Electronic Noses for Well-Being: Breath Analysis and Energy Expenditure

Abstract

The wealth of information concealed in a single human breath has been of interest for many years, promising not only disease detection, but also the monitoring of our general well-being. Recent developments in the fields of nano-sensor arrays and MEMS have enabled once bulky artificial olfactory sensor systems, or so-called "electronic noses", to become smaller, lower power and portable devices. At the same time, wearable health monitoring devices are now available, although reliable breath sensing equipment is somewhat missing from the market of physical, rather than chemical sensor gadgets. In this article, we report on the unprecedented rise in healthcare problems caused by an increasingly overweight population. We first review recently-developed electronic noses for the detection of diseases by the analysis of basic volatile organic compounds (VOCs). Then, we discuss the primary cause of obesity from over eating and the high calorific content of food. We present the need to measure our individual energy expenditure from our exhaled breath. Finally, we consider the future for handheld or wearable devices to measure energy expenditure; and the potential of these devices to revolutionize healthcare, both at home and in hospitals.

Keywords: VOC; breath analysis; energy expenditure; well-being.

Figure 1

Components of EE [100].

Figure 2

EE and physical activity measured under conditions of two and three meals per day. Arrows indicate meal times. Adapted from [107].

Figure 3

(a) Total daily EE increased after a single bout of SIT. Closed and open circles indicate individual responses and the group mean, respectively; (b) mean EE found from the group during a sedentary day compared to a day with the SIT period. Adapted from [112].