This review compares key isothiocyanates—phenethyl isothiocyanate (PEITC), sulforaphane (SFN), and Moringa isothiocyanates (MIC)—and their health benefits. Isothiocyanates are bioactive compounds derived from glucosinolates in cruciferous vegetables, with diverse biological activities including anticancer, anti-inflammatory, and antioxidant properties. PEITC, derived from watercress, activates Nrf2 and exhibits neuro- and cardioprotective effects, as well as antitumor and antimutagenic properties. SFN, derived from broccoli, is a well-studied isothiocyanate with anticancer, anti-inflammatory, and cardioprotective effects, and it induces apoptosis in tumor cells. MIC, derived from Moringa oleifera, are less studied but show similar health benefits, including anti-inflammatory and antioxidant effects. The metabolism of these compounds involves conjugation with glutathione and excretion via the kidneys. Nrf2 activation is a key mechanism for their antioxidant and anti-inflammatory effects. All three isothiocyanates activate Nrf2, leading to the expression of antioxidant enzymes and protection against oxidative stress. PEITC and SFN have been shown to inhibit cancer growth and progression, while MIC also exhibit antitumor activity. Additionally, these compounds have neuroprotective effects, reducing oxidative stress and inflammation in the brain. The review highlights the potential of isothiocyanates as chemopreventive agents and their role in various health benefits.This review compares key isothiocyanates—phenethyl isothiocyanate (PEITC), sulforaphane (SFN), and Moringa isothiocyanates (MIC)—and their health benefits. Isothiocyanates are bioactive compounds derived from glucosinolates in cruciferous vegetables, with diverse biological activities including anticancer, anti-inflammatory, and antioxidant properties. PEITC, derived from watercress, activates Nrf2 and exhibits neuro- and cardioprotective effects, as well as antitumor and antimutagenic properties. SFN, derived from broccoli, is a well-studied isothiocyanate with anticancer, anti-inflammatory, and cardioprotective effects, and it induces apoptosis in tumor cells. MIC, derived from Moringa oleifera, are less studied but show similar health benefits, including anti-inflammatory and antioxidant effects. The metabolism of these compounds involves conjugation with glutathione and excretion via the kidneys. Nrf2 activation is a key mechanism for their antioxidant and anti-inflammatory effects. All three isothiocyanates activate Nrf2, leading to the expression of antioxidant enzymes and protection against oxidative stress. PEITC and SFN have been shown to inhibit cancer growth and progression, while MIC also exhibit antitumor activity. Additionally, these compounds have neuroprotective effects, reducing oxidative stress and inflammation in the brain. The review highlights the potential of isothiocyanates as chemopreventive agents and their role in various health benefits.