I'm not a patient of Dr. Gundry, but I did meet him last summer at the Boulder gathering, and was mightily impressed. He went to the other lectures, went to dinner with the apoe4.info group where he ate his own diet and answered questions at length. He answered my casual questions at length as well, cogently and with the data that comes from experience. He was charging $500/hour for phone consults at the time, so I felt that I got thousands of dollars of great advice for free. This hardly seems to be the modus operandi of a money-seeking quack!
Often physicians of my acquaintance, when asking why I look better, go off on a rant when I talk about diet and supplements - usually about double-blind experiments and the like. They are mostly not in very good shape, and would probably kill for my blood work! fwiw, in three months on Gundry my total cholesterol dropped 40 points to around 150 in both NMR and standard measure, and my HDL > LDL > TG. Uric acid down, homocysteine way down, kidney function up, HbA1c down a lot to 5.2.
I think the question that must be asked, by the most skeptical and scientific among us, is who are you going to trust - a practitioner with a lifetime of experience including a couple of decades pushing a patient regimen of nutrition and bloodwork which is very effective; or some expensive double-blind lab tests, where you have to ask 1) who paid for them and 1a) why did they get done, as opposed to some other expensive test; and 2) does the test design actually translate into real knowledge, or does it confound different variables - kinds of carbs, fats, etc.
As for me, I'll take the practitioner any day! Someone who deals with real people, and can say with assurance, "We have seen this many times, and what works is to ........." When this is bolstered by popular support - people who have been cured or had their lives vastly improved do tell their friends and families! - then you would seem to have the best of all possible worlds. (And negative publicity also spreads very quickly, especially today.)
Gundry has passed up the opportunity to do hundreds, if not thousands, of very lucrative surgeries. How many hundreds of jars of Vital Reds would he have to sell to make up for just one surgical fee?! I honestly believe that he must regret his choices financially to some degree. If he thus decided to literally bottle what he knows and recommends for the good of his patients in order to level the playing field as it were, how is this a bad thing? Money-back guarantee, and he's been working a long time outside the big medicine/surgery field because he thinks he can do better with a natural result?? Who here would prefer to go to a random cardiologist with their issues, and be treated to the usual invasive surgeries and pointless dietary advice, in exchange for a lot of money? Given the typical results, who are the actual "quacks" here?