In an endothermic reaction, energy is

Endothermic reactions are reactions that require external energy, usually in the form of heat, for the reaction to proceed. ... Therefore, the change in enthalpy is positive, and heat is absorbed from the surroundings by the reaction.

Explanation:

protein makes up the building blocks of organs, muscles, skin, hormones and pretty much everything that matters in your body.

some choices are:

peanut butter

seeds

eggs

yogurt

meats

fish

so pretty much meat, dairy, nuts, and grains.