## Step 1: Define the symbolic representation of the variables
The variables are defined as follows: 
- $x_0$ represents 'milligrams of magnesium'
- $x_1$ represents 'milligrams of vitamin B9'
- $x_2$ represents 'milligrams of vitamin B12'
- $x_3$ represents 'milligrams of vitamin A'

## Step 2: Convert the objective function into a symbolic representation
The objective function to minimize is $1.53x_0 + 9.41x_1 + 1.22x_2 + 4.92x_3$.

## Step 3: List all constraints in symbolic notation
Constraints:
1. $17x_0 \leq 156$ and $x_0$ has a muscle growth index of 14, so $14x_0$ 
2. $21x_1$ 
3. $25x_1$ 
4. $16x_2$ 
5. $23x_2$ 
6. $17x_3$ 
7. $22x_3$ 
8. $21x_1 + 17x_3 \geq 21$
9. $17x_0 + 21x_1 \geq 16$
10. $21x_1 + 16x_2 \geq 37$
11. $17x_0 + 21x_1 + 16x_2 + 17x_3 \geq 37$
12. $23x_2 + 22x_3 \geq 40$
13. $14x_0 + 23x_2 \geq 43$
14. $25x_1 + 23x_2 + 22x_3 \geq 34$
15. $14x_0 + 25x_1 + 23x_2 + 22x_3 \geq 34$
16. $6x_1 - 10x_3 \geq 0$
17. $16x_2 + 17x_3 \leq 81$
18. $17x_0 + 16x_2 + 17x_3 \leq 138$
19. $17x_0 + 21x_1 + 17x_3 \leq 116$
20. $21x_1 + 16x_2 + 17x_3 \leq 47$
21. $17x_0 + 21x_1 + 16x_2 \leq 123$
22. $14x_0 + 25x_1 + 17x_3 \leq 163$
23. $14x_0 + 25x_1 + 23x_2 \leq 193$
24. $25x_1 + 23x_2 + 22x_3 \leq 177$

