Because he is now better-informed, jack wants to cook healthier meals. which recommendation should he avoid?

There is so misinformation about staying away from carbohydrates. What Jack should realize is that everyone needs a balance of fats, about 20% of your calories, proteins, about 0.5 to 1.0 gram per body weight, then using a total calorie estimation, figure how many calories should come from carbohydrates. They really are important for energy.