There are actually physical reasons why people do not eat. Some may say it's a control issue, but I have seen infants and very young children with this problem! So that proves that it is, at least in some individuals- a physiological issue. Prescription or street drugs can cause it, and many times it is caused by a nutritional deficiency. Toxins can cause it as well.
I have been studying nutrition and the effects of malnutrition on the body for 10 years. These more common deficiencies come to mind:
Vit A: Low vitamin A will cause a lack of appetite. Children NEED to eat animal fat to get their A because they cannot make the conversion from beta carotene. So children with an aversion to animal protiens could have a vitamin A deficiency. Protien, fat, and zinc are required for vitamin A binding...again protien is an important key. I see children who have very high grain diets tend to have aversions to protiens, and aversion to eating in general. So a key for these children is to try to cut down all those grains.
Protien deficiency leads to vit a deficiency/anorexia.
Chronic fatigue can be a symptom of thyroid malfunction, and the thyroid requires more vit A than any other organ.
B vitamin (Thiamine, B9, B1(benfotiamine) ,b12) deficiency causes anorexia, and fatigue. B vit deficiency is VERY common. Liquid b complex drops under the tounge (to help with absorption) daily will help. Vit E is needed to convert b12 to it's active form. So eat someting high in vit E (raw red palm oil is very high) or take some E with it .
Iron deficiency can cause anemia, which will cause chronic fatigue, and it will also causes anorexia/ loss of appetite. Iron is a heavy metal which does not leave tissue easily, therefore overdose/iron poisoning can easily occur in those taking supplements. People should not take Iron without a doctor doing a blood test and showing a clear deficiency.
Magnesium deficiency is a leading factor in depression. Anorexics can have very very low magnesium, and magnesium is needed for heart function. When magnesium is low, it means that blood calcium is high, and that causes low appetite. Magnesium is also crucial for metal detox. Magnesium is one of those minerals that probably MOST people are very deficient in.
Hypervitaminosis D (overdose of vit D from supplements) causes anorexia.
Zinc deficicency can cause loss of taste,smell and appetite and can help anorexia. Zinc is needed for Vit A uptake.
Heavy metal poisoning can cause anorexia and depression. Aluminum is one that I remember. NCD zeolite is a chelator of metals.
Strep bacterial overgrowth can cause anorexia.
http://www.vaccinetruth.org/virus_and_mental_illness.htm
I would , no matter what, start giving her fulvic acid. She is likely to have several trace mineral deficiencies at once. Fulvics typically has 60+ trace minerals . It is a quick drink of a rather tasteless liquid but it feeds down to
the cellular level. Giving at the same time as other vitamins will help them get absorbed. I would avoid muti vitamins because some of the ingredients can cause further defciencies. Vit B, and magnesium are very
safe and are basics.