## 4: Define variable types
- $x_0$ is continuous
- $x_1$ is integer
- $x_2$ is integer
- $x_3$ is continuous

## 5: Write the Gurobi code
```python
import gurobi

def solve_optimization_problem():
    model = gurobi.Model()

    # Define variables
    x0 = model.addVar(lb=-gurobi.GRB.INFINITY, ub=gurobi.GRB.INFINITY, name="x0")  # milligrams of magnesium
    x1 = model.addVar(lb=-gurobi.GRB.INFINITY, ub=gurobi.GRB.INFINITY, vtype=gurobi.GRB.INTEGER, name="x1")  # milligrams of vitamin B9
    x2 = model.addVar(lb=-gurobi.GRB.INFINITY, ub=gurobi.GRB.INFINITY, vtype=gurobi.GRB.INTEGER, name="x2")  # milligrams of vitamin B12
    x3 = model.addVar(lb=-gurobi.GRB.INFINITY, ub=gurobi.GRB.INFINITY, name="x3")  # milligrams of vitamin A

    # Objective function
    model.setObjective(1.53*x0 + 9.41*x1 + 1.22*x2 + 4.92*x3, gurobi.GRB.MINIMIZE)

    # Constraints
    model.addConstr(17*x0 <= 156, name="cardiovascular_support_index_magnesium")
    model.addConstr(14*x0 <= 218, name="muscle_growth_index_magnesium")

    model.addConstr(21*x1 <= 156, name="cardiovascular_support_index_vitamin_B9")
    model.addConstr(25*x1 <= 218, name="muscle_growth_index_vitamin_B9")

    model.addConstr(16*x2 <= 156, name="cardiovascular_support_index_vitamin_B12")
    model.addConstr(23*x2 <= 218, name="muscle_growth_index_vitamin_B12")

    model.addConstr(17*x3 <= 156, name="cardiovascular_support_index_vitamin_A")
    model.addConstr(22*x3 <= 218, name="muscle_growth_index_vitamin_A")

    model.addConstr(21*x1 + 17*x3 >= 21, name="combined_cardiovascular_support_index_vitamin_B9_A")
    model.addConstr(17*x0 + 21*x1 >= 16, name="combined_cardiovascular_support_index_magnesium_vitamin_B9")
    model.addConstr(21*x1 + 16*x2 >= 37, name="combined_cardiovascular_support_index_vitamin_B9_B12")
    model.addConstr(17*x0 + 21*x1 + 16*x2 + 17*x3 >= 37, name="combined_cardiovascular_support_index_all")
    model.addConstr(23*x2 + 22*x3 >= 40, name="combined_muscle_growth_index_vitamin_B12_A")
    model.addConstr(14*x0 + 23*x2 >= 43, name="combined_muscle_growth_index_magnesium_B12")
    model.addConstr(25*x1 + 23*x2 + 22*x3 >= 34, name="combined_muscle_growth_index_vitamin_B9_B12_A")
    model.addConstr(14*x0 + 25*x1 + 23*x2 + 22*x3 >= 34, name="combined_muscle_growth_index_all")

    model.addConstr(6*x1 - 10*x3 >= 0, name="vitamin_B9_A_constraint")
    model.addConstr(16*x2 + 17*x3 <= 81, name="combined_cardiovascular_support_index_vitamin_B12_A_max")
    model.addConstr(17*x0 + 16*x2 + 17*x3 <= 138, name="combined_cardiovascular_support_index_magnesium_B12_A_max")
    model.addConstr(17*x0 + 21*x1 + 17*x3 <= 116, name="combined_cardiovascular_support_index_magnesium_B9_A_max")
    model.addConstr(21*x1 + 16*x2 + 17*x3 <= 47, name="combined_cardiovascular_support_index_vitamin_B9_B12_A_max")
    model.addConstr(17*x0 + 21*x1 + 16*x2 <= 123, name="combined_cardiovascular_support_index_magnesium_B9_B12_max")
    model.addConstr(14*x0 + 25*x1 + 17*x3 <= 163, name="combined_muscle_growth_index_magnesium_B9_A_max")
    model.addConstr(14*x0 + 25*x1 + 23*x2 <= 193, name="combined_muscle_growth_index_magnesium_B9_B12_max")
    model.addConstr(25*x1 + 23*x2 + 22*x3 <= 177, name="combined_muscle_growth_index_vitamin_B9_B12_A_max")

    # Solve the model
    model.optimize()

    # Print the solution
    if model.status == gurobi.GRB.OPTIMAL:
        print("Optimal solution found.")
        print("milligrams of magnesium:", x0.varValue)
        print("milligrams of vitamin B9:", x1.varValue)
        print("milligrams of vitamin B12:", x2.varValue)
        print("milligrams of vitamin A:", x3.varValue)
    else:
        print("No optimal solution found.")

solve_optimization_problem()
```

## 6: Symbolic representation
```json
{
    'sym_variables': [('x0', 'milligrams of magnesium'), ('x1', 'milligrams of vitamin B9'), ('x2', 'milligrams of vitamin B12'), ('x3', 'milligrams of vitamin A')],
    'objective_function': '1.53*x0 + 9.41*x1 + 1.22*x2 + 4.92*x3',
    'constraints': [
        '17*x0 <= 156',
        '14*x0 <= 218',
        '21*x1 <= 156',
        '25*x1 <= 218',
        '16*x2 <= 156',
        '23*x2 <= 218',
        '17*x3 <= 156',
        '22*x3 <= 218',
        '21*x1 + 17*x3 >= 21',
        '17*x0 + 21*x1 >= 16',
        '21*x1 + 16*x2 >= 37',
        '17*x0 + 21*x1 + 16*x2 + 17*x3 >= 37',
        '23*x2 + 22*x3 >= 40',
        '14*x0 + 23*x2 >= 43',
        '25*x1 + 23*x2 + 22*x3 >= 34',
        '14*x0 + 25*x1 + 23*x2 + 22*x3 >= 34',
        '6*x1 - 10*x3 >= 0',
        '16*x2 + 17*x3 <= 81',
        '17*x0 + 16*x2 + 17*x3 <= 138',
        '17*x0 + 21*x1 + 17*x3 <= 116',
        '21*x1 + 16*x2 + 17*x3 <= 47',
        '17*x0 + 21*x1 + 16*x2 <= 123',
        '14*x0 + 25*x1 + 17*x3 <= 163',
        '14*x0 + 25*x1 + 23*x2 <= 193',
        '25*x1 + 23*x2 + 22*x3 <= 177'
    ]
}
```