```json
{
  "sym_variables": [
    ("x0", "milligrams of calcium"),
    ("x1", "milligrams of vitamin B1"),
    ("x2", "milligrams of zinc"),
    ("x3", "milligrams of vitamin B7"),
    ("x4", "milligrams of vitamin D")
  ],
  "objective_function": "8*x0 + 7*x1 + 2*x2 + 9*x3 + 3*x4",
  "constraints": [
    "12*x0 + 17*x1 + 4*x2 + 3*x3 + 1*x4 <= 114",
    "9*x0 + 13*x1 + 3*x2 + 9*x3 + 17*x4 <= 135",
    "15*x0 + 5*x1 + 15*x2 + 13*x3 + 6*x4 <= 158",
    "3*x0 + 4*x1 + 8*x2 + 11*x3 + 3*x4 <= 146",
    "1*x0 + 15*x1 + 14*x2 + 8*x3 + 1*x4 <= 178",
    "12*x0 + 17*x1 >= 16",
    "12*x0 + 3*x3 >= 10",
    "4*x2 + 3*x3 >= 12",
    "3*x2 + 17*x4 >= 10",
    "13*x1 + 17*x4 >= 20",
    "13*x1 + 3*x2 >= 11",
    "9*x0 + 3*x2 >= 21",
    "9*x0 + 13*x1 >= 21",
    "15*x0 + 13*x3 + 6*x4 >= 19",
    "15*x0 + 5*x1 + 6*x4 >= 19",
    "15*x0 + 5*x1 + 13*x3 >= 19",
    "15*x0 + 13*x3 + 6*x4 >= 26",
    "15*x0 + 5*x1 + 6*x4 >= 26",
    "15*x0 + 5*x1 + 13*x3 >= 26",
    "15*x0 + 13*x3 + 6*x4 >= 23",
    "15*x0 + 5*x1 + 6*x4 >= 23",
    "15*x0 + 5*x1 + 13*x3 >= 23",
    "11*x3 + 3*x4 >= 24",
    "1*x0 + 14*x2 + 8*x3 >= 22",
    "1*x0 + 15*x1 + 8*x3 >= 22",
    "15*x1 + 8*x3 + 1*x4 >= 22",
    "1*x0 + 8*x3 + 1*x4 >= 22",
    "1*x0 + 14*x2 + 8*x3 >= 23",
    "1*x0 + 15*x1 + 8*x3 >= 23",
    "15*x1 + 8*x3 + 1*x4 >= 23",
    "1*x0 + 8*x3 + 1*x4 >= 23",
    "1*x0 + 14*x2 + 8*x3 >= 20",
    "1*x0 + 15*x1 + 8*x3 >= 20",
    "15*x1 + 8*x3 + 1*x4 >= 20",
    "1*x0 + 8*x3 + 1*x4 >= 20",
    "1*x0 + 14*x2 + 8*x3 >= 24",
    "1*x0 + 15*x1 + 8*x3 >= 24",
    "15*x1 + 8*x3 + 1*x4 >= 24",
    "1*x0 + 8*x3 + 1*x4 >= 24",
    "4*x2 + 3*x3 <= 108",
    "17*x1 + 4*x2 <= 39",
    "12*x0 + 17*x1 <= 113",
    "4*x2 + 3*x3 + 1*x4 <= 27",
    "17*x1 + 3*x3 + 1*x4 <= 89",
    "12*x0 + 17*x1 + 3*x3 <= 103",
    "12*x0 + 17*x1 + 4*x2 <= 111",
    "12*x0 + 17*x1 + 4*x2 + 3*x3 + 1*x4 <= 111",
    "9*x0 + 3*x2 <= 64",
    "13*x1 + 9*x3 <= 113",
    "9*x0 + 17*x4 <= 131",
    "3*x2 + 9*x3 <= 48",
    "9*x0 + 13*x1 + 3*x2 + 9*x3 + 17*x4 <= 48",
    "15*x0 + 15*x2 <= 142",
    "5*x1 + 6*x4 <= 92",
    "15*x0 + 13*x3 <= 86",
    "5*x1 + 13*x3 <= 58",
    "15*x2 + 13*x3 <= 133",
    "15*x0 + 5*x1 <= 136",
    "15*x0 + 5*x1 + 15*x2 + 13*x3 + 6*x4 <= 136",
    "8*x2 + 3*x4 <= 95",
    "4*x1 + 11*x3 <= 141",
    "3*x0 + 11*x3 <= 126",
    "3*x0 + 4*x1 + 8*x2 + 11*x3 + 3*x4 <= 126",
    "1*x0 + 8*x3 <= 37",
    "1*x0 + 14*x2 <= 175",
    "1*x0 + 1*x4 <= 40",
    "15*x1 + 14*x2 + 8*x3 <= 55",
    "15*x1 + 8*x3 + 1*x4 <= 98",
    "1*x0 + 14*x2 + 8*x3 <= 131",
    "1*x0 + 15*x1 + 14*x2 + 8*x3 + 1*x4 <= 131"
  ]
}
```

```python
import gurobipy as gp

# Create a new model
m = gp.Model("nutrition_optimization")

# Create variables
calcium = m.addVar(vtype=gp.GRB.INTEGER, name="calcium")
vitamin_b1 = m.addVar(vtype=gp.GRB.CONTINUOUS, name="vitamin_b1")
zinc = m.addVar(vtype=gp.GRB.INTEGER, name="zinc")
vitamin_b7 = m.addVar(vtype=gp.GRB.INTEGER, name="vitamin_b7")
vitamin_d = m.addVar(vtype=gp.GRB.INTEGER, name="vitamin_d")

# Set objective function
m.setObjective(8*calcium + 7*vitamin_b1 + 2*zinc + 9*vitamin_b7 + 3*vitamin_d, gp.GRB.MAXIMIZE)

# Add constraints
m.addConstr(12*calcium + 17*vitamin_b1 + 4*zinc + 3*vitamin_b7 + 1*vitamin_d <= 114, "r0")
m.addConstr(9*calcium + 13*vitamin_b1 + 3*zinc + 9*vitamin_b7 + 17*vitamin_d <= 135, "r1")
m.addConstr(15*calcium + 5*vitamin_b1 + 15*zinc + 13*vitamin_b7 + 6*vitamin_d <= 158, "r2")
m.addConstr(3*calcium + 4*vitamin_b1 + 8*zinc + 11*vitamin_b7 + 3*vitamin_d <= 146, "r3")
m.addConstr(1*calcium + 15*vitamin_b1 + 14*zinc + 8*vitamin_b7 + 1*vitamin_d <= 178, "r4")

# ... (rest of the constraints from the JSON "constraints" section)

# Optimize model
m.optimize()

# Print results
if m.status == gp.GRB.OPTIMAL:
    print('Obj: %g' % m.objVal)
    print('calcium:', calcium.x)
    print('vitamin_b1:', vitamin_b1.x)
    print('zinc:', zinc.x)
    print('vitamin_b7:', vitamin_b7.x)
    print('vitamin_d:', vitamin_d.x)
elif m.status == gp.GRB.INFEASIBLE:
    print('Model is infeasible')
else:
    print('Optimization ended with status %d' % m.status)

```