In the LDS faith, they follow a law of health called the Word of Wisdom that teaches them to abstain from things like alcohol and tobacco and it encourages them to eat foods like grains, fruits, and vegetables.
How has the Word of Wisdom changed since its introduction compared to what it is today?
The revelation known as the Word of Wisdom is set forth in section 89 of the Doctrine and Covenants. It speaks of basic dietary and health principles, listing substances that are harmful and should be avoided (mainly addictive drugs) and positive things that should be observed (a healthy diet), and promises blessings of health, strength, knowledge and spiritual deliverance to those who observe its principles.
The only substantial change in doctrine between when the Word of Wisdom was first given and modern times is that it was originally given:
2 To be sent greeting; not by commandment or constraint, but by revelation and the word of wisdom, showing forth the order and will of God in the temporal salvation of all saints in the last days—
3 Given for a principle with promise, adapted to the capacity of the weak and the weakest of all saints, who are or can be called saints.
whereas today it is considered a commandment to the members of the church. This change was adopted in a general conference of the church in 1851, almost 20 years after the original revelation was given, under the reasoning that it would have been impractical to ask the general population of the church, many of whom were already accustomed to using substances known to be addictive, to give them up all at once, but that by this time they had had plenty of time to phase out the use of such things.
Today, observance of the Word of Wisdom is necessary before a person investigating the church can be baptized, and continued observance is required for a member to be considered worthy to go to the temple.
The the Word of Wisdom was originally given as a revelation to Joseph Smith and recorded in Doctrine and Covenants 89:
That inasmuch as any man drinketh wine or strong drink among you, behold it is not good...And again, tobacco is not for the body, neither for the belly...And again, hot drinks are not for the body or belly...And again, verily I say unto you, all wholesome herbs God hath ordained for the constitution, nature, and use of man...Yea, flesh also of beasts and of the fowls of the air, I, the Lord, have ordained for the use of man with thanksgiving; nevertheless they are to be used sparingly...All grain is good for the food of man; as also the fruit of the vine; that which yieldeth fruit, whether in the ground or above the ground...
At various times, some Mormons have interpreted the Word of Wisdom in different ways; here I mention only official changes.
Became a commandment
When it was first revealed (1833), the Word of Wisdom was "a principle of promise" but not a commandment.
...not by commandment or constraint, but by revelation and the word of wisdom...for a principle with promise, adapted to the capacity of the weak and the weakest of all saints, who are or can be called saints.
Doctrine and Covenants 89:2-3
The items prohibited by the Word of Wisdom were in common use, with little known about adverse health effects. The Saints (even the "weakest") were given time to adjust. It later became a commandment.
September 9, 1851, President Brigham Young stated that the members of the Church had had sufficient time to be taught the import of this revelation and that henceforth it was to be considered a divine commandment.
Joseph Fielding Smith, Answers to Gospel Questions, Vol 1. Chapter 48
Adherence to the Word of Wisdom was made a requirement for temple admission in 1902, and remains that way today.
Hot drinks
This is really not a change but a clarification.
"Hot drinks" meant the drinks that were customarily drunk hot at that time: tea and coffee. This was made explicit soon after the original revelation, for example, by the Presiding Patriarch Hyrum Smith:
And again "hot drinks are not for the body, or belly;" there are many who wonder what this can mean; whether it refers to tea, or coffee, or not. I say it does refer to tea, and coffee.
Times and Seasons (June 1, 1842)
Illegal drugs and harmful substances
In modern times, the Church of Jesus Christ of Latter-Day Saints has added the following statement to the official description of the Word of Wisdom:
Members should not use any substance that contains illegal drugs. Nor should members use harmful or habit-forming substances except under the care of a competent physician.
