Our body is the only source to do all the works of our life. We need body to do religious, economical, social, moral and spiritual works. Therefore, we need to remain healthy. It has been said that- 
‘Shariramadyamkhalu dharma sadhanam I’
Physical health means not only healthy body but healthy entire personality also. There are four ingredients of it-
1)    Physical
2)    Mental
3)    Economical
4)    Spiritual

Physical health

As its name, body needs to be healthy first. Because no work is possible without healthy body whether it is enjoying worldly prosperity or attaining spiritual bliss. Two things are important for keeping body healthy-
1)    Diets contribute around 70 percent in keeping body healthy. 
2)    Daily exercise contributes around 30 percent in keeping body healthy. 
Therefore, we need to control on our diets and avoid fried and packaged food items, maida, etc. Always keep in mind to consume light diet. Chew the food. The brain gets its message after 20 minutes.  
Do exercise daily and regularly. Try to do exercise of all the body organs. Try to do exercise in various postures so that body can function properly. 
However, it would be justifiable that we do exercise and consume diets under guidance of any expert. Otherwise, many a times, it makes adverse effect on our body. Yogic postures are highly useful for exercise. But as we know that postures give no desired benefit without abiding by yam and niyam. Therefore, yog is not an exercise but a mean of leading a healthy life. 

Mental health

Few years ago, people used to give no proper attention on the mental health. Even today in the rural areas, people prefer not to talk on mental health. In the urban areas too, people conceal it to avoid getting treated themselves as insane. It needs to be understood that as mind also falls prey to diseases in line with body. Therefore, we also need to keep mind healthy. Mind plays an important role in doing any work. It has been said-
‘If mind wins, we win battle, if mind loses, we lose battle’
We need to keep two things in mind to keep our mind healthy-
1)    Pranayam
2)    Reading knowledgeable books
We need to read good books. It has been said that books are the best friends of the human beings.
Mental health includes emotional health which comprises information regarding yourself, awareness, social awareness and building relationship, etc. Emotional intellect means helping others, listening them patiently, encouraging yourself continuously, controlling your emotions, etc. It’s possible only through pranayam and exercise.

Economical health

We need to be financially empowered to leading a healthy life. It’s possible only through hard labour. Without economically self-reliant, other activities of life get derailed. Therefore, the scholars treat homely life as the best way. It’s the best ashram of all. Therefore, we need to acquire knowledge properly in the celibacy ashram so that we need to earn money as per the religion in future. It has been said-

‘Arthagamonityamarogita cha, priya cha bharyapriyavadini cha,
Vashyashchaputraarthakari cha vidya, shad jivalokasyasukhanirajan I’

It means that those people who have enough money, healthy body, loving brothers, obedient sons and daughters and knowledge are prosperous in the world. 
Economic freedom in the celibacy ashram means acquiring more knowledge in the limited resources. Those students who visit to foreign universities to study are allowed to do few hours of work for earning money so that they can know importance of money in their life. 

Spiritual health

Spiritual health doesn’t mean that you remain offering prayer to the god. It means that you must know aims and objectives of life. You must participate in good thoughts of the society. You must contribute in social welfare. Your life should be based on values. 

Truth, non-violence, asteya, aprigrah, celibacy, tap, satisfaction, self-study, remembrance of the god, kindness, forgiveness, donation, duty, etc are some of the good merits which need to be assimilated in our life. These are highly important for overall development of our life. Proper path is essential for getting success in life. Otherwise, we will get derailed.
Coordination of all the four areas is essential for health. Generally, people consider that earning money, conservation of divine or moral values and study should be in homely asram, sanyas and celibacy respectively. it has been said that-

Prathamenarjita vidya, dvitiyenarjitamdhanam,
Tritiyenarjitampunyam, chartuthekimkarishyati I

It means that those people who didn’t acquire knowledge, money and divinity in celibacy, homely ashram and sanyas respectively can do nothing in vanprashtha. But it’s not proper in the practical. We need to keep coordination of all the four stages for overall development. 
Therefore, overall development is the need of the hour for keeping physical, mental, economic and spiritual health. They are the factors of happiness. The scientists have arrived at conclusion that the following hormones in the body keep us happy-

1)   Dopamine- Secretion of this hormone takes place when we consume tasty food items and do favorable works. 
2)   Serotonin- It makes an impact on the capacity of sleep, hunger, memory, learning, etc. Its secretion takes place during running, meditating, walking, swimming, cycling, etc. 
3)   Oxytocin- It’s also known as love hormone. Its secretion takes place during hugging, praising, playing with children and helping someone with no self-interest. Mother feeds her child due to his hormone. 
4)   Endorphins- It’s painkiller of the body. Its secretion takes place during laughing, exercising, etc.

Clearly, all the four hormones are the sources of happiness. They are associated with our health. Then question arises that what should we do to keep us healthy and happy?

We can remain happy and healthy by doing following works-
•    Walking
•    Exercising
•    Laughing
•    Consuming balanced diet
•    Meditating
•    Helping others
•    Sleeping properly
•    Increasing social network
•    Controlling stress
•    Believing in the ultimate power

If we do all the aforesaid activities in our life, we will remain happy and healthy. There are two obstacles in its path-

•    Laziness
•    Habit

We can get rid of these obstacles by keeping our goal in mind and trying to do it. Don’t do haste in this work and get discouraged.
Now question arises that what’s the bliss? This bliss is beyond health and happiness. Aanandmayakosh comes after annamaya, manomaya, pranamaya, vigyanmayakosh. We can find this aanandmayakosh on the path of the best. Those people who love can get temporal happiness. They fail to get bliss. Living in coordination is essential for getting bliss. The Ishavasyopnishad says that-

Ishavasyamidamsarvamyatkinchitjagatyamjagat I
Tena tyaktenabhunjitha ma gridhahkasyasviddhanam I

It means that the people should enjoy the worldly items with a sense of sacrifice. Self-realization is called bliss which is simplicity and awareness. The Mundak Upnishad writes that the weaker people (physical-mental-intellectual-soul) fail to get soul. Neither insane nor aimless people get this. Those who keep coordination among religion, science, sanyas and yog can get this bliss. 
Purification of body and mind and agility are the first and last criteria of being happy, healthy and blissful.  

