Diet-disease relationships need "more-illuminating" biomarkers: IFT
There are many biomarkers pertinent to diet and disease, Roger Clemens and Peter Pressman explain in the January issue of Food Technology . All biomarkers should
"indicate the biological plausibility of a diet-disease relationship, improve the assessment of relative risk, and serve as surrogate endpoints,"
the authors explain. Biomarkers include blood pressure, serum glucose, serum triglycerides. Some are better indicators than others. There is a "critical need for markers that distinguish the clinically meaningful stages of … pathology," they state, decrying the "simplistic model" that fails to predict outcomes accurately. They warn:
"The food industry, in its effort to provide more-healthful choices in the functional foods arena, must consider more-illuminating biomarkers that punctuate the much larger and exquisitely complex constellations o factors representing our emerging knowledge of the progression of disease states.
"As we examine the mechanisms of disease progression and the role of diet in augmenting health, it becomes paramount that we realize fundamental processes. …
"… our task will be ideally to select a biomarker that serves both as intervention target and as "barometer" of intervention efficacy and health status or of disease progression. …
"… we are engaging a clear priority on health promotion and disease risk reduction.
"Along with this movement is the absolute ethical and legal requirement that we scientifically support any health claims …."
Thus, the choice of a marker is key and, they add,
"when specifying a biomarker, it is important to understand how it fits with nutritional exposure or intake, time frame, sampling, specimen collection, storage, the model system under study…, biologic variation, and the analytic quality control."
Unmentioned by Clemens and Pressman is the growing awareness of the inadequacy of blood pressure as a reliable biomarker for cardiovascular risk. Increasingly, we understand that not only are multiple processes and interactions taking place with regard to dietary sodium intake and that individuals vary widely in their response, but that how we attempt to change surrogate biomarkers can be a clear indicator of the result. We need to focus on the hard disease outcomes and then look back to see which surrogate biomarkers offer value predicting adverse outcomes. Until then, take two doses of humility and see me in the morning.
