To design a diet plan that contains daily, weekly or monthy nutrition plan, divided and calculated per each meal, is not a simple job. Lot of factors needs to be considered in order to develop adequate diet plan. We need to consider sociological, psychological and culturological characteristics of the patient, also his habits that are not just related to food consumption, but habits in general. The patient`s environment has to be taken under consideration as well, occupation, working hours. If the patient, for instance, had a 12 hour shifts at work, with 1 hour break, he wouldn`t be able to follow diet plan that, perhaps, requires consumption of 5 meals per day in the strictly determined time frame per each meal. So there would be no point of prescribing such a plan if the patient couldn`t follow it. Diet plan has to be compatible with the working hours. Or, for instance, how diet plan that requires frequent consumption of potato would be well implemented if the patient didn`t like to eat potato. That diet surely wouldn’t work. Another example of ineffective diet would be a diet plan designed in a way that the first meal of the day is to be consumed at 7 am, and the patient doesn`t like to eat anything for the first 2 hours after waking up, and has a strong feeling of nausea in the early morning.

Apart of factors mentioned above, financial status f the patient has to be taken under consideration, because there is no point of prescribing a diet plan that is based on expensive ingredients, if the patient couldn`t afford it.

Diet has to be adapted according to the patient`s lifestyle conditions, and all the factors mentioned above need to be incorporated in it. Just in a very few cases, when we need to treat really serious illnesses, daily activities of the patient have to be organized according to the diet plan requirements, in order to prolong life spam, or improve quality of life.

It also needs to be understood that that every diet is unique, because every individual is unique. To men can have the same health problems, yet diet is not necessarily the same for them, because for one person certain type of food can be more appropriate than for the other. For example, two men have gastritis, one of them gets crumps, indigestion and bloating every time when eating bell pepper, and the other one has no problems whatsoever when eating peppers, perhaps even likes eating peppers. Patients also have different symptoms of the same disease, they have different clinical signs, different stages in illness progression, so different therapies accordingly. For instance, both patients could have gastritis, but at the first one fundus of the stomach is affected, and at the second one pylorus of the stomach is affected.

Diet plan for these two patients would be slightly different, accordingly.

The most important fact is that most of the people have many health issues, and with different combination of the illnesses. Diet is never designed just for one particular health problem, but it has to take under consideration the entire medical profile of the patient, and all pathologies.

To patients could have almost the same medical problems, five out of six, but the one that differs can completely change the diet plan. For example, patient with diabetes type II and obstipation could be prescribed medical nutrition therapy rich in spinach, and another patient with same issues, but also on anticoagulant medications, like warfarin, has to be really careful when consuming spinach, and diet plan for him needs to be designed according to the dosage of anticoagulants he is taking.

Another medical term that has lately aroused attention is microbiota of the gut.

Bacteria that are living in our gastrointestinal tract play a very important role in the process of digestion, absorption and excretion, and has been recently proven that they also have important role in our immunity, biotransformation of certain medications, chemical agents and substances associated to different pathologies of our body. Nevertheless, composition of the gut microbiota differs in each individual. Not only qualitatively, but differs quantitatively- percentage ratio between different species of the bacteria within one`s microbiome. Since they have a very important role in digestion process, macrobiotic bacteria should be also considered when designing the menu of one`s diet program. For example, it is very challenging to design a proper diet plan for the patient who has undergone the gut resection operation, when it`s necessary to restore the microbiota and increase the number of certain species, and at the same time not irritate mucosa of the gut with specific food.

Compatibility of different food should also be taken under consideration, because certain food is simply not good to be consumed at the same time with some other food, they might not get along in the same meal. Also, some food combinations are not recommended in certain illnesses, and on the other hand, same combination of food wouldn`t cause any problem for some other illness. Famous example would be widely spread anemia amongst the preschool and school children in Egypt during 60` and 70` of the last century, caused primarily due to lack of iron in blood. After many years of research, it was concluded that the main cause of this problem was not the lack of iron in common diet of the Egyptian children, but because of the excessive tea consumption among the children. Namely, it is the cultural thing that children in Egypt, since the early childhood, consume lot of tea. Those specific brands of tea they were drinking, contained high levels of tannins which bind iron and restrict it from being absorbed by enterocytes in our guts, but excreted as chelate through the feces. Solution was found by switching to different brand of tea that didn`t contain high levels on tannins.

Besides the proper food combination, it is crucial to pay attention to food and drug contraindications, because certain medications mustn`t be taken together with the certain food, and on the other hand, with some medications is even suggested to take bigger amount of certain food.

After all of these factors are considered in designing diet plan, it is also necessary to calculate recommended daily calorie intake, to calculate calorie distribution throughout the day, amount of calories in each meal, and to calculate the adequate ratio of macronutrients (carbohydrates, proteins and fat) for each meal. Because is it not the same ratio of proteins and fat, for instance, in breakfast, afternoon snack or dinner. And for the last, it is necessary to calculate caloric value of each single food in grams, which is to be consumed during g the day.

To design one diet plan is a very comprehensive and demanding job.