Nutrition dose-response relationships

Another difference from drug therapy is that the dosing interval of a nutritional supplement is often not a critical parameter for a positive outcome. This lack of a strong dose-response relationship is an important consideration in setting of standards for dietary supplements and is in stark contrast to the situation for drug products. 

Prentice AM and Bates CJ (1981b) A biochemical evaluation of the erythrocyte glutathione reductase (EC 1.6.4.2) test for riboflavin status. 2. Dose-response relationships in chronic marginal deficiency. British Journal of Nutrition 45,53-65. 

Lands WEM. Dose-response relationships for 3/ 6 effects. In Simoupoulos AP et al., eds. Health Effects of 3 Polyunsaturated Fatty Acids in Seafoods. World Review of Nutrition and Dietetics, Vol. 66, pp.177-194. Karger, Basel, 1991. 

Additionally, more recently, some scientists have also suggested that even when compounds exhibit nonlinearity on the cellular level, they are likely to manifest as a linear dose-response relationship on the population level. This hypothesis, as presented by White et al. (2009), holds that modifying factors (such as nutritional status) and biological variability cause the dose-response relationship to be linear across the population (White et al. 2009). 

The relative binding response is interpolated from a calibration curve in order to compute concentration. As an inhibition assay, the response is inversely related to biotin concentration and exhibits a sigmoidal dose-response relationship that is typical of most ligand-binding assays. With respect to specificity, the routine compliance assay is targeted to the quantitation of free biotin only in nutritional dairy products, and therefore does not include biocytin (Indyk et al. 2000). However, in milk and supplemented infant formulas, the overwhelming majority of biotin is present in the free form. 

In contrast, in 8083 women of childbearing potential in the 2005-2006 US National Health and Nutrition Examination Survey, higher serum folate concentrations were associated with a lower risk of high total serum IgE concentrations, atopy, and wheezing [32 ]. There was a dose-response relationship between higher serum folate concentrations and lower risks of these outcomes, and the associations were independent of age, sex, race/ethnicity, and poverty. 

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