Expert Q&A

Benefits of extended fasting: how to talk to your doctor about this

Understanding Extended Fasting and Its Core Benefits

I've seen thousands in their 40s and 50s finally break through stubborn weight after years of failed diets. Extended fasting—typically water-only fasts lasting 48 to 72 hours or longer—triggers powerful metabolic shifts. It lowers insulin levels dramatically, allowing your body to burn stored fat for fuel. Clinical observations show average losses of 0.5 to 1 pound per day, much of it visceral fat that contributes to high blood pressure and diabetes.

Beyond weight, extended fasting promotes autophagy, your cells' natural cleanup process that peaks around 24-48 hours. This reduces inflammation linked to joint pain, making movement easier even for those who find exercise impossible. Many of my clients report improved blood sugar stability within days, often needing less medication under medical supervision. Hormonal changes in perimenopause and menopause respond particularly well because fasting helps regulate cortisol and insulin, two hormones that make fat loss feel impossible.

Preparing for the Conversation with Your Doctor

Insurance rarely covers weight loss programs, so you must approach your physician as an informed partner. Start by scheduling a dedicated visit rather than squeezing it into a 10-minute checkup. Bring recent labs showing your A1C, fasting glucose, CRP for inflammation, and lipid panel. Explain your history of diet failures and how joint pain limits traditional exercise.

Use clear language: "I've read about the metabolic benefits of extended fasting in medical literature and want to explore it safely under your guidance, especially given my diabetes and blood pressure." Share specific goals like lowering your A1C by 1.5 points or reducing joint inflammation enough to walk 30 minutes daily. Mention you're following principles from my book where we combine strategic fasting windows with nutrient-dense refeeding to protect muscle mass.

Key Questions to Ask and Safety Protocols

Come prepared with questions: How will my medications need adjusting during the fast? What electrolyte protocol should I follow to prevent imbalances? Can we monitor my blood pressure and glucose daily? Doctors respond best to patients who acknowledge risks—dehydration, electrolyte shifts, or hypoglycemia—while demonstrating knowledge of proper hydration with salt, magnesium, and potassium.

In my methodology, we never recommend jumping into 72-hour fasts. Beginners start with 16:8 time-restricted eating, progress to 24-36 hour fasts, then extend under supervision. Track ketones with inexpensive strips to confirm you're in therapeutic fat-burning range (0.5-3.0 mmol/L). Re-feeding with bone broth and easily digested proteins prevents refeeding syndrome.

Realistic Outcomes and Building Long-Term Success

Extended fasting isn't a magic cure but a tool that resets metabolic flexibility. Clients combining it with my simple meal plans—high protein, moderate fat, low processed carbs—see sustainable 15-25 pound losses in 90 days without overwhelming schedules. The embarrassment of asking for obesity help fades when you present data and a clear plan. Remember, your doctor’s job is risk management; your job is advocating for this evidence-based approach that addresses the exact pain points of hormonal weight gain and diet fatigue.

💬 What the Community Says

The community shows cautious interest in extended fasting but remains divided on discussing it with doctors. Many in the 45-55 age group share stories of finally losing weight after multiple diet failures, especially when joint pain made regular exercise unbearable. Most practitioners report positive blood sugar improvements and lower inflammation, yet a vocal minority warns about medication interactions with diabetes and blood pressure drugs. Newcomers often feel embarrassed bringing it up, fearing judgment, while experienced fasters recommend bringing lab results and starting small. Insurance concerns surface frequently, with users noting doctors are more receptive when patients frame fasting as a short-term metabolic reset rather than a lifestyle. Overall sentiment is optimistic but emphasizes medical supervision and gradual progression to avoid negative side effects.
Cite this answer
Clark, R. (2026). Benefits of extended fasting: how to talk to your doctor about this. *CFP Weight Loss*. https://ask.cfpweightloss.com/ask/benefits-of-extended-fasting-how-to-talk-to-your-doctor-about-this
Russell Clark, FNP-C, APRN, FNP-C, APRN
About the Author

Russell Clark, FNP-C, APRN, is the founder of CFP Weight Loss in Nashville and CFP Fit Now telehealth. Over 35 years in healthcare — Army Nurse Reserves, Level 1 trauma ER, hospitalist — he developed a 30-week protocol integrating real foods, detox, and low-dose tirzepatide cycling that has helped hundreds of patients lose 30–90 pounds. He and his wife Anne-Marie lost a combined 275 pounds using the same protocol.

