soy (i.e., saponins, phenolic acids, peptides). However, studies determining the independent effects of saponins, phenolic acids, and protease inhibitors in humans are yet to be conducted. 

Almond is a nutrition-dense food providing a spectrum of macro- and micronutrients. Moreover, it is an excellent source of bioavailable phytochemicals that are believed to possess health promotion potentials. Among these phenolic compounds, including phenolic acids and flavonoids, which are the major antioxidant active substances in almond. Other components such as tocopherols and terpenoids also make contribution to the antioxidant activity of almond. The health benefits of almond have been explored. Almond appears to be effective in reducing the risk of heart disease and cancer prevention, and consumption of ahnond is reconunended by FDA for better health conditions. 

The literature provides information that correlates a diet rich in phenolic acids with the maintenance of health and disease prevention. The high antioxidant contents in fruits and vegetables inhibit oxidative damage diseases such as coronary heart disease, stroke, and cancers [40-42]. Certain foods are even classified as functional foods, owing to their established protective effects on human health. 

Oxidative cellular damage by reactive oxygen species such as superoxide anion, hydroperoxy and hyassociated with various human chronic diseases, e.g. cancers, inflammation, arthritis, atherosclerosis and also with the process of ageing. Claims that diet and increased intake of nutrients exhibiting antioxidative activity have a preventative effect on chronic diseases have increased in recent years. In this context, polyphenolic compounds such as tannins, flavonoids, coumarins, lignans and caffeic acid derivatives, which are abundantly contained in a large number of medicinal plants, foods and beverages, are of particular interest for human health care because of the antioxidative properties widely found in plant phenolics. The antioxidative activity of tannins has been extensively studied in various in vitro and in vivo experimental systems and summarized in reviews [96, 97]. Such activity includes the inhibition of lipid peroxidation induced by NADPH-ADP and ascorbic acid-ADP in rat liver microsomes and mitochondria, respectively... 

Naim M, Zehavi U, Nagy S, Rouseff" RL. Hydroxycinnamic acids as off-flavor precursors in Citrus fruits and their products. In Ho CT, Lee CY, Huang MT, eds. Series 506 Phenolic Compounds in Food and Their Effects on Health I. Analysis, Occurrence, and Chenustry. Washington, DC ACS, 1992 180 191. 

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