In addition to the usual problems of anticipating problems with the safety of laboratory experiments of classroom demonstrations, it is common for students to ask advice from biochemistry teachers about diets. Many students are interested in fad diets (e.g. high protein/low carbohydrate) to cause weight loss. Students frequently ask about mechanisms of manipulating their metabolism (e.g. ingesting vinegar or hydrogen peroxide to stimulate metabolic rate). Other students are curious about supplements (e.g. creatine) that will give them increased athletic performance or help them sculpt their bodies.
Unless you are a physician, it is recommended that you be very careful about endorsing or recommending anything except a combination of a healthy diet and sensible exercise.
