I once hung out here in the Forums a fair amount when I first got involved with the Whole 30 and Paleo eating in general, back in mid 2017. I came back today for the first time in several years, and wanted to share my results as encouragement to anyone just starting the Whole 30, or considering it.
My first Whole 30 turned into an almost Whole 45, because two weeks in, I discovered two things I was eating somewhat regularly that had small amounts of added sugar (a jerk seasoning that I still use in my Food Freedom stage, and breakfast sausage (I still make my own breakfast sausage now.)) I decided that if I was going to do this, I was going to do it right.
After those 45 days, here's what happened to me:
I lost 40 pounds without increasing exercise or ever feeling hungry
My blood sugar went from pre-diabetic (and a doctor e-mailing me personally to let me know how serious it was) to completely normal. 5+ years later it is still completely normal (meant to include the fact that I had blood work done less than a week ago so any numbers mentioned are still accurate.)
I was able to get off of blood pressure medication, and my blood pressure was/is lower than it was on medication
Lifelong mild eczema disappeared
The inflammation in my arthritic ankle (old indoor volleyball injury) that hurt so bad I could not run, cleared up and I can still run - I ran up and down several flights of stairs this morning as part of my occasional "sprinting" routine
Triglyceride level decreased to a third of what they were
Mild improvement in sleep (my sleep wasn't bad, but it improved nonetheless)
A couple of additional comments, I am reaping all of the above benefits (with a few caveats below) 5+ years later. I NEVER feel deprived about my food choices - I am a pretty capable cook, and ALL spices, garlic, onions, fruit (think lemon/lime mostly), char from grilling/high temperature are allowed under the Whole 30 mindset. I have cooked many Whole 30 compliant dinners for friends that elicited comments like "you should open a restaurant". (Don't want to though ) About two years ago I got together for lunch with a friend that I hadn't seen in a couple of years, and ordered a salad with shrimp and a couple of substitutions to make it Whole 30-ish, and he remarked "you're still doing that diet?" - and my reply was "this is just how I eat now".
I promise that this can be a sustainable lifestyle - when I divert from my "ideal diet" once or twice, I rarely notice any ill effects. But I certainly notice the effects when I go from, say, 95% Whole 30 compliant to even 80% compliant. Recently I've been quite busy, and have substituted some fast food and other normally avoided foods (mostly grains and sugar), and I am seeing a little eczema creeping in, my ankle is sending me some mild pain signals (like I said, I did run on it this morning but cut it short since I could feel the inflammation.) Further testimony to the effectiveness of this approach.
Keep in mind that when I did my first Whole 30, I was 55 years old, obese, dangerously pre-diabetic, and had an incredibly crappy diet. It will be hard to match the gains I experienced if any of those are not true for you. But my point is, I have personal experience that the Whole 30 can be miraculous.
Give it an honest try. What do you have to lose, except (potentially) weight, blood sugar count, blood pressure measurements, skin inflammation, pain, triglycerides and insomnia?