Coming towards deformity from the nature is in fact disease while returning from deformity to the nature is Wellness and good health. 

What is Wellness 

Being healthy from physical , mental , social and spiritual point of view is in fact the state of good health. 

Parameters of physical Wellness 

•     Thereere should be no disease
•     There should be no pain 
•     There should be a sound sleep ( 5 to 8 hours a day)   
•     Feeling good hunger or appetite 
•     Clearing stomach on time and in sufficient quantity 
•     Feeling light as if there is no burden  of body 
•     Body mass index must be maintained. 

Mental health 

There should be a positive thinking and there must be a practice to be in present and one should not be deeply concerned about past and future. 

Social Health 

Family, society, Nation and the World must be seen with the idea of positivity and Vasudhaiva Kutumbakam has to be adopted as a motto of life which means the whole world is a family.

Spiritual health

Situated in the shelf which means the feeling of soul consciousness must exist. 

What is the disease

Disease = Dis + Ease imbalance in body functions and its constituents which means imbalance is main cause for diseases and the cause of of diseases is going from nature to deformity. 10 body and the universe are made of panchmahabhoot which includes Aakash the sky ,Vayu- wind , Agni -fire , water - Jal, and Prithvi -the earth. When all these elements are in balance there has to be Wellness when they are in imbalance there will be birth of diseases. The more we are getting away from the nature we are getting the more deformed. 

There is a great scarcity of the element of sky and we have filled our houses with sofa sets almirahs and deserts but condition of air pollution is not allowing the people of the cities like Delhi to breathe freely.
The main source of the fire element is the sun and today it is Ironic that India is a country where the sunlight is in abundance even then majority of Indians are deprived of vitamin D because we fear of getting dark skin and dislike to go in the sun and stay in the multi storey buildings and in such buildings sunlight hardly enters therefore people are deprived of Sunlight more over pollution is also preventing sunlight to come to us. 
This is a well known fact that water is life but today's people prefer to drink cold drinks tea in place of water which is leading to to serious health complications and the water that we are drinking has also become contaminated due to Excess use of chemical based fertilizers and pesticides.
Power connect with earth has also Bheem destroyed and it is also well-known fact that our body is made of soil and one day it will get destroyed in the soil but in our lifetime we are getting more and more away from the soil. Just see our own life and we will know that in 24 hours time how long do we stay in contact with mother earth because when we are outside we hardly take away our feet from our shoes and even on the floor of our houses we have covered with mattresses and sufficient synthetic methods.
Our children naturally like to play in the soil but we force them to keep away from so I'll fearing that they could be caught by infections at the same time it is also a fact that soil can clean our face much more than what chemical based cleanser do even then we use chemical based soaps and keep away from soil.
Nature has given us Amrit that is nectar in the form of natural food like fruits vegetables whole grain but by using chemical pesticides chemical fertilizers flavour and preservatives we have made our food poisonous. 
Nature has given us night to allow us to have rest but we have developed habits of keeping awake like animals who wander in the night and it is also fact that physical hard work is must for good health but due to Excess use of machines we use our body least and nature has provided us so many Herbs to fight diseases but instead we are using chemical based medicines with women's side effects. 
This way the deformity is that we are witnessing around us is the main cause of birth of serious diseases in our lives and for good health we will have no option but to return to the nature. 
For this the first change that we will have to incorporate in our lives is of ideas and in the race of modern way of lifestyle we have forgotten the value of life and we are destroying nature for our greed which is leading to deformity is therefore we will have to focus on the need for returning to the nature because nature can fulfill all our needs but not Desire. 
Then the first biggest change will have to be to establish the view of of being grateful to the nature rather than putting forward our demands to the nature and the elements like anger, fear , stress , becoming upset, depression and ill will are deformities on the other had love, sacredness , strength, Wellness, happiness, are natural thoughts. Ill will affect every cell of our body and make us unwell on the other hand positive thinking make us healthy.
Another change will have to be incorporated at the level of food because contaminated food is giving birth to so many diseases and the medicines which we have been taking for the treatment of these diseases have also become a part of our food habit because many people take 8-9 tablets every day. Now it is high time to make our food as a medicine. 
Our food contents almost all medicines are needed for healthy body and by using them properly we can become free from all types of diseases because the way nature has provided us natural food to us we should take them exactly the way they are and we should not allow any deformity in our food. Which means should eat natural food in the natural form like fresh fruits raw vegetables sprouts are considered to be the best vegetables and if one cannot eat them directly then we can boil it a little bit and we should also maintain an optimum level of natural fibre in our food grains and natural ingredients of milk God and he must be maintained and keep away from bad food like tea coffee cold drinks fried food spicy food abundance of chilli in food sugar find flower preservatives besides packaged food fast food artificial flavour and colorants. 
The thought change which is most required is to Resort to physical exercise and work out because using artificial means of life like television laptop mobile phones vehicles automobiles and Home appliances like mixer grinder washing machines etc are keeping away from physical workout.
Latest return to the nature again and walk in the open air air and walk on the soil barefoot and practice yoga everyday and the work that we can do by using our hands should not be replaced by machines and cleaning of the floor of our home grinding spices and food grains by using our hands which means grinding them physically is the most advisable thing.
This way proper thinking proper food and proper physical workout will help us to return to the nature and get complete Wellness.