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?

δ = (ν - νref) x 106 / νref

νref = γBo

δ = (ν - νref) x 106 / γBo

where:

    νref = resonance frequency
    γ = gymagnetic ratio for the nuclei in question
    Bo = magnetic field strength
    ν = resonance frequency of second component
    δ = chemical shift difference

Given:
    Bo = 1.5 T
    ν - νref = 220 Hz
    γBo = 42.58 MHz/T * 1.5 T = 63.87 MHz

δ NT>= 220 Hz / 63.87 MHz * 106 = 3.444 = chemical shift difference