Find the biggest age

JavaScript

//Data
data = {"people": 
 [{"male": [
   {"name": "Bob" ,"age": "32"}, 
   {"name":"Mike", "age":"31"}
  ]}, 
 {"female": [
   {"name":"Jessica", "age": "24"}, 
   {"name":"Ann", "age": "23"}
 ]}]}

//Function
var age = 0;

data["people"].forEach(function(item) { 
    for (var key in item) {
        if (item.hasOwnProperty(key)) {
            item[key].forEach(function(person) {
                if (person.age > age) {
                    age = person.age;

                }

            });
        }
    }
});
console.log(age);