Does bad nutrition correlate with other disorders?

Yes.

Every digestive problem can be traced back to the quality of nutrition; tooth decay, lack of taste, excess gastric acid, painful bowel problems, and frequent constipation leading to haemorrhoids and weakened kidneys. Insufficient nutrition even has negative effects on vision. Furthermore, the lack of adequate nutrition causes degeneration of the bones, loss of muscle mass and cardiovascular problems. These are caused by the same reason that causes the occurrence of aesthetic problems as well, such as blemished skin and eczema. Even food allergies can develop with symptoms of itching and rash. 

In addition, we have psychological disturbances like a distorted body image that often causes low self-esteem in many children.

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