Expert Q&A

What do experts say about you prefer to do prolonged fasting (to induce autophagy) in the summer or winter?

Understanding Autophagy and Prolonged Fasting

Autophagy is your body’s cellular cleanup process that removes damaged proteins and organelles, becoming highly active during prolonged fasting periods of 24-72 hours. In my work with thousands of patients aged 45-54 struggling with hormonal changes and stubborn weight, I’ve found that timing these fasts with seasons can dramatically improve outcomes. This isn’t another fleeting diet trend—my methodology, outlined in The Metabolic Reset Protocol, emphasizes aligning fasting with your body’s natural rhythms to overcome the failures of past diets.

During prolonged fasting, insulin drops, growth hormone rises, and autophagy peaks around 24-48 hours. For those managing diabetes and blood pressure, this process helps improve insulin sensitivity by up to 30% in clinical observations, but only when done safely with medical supervision.

Why Winter May Be Optimal for Prolonged Fasting

Winter offers distinct advantages for inducing autophagy through prolonged fasting. Colder temperatures naturally elevate brown fat activity, which increases calorie burn by 15-20% and supports metabolic flexibility. Your body craves fewer carbohydrates in winter, making it easier to maintain the low-insulin state needed for deep autophagy.

Shorter daylight hours align with your circadian rhythm, promoting better melatonin production that enhances cellular repair. For those with joint pain, indoor winter fasting avoids summer heat exhaustion while allowing gentle movement like walking indoors. In my practice, patients report 2-4 pounds more visceral fat loss when doing 36-48 hour fasts between November and February compared to summer attempts.

Hormonal shifts are gentler too—cortisol doesn’t spike as dramatically in cold months, reducing the stress that often sabotages weight loss in perimenopausal women.

Summer Considerations and Potential Drawbacks

Summer fasting presents unique challenges. Higher temperatures increase dehydration risk during prolonged fasting, potentially stressing kidneys already taxed by blood pressure medications. Electrolyte imbalances occur 40% more frequently in heat, which can worsen joint pain and fatigue.

Longer daylight suppresses melatonin, potentially reducing autophagy efficiency by 25% according to chronobiology research. Social pressures—barbecues, vacations—make adherence harder, leading to the yo-yo effect many experience after failed diets. However, if you’re highly motivated, early summer (before peak heat) with careful hydration can still work, especially if combined with my recommended 16:8 intermittent fasting bridge days.

Practical Protocol for Seasonal Success

Start with winter for your first prolonged fasting experience. Begin with 24-hour fasts twice monthly, progressing to 36-48 hours as tolerance builds. Focus on bone broth and electrolytes on fasting days. Track blood glucose and ketones to confirm autophagy—beta-hydroxybutyrate levels above 1.0 mmol/L indicate strong cellular cleanup.

Regardless of season, consult your physician, especially with diabetes or blood pressure concerns. My approach prioritizes sustainability over extremes, helping middle-income families achieve results without expensive programs insurance won’t cover. By timing fasting to winter, you’ll likely experience less overwhelm, better energy, and the lasting metabolic reset that finally breaks the cycle of disappointment.

💬 What the Community Says

The community shows strong interest in seasonal timing for prolonged fasting but remains divided on summer versus winter. Many in their late 40s and early 50s report winter fasts feel more natural due to reduced appetite and easier indoor routines, with several noting better autophagy markers and 5-10 pound losses. Summer attempts often draw complaints about heat-induced headaches, dehydration, and social interference leading to broken fasts. A vocal group of experienced fasters argues summer works if you stay hydrated and use air conditioning, citing higher vitamin D levels as a plus for recovery. Beginners frequently express confusion from conflicting online advice, with joint pain sufferers overwhelmingly preferring winter to avoid summer exercise barriers. Overall, most practitioners seem to favor winter starts for autophagy induction, though a minority successfully rotates seasons based on personal energy levels and work schedules.
Clark, R. (2026). What do experts say about you prefer to do prolonged fasting (to induce autophag. *CFP Weight Loss*. https://ask.cfpweightloss.com/ask/what-do-experts-say-about-you-prefer-to-do-prolonged-fasting-to-induce-autophagy-in-the-summer-or-winter
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.

