Definition by WHO:

Mental health is a state of mental well-being that enables people to cope with the stresses of life, realize their abilities, learn well and work well, and contribute to their community. 

OR

Simply, mental health refers to how we think, feel and behave.

There are various types of mental health problems, certainly have no boundaries of age and sex. Among them we basically focused on the prevention of common mental health problems.
 Depression:  Depression causes feelings of sadness, hopelessness, and reduced energy.
 Anxiety: Anxiety creates feelings of nervousness, hopelessness and fearful.
 Stress/ Tension: a state of worry or mental tension caused by a difficult situation. It could be a normal state of mind however if it goes for a long time might turned into mental health problem.
 Anger: Anger can be a symptom of both anxiety and depression, as well as other mental health conditions.

Causes

There is no any exact or specific causes of mental health problems. Mental health can have a wide range of causes. The following factors could potentially result in a period of poor mental health:
 Physical: Childhood abuse, trauma,
 Stressful life situations: such as financial problems, tragedy, a loved one's death or a divorce
 Environmental: Social isolation, discrimination and stigma including racism, caste system in some countries, domestic violence, poverty, social disadvantage, homeless
 Substance abuse and alcohol problems.

Basic warning signs of Mental Health Problems (MHPs).

 Thinking problems: Confused, Compulsive, Negative, Suicidal thoughts
 Emotions Problems: Feelings of extreme highs and lows, Low self-esteem, excessive fears, sad and worries
 Ignorance: Avoiding social, family, personal (Job/school/ college) responsibilities and Inability to cope with the problems and daily activities.
 Changes in sleeping and eating habits, Laziness.

Simple guidelines to resolve Mental Health Problem (MHPs)

 Take care of your physical, emotional, mental and spiritual states. (Yoga, exercise, meditation)
 Share your feelings with the closer one
 Look for counselling with the appropriate personal/ counselor.
 Work at least 4-5 hours a day.
 Apply discipline in life.
Mental health conditions, such as depression or anxiety are real, common and treatable. Recovery is possible.