Biomarkers for nutrient intake with focus on alternative sampling techniques

Abstract

Biomarkers of nutrient intake or nutrient status are important objective measures of foods/nutrients as one of the most important environmental factors people are exposed to. It is very difficult to obtain accurate data on individual food intake, and there is a large variation of nutrient composition of foods consumed in a population. Thus, it is difficult to obtain precise measures of exposure to different nutrients and thereby be able to understand the relationship between diet, health, and disease. This is the background for investing considerable resources in studying biomarkers of nutrients believed to be important in our foods. Modern technology with high sensitivity and specificity concerning many nutrient biomarkers has allowed an interesting development with analyses of very small amounts of blood or tissue material. In combination with non-professional collection of blood by finger-pricking and collection on filters or sticks, this may make collection of samples and analyses of biomarkers much more available for scientists as well as health professionals and even lay people in particular in relation to the marked trend of self-monitoring of body functions linked to mobile phone technology. Assuming standard operating procedures are used for collection, drying, transport, extraction, and analysis of samples, it turns out that many analytes of nutritional interest can be measured like metabolites, drugs, lipids, vitamins, minerals, and many types of peptides and proteins. The advantage of this alternative sampling technology is that non-professionals can collect, dry, and mail the samples; the samples can often be stored under room temperature in a dry atmosphere, requiring small amounts of blood. Another promising area is the potential relation between the microbiome and biomarkers that may be measured in feces as well as in blood.

Biomarker of food intake for assessing the consumption of dairy and egg products

“…Finally, Burton et al [ 118 ] reported an increased in faecal Bifidobacteria after consumption during 2 weeks of a non-fermented milk acidified with D-(+)-glucono-δ-lactone but not after the consumption of yoghurt. In this field, it is, however, important to keep in mind that there are different methods and no standard protocols for assessing bacterial proportions in faecal samples [ 123 ].…”

“…Although the compounds mentioned in this section have been linked to yogurt consumption, none of them qualify as a biomarker of yogurt intake; these metabolites are widely distributed in several food sources, compromising their specificity with respect to yogurt intake. These compounds can more likely be used as biomarkers of nutrient intake, nutritional status or microbiota integrity than as biomarkers of specific food consumption, as recently reviewed by Holen and co-workers [ 123 ].…”

Prevalence of protein intake below recommended in community‐dwelling older adults: a meta‐analysis across cohorts from the PROMISS consortium

“…52,53 To improve the estimation of protein intake, studies including data on biomarkers of energy and protein intake, for example 24 h urine nitrogen, are recommended. 19,44,54,55 Implications for clinical practice…”

Comparing identified and statistically significant lipids and polar metabolites in 15‐year old serum and dried blood spot samples for longitudinal studies

“…DBS offer a simpler way of storing and acquiring blood samples and have been used for disease surveillance, drug resistance analyses, clinical and pre‐clinical pharmacokinetic studies, population studies, and global newborn screening of metabolic diseases since the 1960s . DBS samples have many benefits compared to standard serum and plasma samples in that collection is less invasive for the patient (normally a finger or heel prick), storage and transport costs are lower, and sampling does not require a health personnel so it can be performed anywhere . These benefits are of particular interest for studies in remote locations and those having large cohorts where thousands of samples are collected and must be stored.…”