Raw foods are more nutritious

It depends on the food. Many foods such as fruit and vegetables, and to a lesser extent meat and fish, are traditionally eaten raw. Generally, cooking results in the loss of some nutrients (see also THE WAY VEGETABLES ARE COOKED AFFECTS THEIR NUTRIENT CONTENT and FROZEN VEGETABLES ARE LESS NUTRITIOUS THAN FRESH VEGETABLES). On the other hand, cooking can make some foods more palatable, safe to eat and reduce the level of some types of pesticide. Raw meat and fish can easily be contaminated by bacteria which are usually destroyed during cooking. The risk of food poisoning from eating raw meat and fish needs to be carefully weighed against any perceived benefit. It would be prudent to only eat raw meat and fish that has been obtained from a reputable source or prepared in a dependable restaurant.
Nutritionally, there is unlikely to be any significant benefit in consuming raw meat or fish. Individuals with cancer, liver disease, diabetes, chronic gastrointestinal disease or conditions causing impaired immunity should not risk eating raw meat and fish, which could be contaminated.