From the 1H NMR perspective, the human body is composed primarily of fat hydrogens (-CH2-) and water hydrogens (H2O). The resonance frequency difference between the NMR signal from these two types of hydrogens is approximately 220 Hz on a 1.5 Tesla imager. What is the chemical shift difference?

d = (n - nref) x 106 / nref

nref = gBo

d = (n - nref) x 106 / gBo

where:

    nref = resonance frequency
    g = gymagnetic ratio for the nuclei in question
    Bo = magnetic field strength
    n = resonance frequency of second component
    d = chemical shift difference

Given:
    B0 = 1.5 T
    n - nref = 220 Hz
    gBo = 42.58 MHz/T * 1.5 T = 63.87 MHz

d = 220 Hz / 63.87 MHz * 106 = 3.444 = chemical shift difference