Well I noticed a big difference in how I felt when I took that 5 HTP yesterday. I have come to the conclusion that the amino acids I was taking was lowering my blood ratio of serotonin to overall large neural amino acids, thereby lowering my brain serotonin levels.
Serotonin does not cross the blood brain barrier as easily as many other large neural amino acids do. If the other amino acids are elevated then less serotonin can make it’s way to the brain.
When people eat they usually do not eat until they are full, but they usually eat until their mind tells them they are full. Our often rushed diets do not contain enough tryptophan (a precursor to serotonin) sometimes and thus the brain serotonin levels may be a slight bit low. Right before you eat (and once you begin to eat) your serotonin levels in your hypothalamus continue to rise until you are no longer hungry. Thus by increasing the steady state level of serotonin (assuming you have low serotonin levels) you find satiety much earlier in the eating cycle and eat less food.
Often times depression is caused by low serotonin levels and frequent overeating can be a suggestive symptom of depression.