Whay is andrew so fat

His nutrition is most likely unhealthy and he doesn't work out enough

9 Most common causes of obesity

Physical inactivity.

Overeating.

Genetics.

A diet high in simple carbohydrates.

Frequency of eating.

Medications.

Psychological factors.

Diseases such as hypothyroidism, insulin resistance, polycystic ovary syndrome, and Cushing's syndrome are also contributors to obesity.