Why shouldn't you copy someone else's meal plan?
In nutrition, generalizing is one of the most common mistakes among those who start this path to achieve their goals. Each person has their nutritional and caloric requirements depending on many factors, such as weight, sex, age and level of activity, physical, and that is why each person must follow a diet plan according to those needs.
If you want to lose weight or gain muscle mass, you will need a custom meal plan that really fits your nutritional needs, taking into account all the necessary factors.
A personalized diet is more than counting calories and dispensing with unhealthy foods, a diet plan means that you will provide your body with nutrients based on your goals. Plus, your diet MUST be something that you can actually STICK TO long-term, not just another fad diet that promises a fix by next week.
Don't copy someone else's diet, follow your own eating plan
Diet has a great impact on your life, from your appearance to how you feel, therefore, when it is inadequate, it affects your life on a small or large scale. Meal plans don't have to be complicated (although there are many fitness gurus pretending so).
Currently, on the Internet there are thousands of promising diet plans and diets, which can be useful to start, however, it is necessary to keep clear that they can work for some and not for others.
The body is dynamic and constantly changing, so the best decision is to opt for meal plans that consider your specific needs and goals. Diets require modifications during their development, these adjustments are specific to each individual, according to their response to new eating habits.
Each body has different characteristics that are important to keep in mind to establish what those nutritional requirements are. The main individual influencing factors are:
It is true that there are many reference tables regarding caloric needs in relation to the age and sex of each person, however, these are values that allow making plans based on approximations.
Metabolism works differently for each person, although some strategies are generally applied, adjustments should always be made with individual needs in mind.
A balanced diet requires an adequate distribution of macronutrients (carbohydrates, proteins, and fats) according to caloric and nutritional requirements. The distribution should be established individually for each person depending on the individual goals and factors.
The distribution of macro- and micronutrients together with the correct proportions of food is the key to success. 
Copying someone else's eating plan can not only lead to inadequate nutrition, but it can also affect you mentally because it can make you a victim of frustration.
Trying a diet that may have worked for a family member or friend can lead to frustration and decline. Generic or copied diets, in addition to not providing you with the nutrients your body strictly needs, can also increase your cortisol levels due to stress. Cortisol is a hormone released in stressful situations that can affect metabolism and muscle development.
A generic or copied eating plan from someone else can also jeopardize your health because improper eating can increase the risk of metabolic diseases.
Benefits of having your custom meal plan
How do you create a custom meal plan?
The goal of a personalized meal plan is to help you reach your goals while changing your eating habits in a healthy and safe way.
This is the initial step in designing a diet plan and consists of determining the weight and distribution of the percentage of body fat according to your sex and age to assess the performance of the metabolic rate, determine the body mass index and your caloric requirements. 
The objective of macronutrient distribution is to determine the proportions of carbohydrates, proteins, and fats that must be consumed daily.
The distribution of macronutrients is established based on your goals and these can be: weight loss, weight maintenance, or muscle mass gain. Food quality also plays an important factor in achieving goals.
Food-based on processed carbohydrates and refined sugars do not have the same influence on our body as a natural food-based on complex carbohydrates and rich in fiber.
Although caloric requirements play a fundamental role in body transformation, it is also important to take care of the quality of the food we eat. To eat healthily and achieve your goals, you must not only count calories, but you must also eat high-quality foods that really nourish your body. 
Establishing food portions is just as important as the type of food you eat because, even if they are healthy meals, inadequate portions can slow you down to achieve your goals.
Servings set the amount of each food to be consumed daily and are based on nutritional requirements. When establishing a meal plan, portions are established considering the calorie content of each food and its effect on the body.
Each food has a standardized serving, however, when it comes to a personalized nutritional plan, servings are calculated taking into account food selection and even timing of consumption. An important fact of managing the correct portions of food is that it guarantees an adequate supply of micronutrients and trace elements, key substances when establishing a healthy diet. 
Avoid premade diet plans and magic formulas. Everything happens through effort and change of habits!