There is opinion regarding food so everyone eats it. In case health is the main aim, then opinion does not matter.
According to the belief of many people average cooked diet based on official food pyramids is fine. Some eat fast food while others have faith on eating plant foods onlyEveryone can make arguments on what they believe. They can give instances of people who have lived long. Some believe that animal life should not be sacrificed for food. Eating belief seem to taken on the religious character. People feel zealous regarding food and do not like others to interfere in their affairs.
Health is associated with what we insert into our mouth. It is quite easy to be fooled because wrong food choices may not have their full influence late in life. Nutrition can pass through to affect generations.
Food ideas are like religion and many different sects can claim to have the truth. The body is adaptable and will make attempt to survive. If food is not right there is no danger. The body will be stressed beyond its ability to adapt. 
Foods that have vitality
This can result in disease and loss of vitality. You need to be careful prior to subscribing to claims regarding what is good or what is not good to eat. The test of the health idea is far into the future. Human beings are adapted to specific types of food.
The most of the foods we eat are a product of agricultural revolution and have a small part of the history of humans. The natural adapted to food for human can predate them. We are full developed biologically before agriculture and any other way of food processing.
This means that whatever diet humans eat is the perfect diet because that diet is responsible for the development of the human organism.
In case we do not eat according to this principle, our bodies are in deficiency and toxin exposure. The result of the generations that ignore this principle is exhaustion of our digestive processes.
Natural foods that we consume
If the natural food is raw you will live. This is fully known by the law of Biogenesis. Life comes from pre-existing life. We have never seen life springing from non-life. In case we eat living foods, we increase our own life.
In case we eat foods that are dead and lacking in nutrients we can become dead. This aspect will not happen fast but the adaptive reserves are fatigued and we become like dead food we eat. A basic feature of our natural diet is that it is raw.
Studies in the past have revealed that they ate as their genes and as the environment told them to do. We had our natural bodies like every other creature. Every organism eats raw food that are found in nature.
The question arises that would oatmeal porridge qualify. The answer is that oatmeal porridge is not found in nature. Another question is that would hamburgers, French fries, cereals, quality? The answer is a simply no because none of these foods can be found in nature. 
Those of you who are in a panic of the thought of eating raw foods are right because in them there is an element of food borne pathogens. The danger is far less than the danger of lifetime eating processed foods. Raw natural foods are safe or else our ancestors may not have survived.
You need to imagine yourself in nature in absence of modern technology. You have to then ask yourself the question about what would you eat? You can eat fruits, nuts, insects, plants, honey, worms, eggs, milk and animal flesh.
These are the only food items found in nature that are found to be digested without the need of any technology. These foods are the foods of nomadic societies. You need to imagine yourself placed back in time that you have a family to feed.
Conclusion
You would be looking for the calorie and nutrient foods that you can find. You can let the herbivorous do the grazing and digestion with their stomachs that can convert plant material into edible protein and fat.
We need to eat that product that nature gives to us and that we can digest. It suits our natural bodies with natural food. Foods like tofu, lettuce, et are marketed as great health foods. They are not natural human foods. They in the raw precooked form are toxic.
Raw soyabean consists of a great deal of chemicals that can inhibit growth and can cause excessive harm to the enzymes in the body. If you have more of them you can possibly die. Modern grain products are outcome of agriculture and their raw form are toxic and not digestible.
In the nature one can never find kernels of rice, wheat or barley if they are eatable in their raw form.