I have an even simpler explanation : They're both caused by eating.
More seriously, yes, I agree that sugar is nasty, but it's a bit too simple to blame it as the sole factor for all possible diseases that have a mechanism of action that hasn't been clearly identified.
Of course not ! Even for proven health benefits, I would probably refuse that, not only from my boss, of course, but from anyone. This feels very wrong on so many levels.
Okay, we're in an existential and metaphysical (meaning of Life) thread. Please let me give you a metaphysical and seemingly irrational answer. Irrational doesn't prevent truth, btw. So here it is : I gave my life away to God (and try to remember doing it every day), because I realized at some point that I cannot make it meaningful nor make it meet my requirements. What happened is that He transformed me (and still does). Think of it (if you can) : God is your creator. He knows you better than yourself. He knows why you were created. He's allowing this world to stay alive, not to prolong suffering, but so that everyone can be with Him, well and alive, for now and for eternity. He loves (i.e. wants the best for someone) each one of us in the strongest way. What proof do I have for this statement ? Well, I found that in the Bible (the most read book in the world). Every day, I'm getting better (still suffering, of course, but for a reason) in this crazy world : It's not a psychological crutch, it's a real relationship with someone, who happens to be the best possible and most loving person. How does it work ? Forget your pride. You pray (i.e. talk to your creator, in all honesty), He answers. Also, you read the Bible, you get answers. Guaranteed (by God himself).
PS : There are free & offline apps to read the Bible.