I had a doctors appointment today and he said that I lost 3 kilos since my last visit and he sent me to get my blood taken to check my thyroid and iron levels and more. They took 4 viles of blood and I get the results tomorrow. He also told me to eat lots of fruits and to drink Boost or Ensure because since I'm not eating much I need my vitamins and I need to gain weight. I was reading up on it and a lot of people were saying that its more of a multivitamin drink than a weight gainer drink but some people were saying that it helps to gain weight? I'm not sure. Will it help me gain weight or only provide me with the vitamins. I'm 18, 5'6" and weigh 106 pounds.