Mrs Brown thinks that fatness runs in families, and the GP explains that there is some truth in this. The narrator explains how bad feeding habits can start with the birth of a child, from putting sugar into milk to make it sweeter, to feeding children sweets and not letting them get enough exercise. The film then focuses on Valerie Smith, who comes from a broken home. She began eating chocolate to console herself after her father left, and the mother does not pay much attention to her. The GP explains that if Valerie receives no help, she will grow into a fat, breathless woman who must buy outsize dresses and sit by herself at dances as no one will want to dance with her. Then Jimmy Grant is seen. His mother is overweight but his father and brother are slim. Jimmy has been given a letter from school explaining that he is overweight and must see a doctor. He and his mother go to see the GP who has been narrating the film, and she weighs him and measures his body fat with callipers. The doctor explains that Jimmy must go on a diet, and although the mother initially wants a quick solution, agrees to help her son.