Most Active Mormons that hold a current temple recommend that allows them to enter their sacred Temples do not drink coffee and feel it is an important part of living The Word of Wisdom as found in Doctrine and Covenants Section 89 of their modern revelation scriptures. *
Now to the question as to whether it is a sin or not. Many Mormons will answer that it is a sin and you should not do it. Other Mormons will refer to the exact verbiage which says only “Hot Drinks” so they say it can be any hot drink and some say that means you could drink cold coffee. Others will refer to you clarifications that modern Mormon Prophets have made where they pointed out specifically that Coffee and Green and Black Tea should be avoided.
Ok, obviously the Mormon or LDS (Church of Jesus Christ of Latter Day Saints) Word of Wisdom does not apply to those that are not of their faith so anyone that is not a Mormon is not sinning when they drink coffee or tea.
Even within the LDS Church people will interpret the Word of Wisdom differently than others. When members are asked the questions for their Temple Recommend Interview they only ask “Are you living The Word of Wisdom” The answer is either yes, no or sometimes “I’m Striving to live it”.
So Mormons that have been through the Mormon Temples have made additional promises in those temples to God and to their spouses so they are held to a bit of a higher standard. This puts pressure on Mormons and even stresses many of them out.
Other Christians get the idea that Mormons think they can earn their way to heaven instead of having the grace of Jesus which is not true but misconceptions abound anyway.
Coffee has been researched and written about for many years and you will find articles that point out positive aspects of coffee and others that point out the dangers of coffee or too much of it.
What is harder for many Mormons to live and what gets ignored may be the things that are not spelled out exactly in The Word of Wisdom. When President Hinkley a former LDS Prophet was asked on National TV if he drank coke he said no that he did not and many members then took that to mean that they should not drink coke or any cola beverage. The Word of Wisdom is asking and suggesting to us that we be wise and prudent. Obviously when you take anything into your body that harms it that would in essence not following The Word of Wisdom. Many will try to justify drinking their soda and that is ok but when they weigh over 300 lbs justification does not really matter.
The Word of Wisdom also speaks of what you should eat and many Mormons ignore those words of advice and they focus on other more overt things such as “Not Smoking”.
In reality many Mormons choose not to obey their own Word of Wisdom so you will find Mormons that Smoke, Drink beer and such but those Mormons who strive to live the Word of Wisdom really do try to avoid harmful substances as outlined in the revelation.
So my answer: If a Catholic is drinking coffee no it is not a sin. If a doctor is smoking is it is a sin? An educated man that does something he knows is bad for him is unwise. That is the difference between knowledge and wisdom. I would classify this more as stupid behavior than I would sin.
If a Mormon that has made promises not to drink coffee is drinking coffee then rather than saying it is a sin I would lean toward saying he or she is holding themselves back from what they could be.
When you have a healthy body and a clean mind you are more apt to hear the Spirit of the Lord. He can direct you and help you be inspired to help others and yourself. When you cloud your mind with beer or other drugs you are less apt to hear that Spirit of the Lord and many times even less likely to follow the promptings of the Spirit.
*Doctrine and Covenants : 1 A Word of Wisdom, for the benefit of the council of high priests, assembled in Kirtland, and the church, and also the saints in Zion—
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.
4 Behold, verily, thus saith the Lord unto you: In consequence of evils and designs which do and will exist in the hearts of conspiring men in the last days, I have warned you, and forewarn you, by giving unto you this word of wisdom by revelation—
5 That inasmuch as any man drinketh wine or strong drink among you, behold it is not good, neither meet in the sight of your Father, only in assembling yourselves together to offer up your sacraments before him.
6 And, behold, this should be wine, yea, pure wine of the grape of the vine, of your own make.
7 And, again, strong drinks are not for the belly, but for the washing of your bodies.
8 And again, tobacco is not for the body, neither for the belly, and is not good for man, but is an herb for bruises and all sick cattle, to be used with judgment and skill.
9 And again, hot drinks are not for the body or belly.
10 And again, verily I say unto you, all wholesome herbs God hath ordained for the constitution, nature, and use of man—
11 Every herb in the season thereof, and every fruit in the season thereof; all these to be used with prudence and thanksgiving.
12 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;
13 And it is pleasing unto me that they should not be used, only in times of winter, or of cold, or famine.
14 All grain is ordained for the use of man and of beasts, to be the staff of life, not only for man but for the beasts of the field, and the fowls of heaven, and all wild animals that run or creep on the earth;
15 And these hath God made for the use of man only in times of famine and excess of hunger.
16 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—
17 Nevertheless, wheat for man, and corn for the ox, and oats for the horse, and rye for the fowls and for swine, and for all beasts of the field, and barley for all useful animals, and for mild drinks, as also other grain.
18 And all saints who remember to keep and do these sayings, walking in obedience to the commandments, shall receive health in their navel and marrow to their bones;
19 And shall find wisdom and great treasures of knowledge, even hidden treasures;
20 And shall run and not be weary, and shall walk and not faint.
21 And I, the Lord, give unto them a promise, that the destroying angel shall pass by them, as the children of Israel, and not slay them. Amen.