This is a commonly asked question which depends on various factors. Protein is a macromolecule that is found in fish, meat, eggs, nuts, etc. Proteins have many important functions in the body, including supporting repair, growth, producing hormones and enzymes as well as making antibodies, balancing fluid levels and as an energy and potential carbohydrate source (Clark 2010).
The more exercise you perform, the more recommended protein is required. For moderately active people 0.8g per kg of body weight is recommended. Therefore a 60kg woman would need 75 grams of protein per day. With animal protein being about 22% per 100 grams of meat, a 100g steak would give you 22g towards your daily protein intake (Poliquin 2012).
For people who lift weights the recommendations are 1.7 – 2.0 grams of protein per kg of body weight every day, around 170 grams of protein for a 100kg man (Spruce 2004, Reimers 2008). For people who do more endurance work its 1.4 grams per kg (Spruce 2004).