I think this is an opinion-based question. Most Hindu families living in urban areas these days have lost track of their roots and tradition on how to celebrate birthdays. They now simply resort to imitating the West by lighting candles on a birthday cake and blowing out candles.
The more pertinent question is:
How should a Hindu celebrate the birthday?
First off, it is very important to celebrate ones birthday - should not neglect it. One should celebrate the birthday on the tithi they were born rather than a specific date from the English calendar. (You can calculate your Janmatithi from here).
Wake up very early in the morning and start your day with abhyanga-snana i.e. take bath after applying oil, head to toe.
Before you take the bath, have your parents and elders also apply some oil to your head and back (spine). Take their blessings. It's most important to take blessings of your parents and guru on your birthday. The elders in return usually bless by uttering:
After taking bath, pray to your kula-devata or ishta-devata.
Then take a concoction of cow milk, jaggery and black sesame seeds. Turn to east and swallow the mixture 3 times (achamanam). This should prevent any obstacles you might face now until your next birthday.
Next, remember the names of the 7 chiranjivi's (by birth):
Ashwathama, Mahabali, Vyasa, Hanuman, Vibhishana, Kripacharya and Parashurama. Or simply say out loud:
Ayushya Suktam from the Yajur Veda can be recited for a long and healthy life. Optionally, Ayushya Homam may also be performed.
Visit the nearest temple
One can eat the most delicious food they like but should maintain brahmacharya the entire day.
If you can afford, donate food and clothes to the needy. If you cannot, feed green grass to a cow and circumambulate (pradakshina) the cow 3 times.
Even by mistake, don't blow out candles or deepa (diya) as "candle-blower" (or it's equivalent in Sanskrit) is a derogatory term used for thieves - the idea is that before robbing a house a thief blows out the light source!
How to celebrate our birthday by Chaganti Koteswara Rao (YouTube video in Telugu)
How to Celebrate Birthday on Bhakthi TV's Dharma Sandehalu (YouTube video in Telugu)
Birthday is the day for enhancement of the ability of an embodied soul to imbibe chaitanya, through the benevolent frequencies gained by invoking Deities. Through this action which raises the sattva component in the atmosphere, the embodied soul achieves stability of the inner mind
In Satyayug, Tretayug (note) and Dwaparyug (Third in the cycle of the
four eras), spiritually evolved individuals were either invited to
bless the person on his first birthday, or the child would be taken to
such individuals for their blessings. The evolved individual would
perform aukshan (Ritual of waving a lit lamp in front of the
individual) of the child and, making an unexpressed resolve, would
shower akshata (Unbroken rice grains smeared with saffron and used in
ritualistic worship) on various parts of the child's body, thus
activating the chakras in those areas.
B. Birthday of a person in Tretayug and Dwaparyug Saints would assess
the spiritual progress of a person during the year and then bless
In Tretayug and Dwaparyug, several spiritually evolved individuals would visit a person and would bless it for rapid
spiritual progress or the person would visit Saints to seek their
blessings. After receiving blessings from the spiritually evolved, the
individual would make sincere efforts towards spiritual progress. On
the subsequent birthday, when the individual would go to seek the
blessings of a Saint, He would evaluate the spiritual progress made by
the person during the year and only then bless him.
Importance of celebrating the birthday as per the tithi A. Blessings and good wishes bestow maximum benefit
Our vibrations match the tithi of our birth most. As a result, the blessings and good wishes of relatives and well-wishers
are most effective on that tithi. Hence, the birthday should be
celebrated as per the tithi.
In according to Malayali Hindu families, birthday's are not celebrated using English calendar days, instead they celebrate it using birth star or Naalu or Nakshatra
which differ from year to year, and as you have said that 60th birthday (Shashti Poorthi) is celebrated very grandly and is usually celebrated of a male, in which it is considered that he has completed his half of his life as of 120 years of estimated normal Human life, in the same way 70th is also celebrated which is termed as Sapthathi which is not celebrated that grandly as the 60th one.
According to traditional Vedic astrology it is advised that the birthday should be celebrated as per the Hindu lunar calendar. Astrology birthday as per Hindu calendar is 'tithi' based. According to wikipedia - In vedic timekeeping, a Tithi (also spelled thithi) is a lunar day, or the time it takes for the longitudinal angle between the moon and the sun to increase by 12. Tithis begin at varying times of day and vary in duration from approximately 19 to approximately 26 hours. There are 30 tithis in each lunar month.
How important is the birthday celebration in Hinduism?
Hindus from ancient times have celebrated birthday based on tithi calendar. Recently we have slid away from our tradition by following birth days based on english calendar. Tithi is the traversal of 12 degrees between the moon and the sun. We know for a fact that the sun and moon have a great influence on our mind, hence it is accurate to be reminded of our human birth at that time of the year when the sun and moon form the same angle again i.e. the same tithi. Also this Indian calendar is the only continuous calender of our civilizations. You may know that the Julian and Gregorian calendars are based on a king and a pope (Gregory). In the 17th century there was an abrupt shift of 10days when the western world moved to the Gregorian from the Julian calendar. Thus all the birthdays that are celebrated before 17th century are anyway incorrect. Take an example of Shivaji Maharaj who was born on Phalgun Krishna Paksha Trithiya is celebrated on 19th Feb 1630 which is incorrect even by english calendar. Research Reference: www.tifr.res.in/~vahia/shivaji.pdf
Through the Indian calendar we can connect to our ancient civilization and traditions especially if you share your janmatithi with gods like Rama , Krishna or if it co-incides with hindu festival days.
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