Lack of food and depression

Patient: I ve been diagnosed with depression, my blood test show a low level of Lithium, after taking medication I think I have improved a lot, I resumed work and have an active social life, a true blessing, still I notice something: when I haven’t eaten for a while for example 2 or 3 hours after lunch time, I start having signs of depression I feel that everybody is antagonizing me and don’t feel generally well, so lack of food can cause psychic disorders???????????