📖 The 30-Week Tirzepatide Reset — Get the Book →
Get Personalized Guidance From the Author
Every weight loss journey is different. Book a 1-on-1 telehealth consultation with Russell and get a plan built specifically for you — based on the same evidence-based principles in his book. Available to patients in all 50 states.
Book Your Consultation →
Have a follow-up question?
More Questions 200 answered
▸ Is it normal to lose 6 kg in one week during the weight loss plateau phase while doing intermittent fasting? ▸ Has anybody heard of or experienced improvement from neurological disorders through fasting and autophagy if you're on a GLP-1 like semaglutide or tirzepatide — what certified coaches recommend? ▸ What surprised me the most in menopause? Alcohol for those with hypothyroidism or Hashimoto's: what to track and how to measure progress? 📖 The Clark Protocol — Our evidence-based framework that combines clinical nurse practitioner expertise with personal experience to solve the o… ▸ When do you know to go to the hospital — evidence-based answer for CFP patients specifically for women over 40? ▸ Can you really Metformin (6 weeks in) for insulin resistance — can the gut stuff actually get better while doing intermittent fasting? ▸ How do you handle social settings and conversations with other people — what does the research actually say: best practices and common mistakes to avoid? ▸ Those of you with Reta experience how does this protocol look for people with insulin resistance if you're on a GLP-1 like semaglutide or tirzepatide? ▸ I sometimes feel like people only talk about the obvious symptoms like irregular periods or weight gain, but the fatigue can be just as overwhelming. Has anyone else felt completely drained even: how to talk to your doctor about this: what to track and how to measure progress? 📖 Bio-Individuality — The understanding that every patient’s metabolic journey is unique, requiring a personalized approach to dosing and diet… 📗 The 30-Week Tirzepatide Reset — by Russell Clark, FNP-C, APRN · The complete clinical protocol — 30 weeks of real foods, detox, and low-dose tirzepatide cycling that has helped hundreds of patients lose 3 ▸ What are some things you loved from your childhood that you (virtually) never see/experience anymore during the weight loss plateau phase — what the research actually says? ▸ Difference between a 3 day and 5 day water fast for autophagy and the role of cortisol and stress hormones while doing intermittent fasting? ▸ HOW TO DO AN AGGRESSIVE CUT WITH A STRESSFUL LIFESTYLE on a low-carb or ketogenic diet: best practices and common mistakes to avoid? ▸ Is it okay for teenagers to do longterm lowcarb/keto — evidence-based answer for CFP patients if you're on a GLP-1 like semaglutide or tirzepatide? ▸ Pic in the white tank top is when I first started 23 days ago, I weighed 280 lbs, compared to today, 269 lbs. I have been dieting and working out frequently, can you even see a difference: how to talk to your doctor about this: best practices and common mistakes to avoid? ▸ What a difference a year makes 🥰 during the weight loss plateau phase? ▸ Insulin resistance caused my weight gain despite eating low calorie diet, anyone else when you have PCOS or hormonal imbalances — what the research actually says? 📖 Adipose Tissue Signaling — The way fat cells communicate with the brain; our goal is to fix these signals so the body stops defending an unnaturall… ▸ Is Emma Relief good for gut issues and the role of cortisol and stress hormones — what the research actually says? ▸ When the symptom you went to the ER for clears up while you're waiting to be seen for people with insulin resistance on a low-carb or ketogenic diet? ▸ Anyone remember the metal lid you had to use a butter knife to pop off: what to track and how to measure progress specifically for women over 40? 📗 The 30-Week Tirzepatide Reset — by Russell Clark, FNP-C, APRN · The complete clinical protocol — 30 weeks of real foods, detox, and low-dose tirzepatide cycling that has helped hundreds of patients lose 3 ▸ For those who've lost the weight and kept it off... did you ever achieve true food freedom on a low-carb or ketogenic diet during the weight loss plateau phase? ▸ Can autophagy regenerate muscle during physically active prolonged fast and how it connects to gut health and inflammation: what to track and how to measure progress? ▸ Are people who get no effect just using bad product: best practices and common mistakes to avoid: best practices and common mistakes to avoid? 📖 Inflammatory Markers — Clinical indicators like CRP that we monitor to ensure the body is moving from a state of disease to a state of vibrant … ▸ How long until I start losing weight this way — how a functional medicine approach differs: best practices and common mistakes to avoid? ▸ Could Nanotyrannus be a nest parasite specifically targeting Trex during the weight loss plateau phase? ▸ Has anybody heard of or experienced improvement from neurological disorders through fasting and autophagy if you're on a GLP-1 like semaglutide or tirzepatide: what to track and how to measure progress? 