The same thing is true for nutrition as it is for exercising. People tend to be aware of the physical implications of eating good and bad food, but not of the mental ones.
A growing field of research called nutritional neuroscience is assisting in our knowledge of the connections between diet and behavior, cognition, and emotions.
The nutritional deficiencies, including zinc, vitamin D, omega-3 fats, iodine, and magnesium, and consuming a lot of sugar and unhealthy fats, all add up to the deterioration of mental health.
Processed foods are highly correlated with the increased risk of chronic stress, depression, anxiety, and ADHD.
Try to find healthy substitution food options for the stuff you frequently eat. For example, you can drink a chocolate protein shake when craving sugar.