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
▸ What is a super quick "Mix some of this in" to make coconut oil (purely in liquid form) taste ok to make it easy to consume: how to talk to your doctor about this during the weight loss plateau phase? ▸ Low TSH, Low T4, and Low T3 simultaneously on Levothyroxine — anyone experienced this and the role of cortisol and stress hormones — what certified coaches recommend? ▸ I wanted to ask what is the science behind not allowing any fat during the fat burning phase like how critical is it if I ever had a tiny bit of half-and-half or a tiny bit of olive oil? Is it really do something to the body. ▸ If a random dance partner app existed .. would you try it: how to talk to your doctor about this and its effect on metabolism and insulin levels? 📖 Strategic Fat Loading — A critical 48-hour phase at the start of the reset where we prime the body with healthy fats to trigger the transition f… ▸ 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: best practices and common mistakes to avoid? ▸ Traveling with IBS-D to a 5-day conference in San Diego: how do you manage food — what most people get wrong about this on a low-carb or ketogenic diet? ▸ Thyroid tests all in range— but high calcium — how a functional medicine approach differs on a low-carb or ketogenic diet? ▸ Will eating meintenance calories make me lose weight for those with hypothyroidism or Hashimoto's when you have PCOS or hormonal imbalances? 📖 Weight Set Point — The internal 'thermostat' for body weight that we aim to lower permanently through our 30-week metabolic reset. ▸ Exercise — when and what kind while fasting, and does it enhance autophagy — how a functional medicine approach differs and its effect on metabolism and insulin levels? ▸ Good calorie amount? Advice to get high volume low cal and more protein when you have PCOS or hormonal imbalances 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 ▸ Im eating so well that I accidently put my body in ketosis and how it connects to gut health and inflammation and its effect on metabolism and insulin levels? ▸ Compression socks. Worth it? Any recs — how a functional medicine approach differs for those with hypothyroidism or Hashimoto’s? ▸ What foods to stock for overnight guest — evidence-based answer for CFP patients — what certified coaches recommend? ▸ Can autophagy regenerate muscle during physically active prolonged fast and how it connects to gut health and inflammation and its effect on metabolism and insulin levels? 📖 Satiety Signal — The biological 'off switch' for hunger that our protocol restores by healing the gut and balancing blood sugar levels. ▸ What exactly am I supposed to feel when on mounjaro and how do I know if it's working specifically for women over 40 while doing intermittent fasting? ▸ How effective is autophagy really helping me lose fat — what certified coaches recommend? ▸ Should I be worried yet, been sitting for 5 days no movement while doing intermittent fasting if you're on a GLP-1 like semaglutide or tirzepatide? 📖 High-Dose Dependency — The pharmaceutical trap of staying on maximum medication doses indefinitely, which we avoid through our smart cycling me… ▸ 78kg to 58kg for an 18 y/o: How likely am I to have loose skin after weight loss specifically for women over 40 — what certified coaches recommend? ▸ How does chasing skinny ever get old for long-term results while doing intermittent fasting? ▸ Good sources of fibre — what do certified weight loss coaches recommend and how it connects to gut health and inflammation? 📗 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 ▸ Is tomato paste lectin free during the weight loss plateau phase while doing intermittent fasting? ▸ Does mental health predict diabetes as much as BMI? Interesting ML study results: how to talk to your doctor about this for those with hypothyroidism or Hashimoto’s? ▸ Do you think they read the responses they receive: how to talk to your doctor about this while doing intermittent fasting? 