You have a pretty good handle on the Word of Wisdom, but just in case, here it is in the original form:
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. (Doctrine and Covenants | Section 89:1 – 21)
This was given to Joseph in February of 1833 in answer to his prayer about the general use of tobacco and coffee and tea among the early LDS members. It was new then and the Lord surely knew the difficulty of commanding those early members to go cold turkey at that time.
Later it was revealed that is should become a “law of health” adding harmful drugs to the list of things to avoid. It then became an important matter enough to be a requirement to enter the temple to make the sacred covenants and promises that are offered there. I don’t expect anyone, not of our faith, to really understand, but to me, it is as much a measure of ones faith and readiness to commit to the promises made in the temple to follow Jesus Christ and live his gospel as it is about our health as it has a spiritual benefits for those who are abiding by it. For sure, members of our faith are shown to be healthier and live longer when they live the Word of Wisdom than the general population.
I am not sure you are correct in saying that some soda drinks have less caffeine than coffee or tea. I have heard otherwise, but health experts are not all that positive about the consumption of those commonly used drinks. Surely being overweight is not healthy, but as I said, however, there is more to keeping the word of wisdom than just physical health.
I am very glad that I believe in and have tried to live by the Word of Wisdom. I can tell you that it has been a great blessing to me, especially as I look around and see what has happened to a good percentage of my fellow performers as it relates to the use and abuse of substances that are so very destructive, most of which begins with alcohol leading to harmful drugs.
I hope this answers your question.