The aid lifeline for Umm Muhammad and hundreds of thousands of other Palestinians is now under existential threat as Israel lays siege to Gaza once again.

Israel’s cutoff of food, fuel, medicine and other supplies to Gaza’s 2 million people has sent prices soaring and humanitarian groups into overdrive trying to distribute dwindling stocks to the most vulnerable.

The food aid is what’s keeping us alive,” one Gaza resident says. As Israel halts aid going into the enclave, CNN’s Jeremy Diamond explores the impact on people who rely on this lifeline for survival.