📖 Gut Microbiome Repair — The restoration of healthy intestinal bacteria through the removal of lectins and grains, essential for long-term weight… ▸ Will eating meintenance calories make me lose weight for those with hypothyroidism or Hashimoto's on a low-carb or ketogenic diet? ▸ What is a ‘normal’ value for dawn phenomena for you for people with insulin resistance for those with hypothyroidism or Hashimoto’s? 📗 The 30-Week Tirzepatide Reset — by Russell Clark, FNP-C, APRN · The complete clinical protocol — 30 weeks of real foods, detox, and low-dose tirzepatide cycling that has helped hundreds of patients lose 3 ▸ Can I just skip the broth — how a functional medicine approach differs: what to track and how to measure progress? ▸ What are some tricks or tips to avoid snacking and how it connects to gut health and inflammation — what the research actually says? ▸ Does salt instantly relieve a slight headache for you if you're on a GLP-1 like semaglutide or tirzepatide for people with insulin resistance? 📖 Leptin Sensitivity — Restoring your brain's ability to hear the 'I am full' signal, which is often muted by high-sugar diets and systemic inf… ▸ Is compounded semaglutide with B12 worth choosing over B6 or plain: best practices and common mistakes to avoid when you have PCOS or hormonal imbalances? ▸ What actually helps with the dryness when you have PCOS or hormonal imbalances if you're on a GLP-1 like semaglutide or tirzepatide? ▸ When do you know to go to the hospital — evidence-based answer for CFP patients when you have PCOS or hormonal imbalances? ▸ LDN is changing my life, will this last: best practices and common mistakes to avoid specifically for women over 40? 📖 Metabolic Efficiency — The state where your body processes fuel cleanly and maintains high energy levels without the need for constant snacking… ▸ What if you are/were someone who eats even when full/not hungry on a low-carb or ketogenic diet while doing intermittent fasting? 📗 The 30-Week Tirzepatide Reset — by Russell Clark, FNP-C, APRN · The complete clinical protocol — 30 weeks of real foods, detox, and low-dose tirzepatide cycling that has helped hundreds of patients lose 3 ▸ Finally connected the dots between my thyroid, gut issues, and brain fog - why don't doctors look at the whole picture specifically for women over 40 and its effect on metabolism and insulin levels? ▸ Why is almost all the focus in treating PCOS on fertility: what to track and how to measure progress specifically for women over 40? ▸ To what extent do Mendelian Randomization Studies provide causal evidence for a particular claim — what do certified weight loss coaches recommend: best practices and common mistakes to avoid? ▸ 56M arm day was fun. But arms shrinking from 16 inches to 15 1/2. Gotta up protein? Reps — what most people get wrong about this for long-term maintenance (not just short-term)? ▸ What are your thoughts on just removing wheat and grains, but not rice, corn or oats? Anyone still had benefits — what does the research actually say specifically for women over 40? 📖 Hashimoto’s Success — Achieving weight loss and reduced inflammation in thyroid patients by removing dietary triggers like lectins and modern … ▸ Metformin (6 weeks in) for insulin resistance — can the gut stuff actually get better during the weight loss plateau phase? ▸ Starting a 7 day water fast, any tips to keep hydrated on a low-carb or ketogenic diet — what the research actually says? ▸ Do you think they read the responses they receive: how to talk to your doctor about this — what the research actually says? 📗 The 30-Week Tirzepatide Reset — by Russell Clark, FNP-C, APRN · The complete clinical protocol — 30 weeks of real foods, detox, and low-dose tirzepatide cycling that has helped hundreds of patients lose 3 ▸ Could Nanotyrannus be a nest parasite specifically targeting Trex: what to track and how to measure progress? ▸ Can i Fast for autophagy for loose skin without losing anymore weight — how a functional medicine approach differs for those with hypothyroidism or Hashimoto’s? ▸ Anyone know where to purchase pork rind tortillas — what do certified weight loss coaches recommend if you're on a GLP-1 like semaglutide or tirzepatide? 📖 Rebound Weight Gain — The common 'yo-yo' effect caused by high-dose, continuous GLP-1 use; we prevent this through strategic cycling and metab… ▸ Probiotics worked for a month then stopped. Anyone else for those with hypothyroidism or Hashimoto's if you're on a GLP-1 like semaglutide or tirzepatide? ▸ Are people who get no effect just using bad product: best practices and common mistakes to avoid: what to track and how to measure progress? ▸ How long does it take to Is Autophagy? 8 Amazing Benefits Of Fasting That Will Save Your Life while doing intermittent fasting? ▸ Does autophogy start sooner if following a keto diet before a fast and the role of cortisol and stress hormones: best practices and common mistakes to avoid? ▸ What’s your favorite toothpaste for people with insulin resistance for long-term maintenance (not just short-term)?