Any eating plan that leaves entire food groups out is not a good one! Your body needs the nutrients in fruits, complex carbs, fats, and dairy. When I am cutting in I eat lesser amounts of carbs, fruits, and dairy, but I never cut them out completely.
What your friend is telling you WILL take weight off of you. It's by a method called Ketosis- It forces the liver to burn fat for fuel in the abscence of glycogen from carbs. However, this is extremely hard on the internal organs and can have a myriad of negative effects, from decreased vision in the immediate and short term to liver damage and kidney stones and other things in the long term. Additionally, as soon as you eat some carbs at the end, you will go right back to what you weighed before.
It's your body so it's your choice, but forwarned is forearmed.
| Body Fat %: 169.8