Patent ID: 8512676

Claim:
A method of determining if an individual is transitioning from a healthy state to an unhealthy state, the method comprising: monitoring breath taken from the individual and measuring a relative amount of a first isotope to a second isotope therein over a total time interval (t total ), wherein the individual is healthy during the time interval t 0-healthy , wherein t 0 is a time point at the start of time interval t total , and t healthy is time point during t total in which the individual is healthy, identifying a healthy functional oscillation pattern in the relative amount of the first isotope to the second isotope therein during time interval t 0-healthy , identifying a test functional oscillation pattern in the relative amount of the first isotope to the second isotope therein a test time interval t test within t total , wherein t test does not overlap t 0-healthy , and determining that the individual is transitioning from a healthy state to an unhealthy state when the healthy functional oscillation pattern and the test functional oscillation pattern are distinct in period of oscillation, oscillations per unit time, and/or variability in oscillation period, wherein the first and second isotopes are selected from the group consisting of a pair of 13 C and 12 C, a pair of 15 N and 14 N, a pair of 17 O and 16 O, and a pair of sulphur isotopes.