Improve Code To Output A Word With Most Frequent Letter?

The code is supposed to output a word from a sentence(from a sample file) with most frequently occurring letter in that word.

Example input: "Therefore, it is this word."

output: therefore

It currently uses 3 loops nested loops, is there a way to improve this?

public static String findWord(String file) throws IOException {
BufferedReader in = new BufferedReader(new FileReader(file));
String text, correctWord = null;
text = in.readLine();
StringTokenizer tokens = new StringTokenizer(text.toLowerCase(), " ,.?"); //split string into tokens of words only
int count = 0, numLetter = 0;

[code]....