Puberty is the period of physical and psychological transition from childhood to adolescence and sexual maturity, driven by rising sex hormones that activate the reproductive glands. Growth accelerates, body composition shifts, and secondary sexual characteristics develop over several years, with timing that varies widely between individuals. Nutritionally it is one of the most demanding phases of life: energy needs surge, and requirements for protein, calcium, iron, and zinc climb to support bone growth, expanding blood volume, and new tissue. Poor nutrition can delay puberty, while excess energy intake is linked to earlier onset. Eating disorders often emerge in these years, making puberty a critical window for nutrition education, adequate diet, and healthy attitudes to food and body image.