Considerations on an Approach for Establishing a Framework for Bioactive Food Components

Abstract

Bioactive food components have shown potential health benefits for more than a decade. Currently there are no recommended levels of intake [i.e., Dietary Reference Intakes (DRIs)] as there are for nutrients and fiber. DRIs for essential nutrients were based on requirements for each specific nutrient to maintain normal physiologic or biochemical function and to prevent signs of deficiency and adverse clinical effects. They were later expanded to include criteria for reducing the risk of chronic degenerative diseases for some nutrients. There are many challenges for establishing recommendations for intakes of nonessential food components. Although some nonessential food components have shown health benefits and are safe, validated biomarkers of disease risk reduction are lacking for many. Biomarkers of intake (exposure) are limited in number, especially because the bioactive compounds responsible for beneficial effects have not yet been identified or are unknown. Furthermore, given this lack of characterization of composition in a variety of foods, it is difficult to ascertain intakes of nonessential food components, especially with the use of food-frequency questionnaires designed for estimating intakes of nutrients. Various intermediary markers that may predict disease outcome have been used as functional criteria in the DRI process. However, few validated surrogate endpoints of chronic disease risk exist. Nonvalidated intermediary biomarkers of risk may possibly predict clinical outcomes, but more research is needed to confirm the associations between cause and effect. One criterion for establishing acceptable intermediary outcome indicators may be the maintenance of normal physiologic function throughout adulthood, which presumably would lead to reduced chronic disease risk. Multiple biomarkers of outcomes that demonstrate the same health benefit may also be helpful. It would be beneficial to continue to refine the process of setting DRIs by convening a workshop on establishing a framework for nonessential food components that would take into consideration intermediary biomarkers indicative of optimal health.

Is cytotoxicity a determinant of the different in vitro and in vivo effects of bioactives?

“…Although food bioactives have shown potential health benefits, currently there are no specific recommended intakes (i.e., Dietary Reference Intakes, DRIs) for the most of them. DRIs are based on requirements for the specific nutrient to maintain normal physiologic or biochemical function, and to prevent signs of deficiency and adverse clinical effects; for some nutrients, they have been expanded to include criteria for reducing the risk of chronic degenerative diseases [ 3 ]. The evaluation of the beneficial properties, the effective dose and the safety of bioactives are essential for establishing the corresponding DRIs, and this represents a big challenge to many scientists.…”

Characteristics and Health Benefits of Phytochemicals

“…An appropriate framework is still needed for establishing their recommended intakes, because their recognized health benefits may not be readily defined in the context of nutritional essentiality [3]. It would be helpful to establish this framework for these nonessential food components that would take into consideration intermediary biomarkers indicative of optimal health [4]. …”

Twenty Years of the Dietary Supplement Health and Education Act—How Should Dietary Supplements Be Regulated? ,

“…The nutrition science community has become accustomed to large randomized, controlled trials having the greatest weight in establishing a causal relation between a particular food or food component and a disease outcome. This approach works well when studying deficiency-related disorders; however, it may not be as useful when measuring long-term health maintenance because most clinical interventions have limitations, including length (duration too short), confounding, multicollinearity introduced by other nutrients in the diet that interact with the constituent of interest, and subject compliance, and because all individuals are expected to have some type of baseline status and/or already be sufficient (15,16).…”