There’s no one-size-fits-all diet. For example, some people in a 2015 study of 800 Israeli volunteers got their biggest blood sugar spike from bananas or bread, others from a sugary cookie. Now, the U.S. National Institutes of Health (NIH) is making a major push to understand these individual differences. Last week, the agency announced what it calls the largest study yet to probe “precision nutrition.” The $156 million, 5-year effort will examine how 10,000 Americans process foods by collecting data ranging from continuous blood glucose levels to microbes in a person’s gut. Ultimately, it might enable nutritionists to tailor diets for individuals. The study is part of a broader push at NIH to boost nutrition science.