Hi, Based from the information provided it seems that the crash diet which you opted for becoming thin is a primary cause for the loss of hair. Mostly the diet for getting thin consists a protein substitutes so that other body structures are not adversely affected. Now since you are a THALLASEMIA MAJOR PATIENT so you will have the iron over load in your body and the hair loss can be cause by iron over load. Here is the list of issues caused by iron over load 1) joint or stomach pain, 2) hair loss, a bronze, 3) gray or green skin color, 4) chronic fatigue, 5) depression and 6) infertility. As per my opinion your loss of hair is from IRON OVERLOAD and not from the crash diet. More over the minoxidil 5% normally increases the hair growth in 4 months if no improvement is found please discontinue the use of the drug as it can lead to various side effects. I still think it will not have much effect in your case, but you can give it a try, but in case of any serious side effects as listed below please consult doctor as soon as possible 1) dry cough, sharp or stabbing chest pain; 2) chest pain spreading to the arm or shoulder, nausea, sweating, general ill feeling; 3) trouble breathing (especially while lying down); 4) swelling in your legs, ankles, or feet; 5) rapid weight gain of 5 pounds or more; 6) fast or pounding heartbeats; 7) sudden numbness, weakness, headache, confusion, or problems with vision, speech, or balance; 8) fever, sore throat, and headache with a severe blistering, peeling, and red skin rash; 9) the first sign of any skin rash, no matter how mild. hope it helps. Dr. JAY PATEL