…a very gentle, kind, intelligent soul.

Dr. Jeffrey Mark
I never knew a colonoscopy could be such a great experience until I met Dr. Mark and his staff. He was thorough, gentle and caring which made an uncomfortable procedure very pleasant and relaxing. I highly recommend Dr. Mark. ~ Elizabeth F. Buselli, NP, Ph.D.
I am a 55-year old female who has just had my second colonoscopy recently with Dr. Mark.
Dr. Mark and his staff have been wonderful and made the entire experience easy and comfortable.
If you have been putting off having the procedure due to working or concerns, please go ahead and trust Dr. Mark and his staff and go for it! They will take care of you, treat you with the utmost respect and sensitivity and you can feel safe that you don’t have to worry about colon cancer. ~ Missy Martin
We are grateful that he is in our lives.
Dr. Mark has been our Gastroenterologist since he opened his practice in Danville. We are extremely satisfied with Dr. Mark’s medical care and want to introduce him to others.
Other than being a wonderful physician, he is also very kind, conscientious, caring and with a bedside manner beyond reproach. We are grateful that he is in our lives. ~ Haig and Vula Rushdoony
Dr. Mark and nurses respected that I did not want sedation. Everything went great and I was able to be non-groggy and enjoy my grandson after the procedures. Thanks to all.
Everyone was very nice and I felt well cared for.
Dr. Mark made me feel at ease Thank you for taking care of me! This really exceeded my expectations!
I was in the very best of hands. Dr. Jeffrey Mark is also a very gentle, kind, intelligent soul. Thank you!
When my son was diagnosed with ADHD in 4th Grade, I took him to 6 different specialists who all just wanted to put my son on prescription drugs. He was unable to focus in school and was always getting in trouble with his teacher. I felt pressured by everyone to put him on medications but knew in my gut that is not what I wanted for him. I wanted a natural solution and that is precisely what I found with Dr. Mark who tested my son, and manage his ADHD with diet and supplements and other natural options. I’m happy to say that my child is now thriving in school and I know I found the best solution for my family. Thank you Dr. Mark. ~ S.Y. – A Danville patient
For the better part of my life I have suffered from acute anxiety. Recently personal circumstances caused my anxiety to skyrocket. I sought out Dr. Mark for a solution and sure enough he had a supplement that helps with anxiety. I had my doubts that a supplement could help because traditionally anxiety is treated with prescription drugs so I was certain a supplement would not help. I was ASTOUNDED that within 3-4 days my anxiety level had dropped to almost nothing. Today I’m anxiety free and feeling better than ever.
Thank you Dr. Mark and everyone at All Functional Health for providing the excellent products and services that keep us healthy. ~ A San Ramon Patient
A few years ago I first contacted Dr. Mark for a stomach virus that I couldn’t seem to get well from. Dr. Mark took the time to explain to me that my digestive system was likely compromised from the chemotherapy I had received a few years prior and started me on a 30 day plan to reset the bacteria levels in my stomach which chemotherapy damages. He prescribed a probiotic and two different powders to drink daily. Not only did this completely cure my stomach problems I felt better than I had in a long time. Dr. Mark explained that when our bacteria levels are correct we are able to better absorb the nutrients from food therefore we are better nourished and feel better overall. I still take the probiotics to this day and have never had any recurrence of stomach problems. I would like to take a moment to extend my appreciation to Dr. Mark and his office for helping me stay healthy. ~ Patti Z. – A cancer survivor patient
Dr. Jeffrey Mark suggested that I would benefit from doing his Detox Program in order to address a deficiency he noticed in my blood test. I did the”14-Day Detox”, taking the powder packets and supplementary capsules as directed, followed by another 7 days of the Bio-transform powder product. From the information booklet, I selected sauerkraut and raw cauliflower as my snack foods. No other snacks consumed.
I chose Dinner as my non-powder meal, having 5-6 ounces of Grass Fed Beef, plus vegetables (no starches, sugars, etc, per the instructions). No alcohol or caffeinated beverages. Filtered water only, as directed.I experienced no ill effects at all from the program, but after just a few days,I noticed I had dropped some weight. I started at 188 lbs, and finished at 174 lbs.
The powder drink tastes good to me, and I was very surprised at how comfortable I felt throughout the Detox Program in terms of NOT being hungry. I saw Dr. Mark a day after completion of the program, and was stunned to see my blood pressure had significantly dropped from a long term average around 120/85 to 85/65. That was amazing to me, and not an expected outcome. In 5 months or so, I will have my blood tested again to see if my numbers have improved further ….and check on my blood pressure, of course! Also, I am going to continue having the Bio transform Sugar Free and Stevia Free powder once daily for the long term, as I like it. It’s very economical on a per-meal-substitute basis, it’s a superb product nutritionally, it meets a specific protein/carb requirement that I can count on for one meal as a sort of “anchor” to help me be more mindful and disciplined about my daily “real” food intake. My goal is better weight maintenance and keeping my blood pressure down to my “new” safer level.
~ Bruce McKendry – 71 y.o. Age Management and Regenerative Medicine Patient