The secret to good nutrition is very simple. Eat three balanced meals per day giving thanks for each one. The meals should contain the all the nutrients recommended by the nutritional researchers in the proportions and amounts they recommend. They only exception is during periods of illness when you should follow the recommendations of your doctor or specialist.
The biggest myth about food is that there is some scientific disagreement about what nutrients humans need. It is this myth that companies use to make huge profits selling cheap, junk food. Only a tiny fraction of the population gets enough of the vegetable protein, omega-3 fatty acids,nuts,fruits and vegetables that they need to remain healthy. People get hundreds of messages per day to eat junk food and unhealthy fad diets, but only one from their doctor to lay off the red meat and eat more fruits and vegetables. The fad diets all promote the myth that it is fattening to eat the fruits, vegetables, etc. needed in a healthy diet.
Food companies would have an advisory panel of nutritional researchers and a laboratory to analyze the food's chemical contents if they cared about the health of the consumer. Instead they spend the money on advertising to sell their defective products which contain who knows what.