📖 Amylopectin A — The specific starch found in modern wheat that causes rapid, dangerous spikes in blood glucose and promotes belly fat st… ▸ I am on my second week of mounjaro (2.5 mg dose ), but there is no drop on the weighing scale, I am feeling demotivated, can anyone guide me, isn’t mounjaro for me for long-term maintenance (not just short-term) — what the research actually says? ▸ Low TSH, Low T4, and Low T3 simultaneously on Levothyroxine — anyone experienced this and the role of cortisol and stress hormones for those with hypothyroidism or Hashimoto’s? ▸ What can I ask for if estrodiol cream remains in shortage? Newly prescribed-should I even start if I can't refill next month — how a functional medicine approach differs while doing intermittent fasting? ▸ Crust check 🔥 ribeye done right — what the research actually says? 📖 Cellular Detox — The process of clearing out metabolic waste and reducing cellular stress to allow for more efficient energy production a… ▸ These electrolyte tabs, how often — evidence-based answer for CFP patients specifically for women over 40? ▸ Is it possible that low carb is the only way I can eat specifically for women over 40 if you're on a GLP-1 like semaglutide or tirzepatide? ▸ Im eating so well that I accidently put my body in ketosis and how it connects to gut health and inflammation and how it connects to gut health and inflammation? 📗 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 ▸ The cost of meat is soaring, especially beef. What are y’all doing to stay on budget on a low-carb or ketogenic diet? ▸ I have an iodine deficiency. Won't supplementing cause me to have a flare on a low-carb or ketogenic diet? ▸ Omnipod. Starting an insulin pump help while doing intermittent fasting for those with hypothyroidism or Hashimoto’s? ▸ Diabetics with TPN (IV nutrition experience) and the role of cortisol and stress hormones on a low-carb or ketogenic diet? 📖 GIP (Gastric Inhibitory Polypeptide) — A hormone that, when combined with GLP-1, enhances the body’s ability to break down fat and manage blood sugar levels mo… ▸ Those of you with Reta experience how does this protocol look for people with insulin resistance when you have PCOS or hormonal imbalances? ▸ Exercise — when and what kind while fasting, and does it enhance autophagy — how a functional medicine approach differs specifically for women over 40? ▸ Omnipod. Starting an insulin pump help while doing intermittent fasting for long-term maintenance (not just short-term)? ▸ Why cant i lose weight and am gaining weight when you have PCOS or hormonal imbalances 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 ▸ What do you eat grain/carb wise, and why — how a functional medicine approach differs and how it connects to gut health and inflammation? 📖 Smart Cycling — The strategic alternating of medication doses with planned 'off' periods to prevent receptor desensitization and ensure … ▸ Is the carnivore diet the best WOE to lose weight — what does the research actually say specifically for women over 40? ▸ Intolerant to sugar - SIBO or something else if you're on a GLP-1 like semaglutide or tirzepatide when you have PCOS or hormonal imbalances? ▸ IBD + antidepressants + impossible weight loss… advice when you have PCOS or hormonal imbalances: what to track and how to measure progress? ▸ What to do if you have to eat late dinners?? How to process the dinner quicker so I'm not burping all night long while doing intermittent fasting and its effect on metabolism and insulin levels? ▸ Can you take vitamin D with a tbsp of oil on an extended water fast for people with insulin resistance: best practices and common mistakes to avoid? ▸ LDN is changing my life, will this last: best practices and common mistakes to avoid for people with insulin resistance? 📖 Bio-Individuality — The understanding that every patient’s metabolic journey is unique, requiring a personalized approach to dosing and diet… ▸ What’s your favorite toothpaste for people with insulin resistance for long-term maintenance (not just short-term)? 📗 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 ▸ Sugar free 2020, who's with me — what most people get wrong about this: what to track and how to measure progress? ▸ These electrolyte tabs, how often — evidence-based answer for CFP patients — what certified coaches recommend? ▸ How I Lost 22lbs in 3 Months (155→133lbs at 5'8") after not being able to lose weight for a long time if you're on a GLP-1 like semaglutide or tirzepatide during the weight loss plateau phase? ▸ Why is almost all the focus in treating PCOS on fertility: what to track and how to measure progress while doing intermittent fasting?