Expert Q&A

Should I continue my fast or no and its effect on metabolism and insulin levels

Understanding Fasting's Impact on Insulin Levels

As the founder of CFP Weight Loss and author of The CFP Method, I've helped thousands of adults aged 45-54 navigate weight loss despite hormonal shifts, joint pain, and prior diet failures. When it comes to whether you should continue your fast, the key lies in how fasting influences your insulin levels.

After 12-16 hours without food, insulin drops significantly—often by 50% or more—allowing your body to access stored fat for energy. This process, called lipolysis, is particularly beneficial if you're managing diabetes or blood pressure alongside obesity. In my CFP Method, we emphasize starting with 14-hour overnight fasts to gently lower insulin without overwhelming your system. For middle-income families with busy schedules, this requires no expensive programs or complex plans—just consistent timing.

How Fasting Affects Your Metabolism

Many fear fasting slows metabolism, but research shows short-term fasts (16-24 hours) can actually increase metabolic rate by 3-14% through elevated norepinephrine. However, extended fasts beyond 48 hours without proper refeeding may reduce thyroid output and basal metabolic rate by up to 15%, especially in women experiencing perimenopause.

In The CFP Method, we recommend cycling fasts—16:8 most days, with two non-fasting days weekly—to preserve muscle and keep metabolism humming. This approach has helped clients lose 20-40 pounds while reducing joint pain, as lower insulin decreases inflammation. If you've failed every diet before, know that metabolic adaptation is why; our method counters it with strategic protein intake (1.2g per kg body weight) on eating windows.

Deciding Whether to Continue Your Fast

Listen to your body. Continue if you feel energized, experience stable blood sugar, and have no dizziness after 16 hours. Stop and eat a balanced meal with protein and healthy fats if you feel weak, irritable, or overly hungry—these signal cortisol spikes that can worsen hormonal weight gain. For beginners overwhelmed by conflicting advice, track your fasting with a simple app and aim for consistency over perfection. Insurance rarely covers these programs, so our at-home CFP approach focuses on sustainable changes that fit your life without gym schedules.

Practical Tips to Optimize Fasting Results

Break your fast with bone broth or a small protein meal to ease digestion. Stay hydrated with electrolytes—sodium, potassium, magnesium—to combat fatigue common in this age group. Combine with gentle movement like walking to ease joint pain; even 20 minutes daily boosts insulin sensitivity by 25%. In my experience, clients who pair fasting with stress management see the best long-term success, dropping both weight and A1C levels. Start small, build confidence, and remember: this isn't another failed diet—it's a metabolic reset tailored for real life.

💬 What the Community Says

The community shows mixed but cautiously optimistic experiences with fasting for weight loss after 45. Many in online forums report improved energy and lower blood sugar after adopting 16:8 intermittent fasting, especially those managing diabetes or high blood pressure. A common theme is initial success followed by plateaus, leading some to question if metabolism slows with prolonged use. Beginners often share embarrassment about obesity and relief finding simple schedules that don't require expensive programs or intense exercise that aggravates joint pain. There's debate around hormonal changes in women, with some noting better results when adding strength training or cycling fasting days. A vocal minority warns against extended fasts without medical guidance, citing fatigue or hair loss, while most practitioners emphasize listening to the body and combining fasting with protein-rich refeeds. Overall, lived experiences highlight that consistency beats perfection, though conflicting nutrition advice leaves many feeling overwhelmed at the start.
Cite this answer
Clark, R. (2026). Should I continue my fast or no and its effect on metabolism and insulin levels. *CFP Weight Loss*. https://ask.cfpweightloss.com/ask/should-i-continue-my-fast-or-no-and-its-effect-on-metabolism-and-insulin-levels
Russell Clark, 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 →
Have a follow-up question?
More Questions 200 answered
▸ Should Endotoxin be the norm from vendors along with COA’s — what does the research actually say? ▸ Did anyone else feel like Trintellix completely blunted their GLP-1 (Mounjaro/Wegovy) effect: best practices and common mistakes to avoid ▸ Estradiol Cypionate- I’ve been underdosing- what dose are you at — what do certified weight loss coaches recommend? ▸ When period stopped did you feel like the worst pmdd of all time daily or on a low-carb or ketogenic diet ▸ POLL At what strength did Semaglutide become effective for you on a low-carb or ketogenic diet ▸ What garmin watch should i get for christmas specifically for women over 40 ▸ Can we stop posting good glucose levels and pretending they are bad: how to talk to your doctor about this 📖 The Clark Protocol — Our evidence-based framework that combines clinical nurse practitioner expertise with personal experience to solve the o… ▸ 2.5 mg no longer working. Move to 3.5 for long-term maintenance (not just short-term) 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → ▸ When people ask how I can tell my sugar's low and the role of cortisol and stress hormones ▸ Am I better off increasing my frequency of sessions per week, or my duration of each session — what does the research actually say? ▸ Can we stop posting good glucose levels and pretending they are bad — what does the research actually say? ▸ Has anyone been diagnosed with Hashimotos after going through emotional distress or chronic stress in general: best practices and common mistakes to avoid ▸ Are people fear mongering when they say compound pharmacies are dangerous and the role of cortisol and stress hormones 📖 Gut-Brain Axis — The complex communication network between your digestive system and your brain that controls satiety, mood, and metaboli… ▸ How much are people paying for Estring: how to talk to your doctor about this ▸ Cool, happy energy after upping estrogen patch specifically for women over 40 ▸ Any women here that never had a flat stomach in their lives during the weight loss plateau phase 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → ▸ Are people fear mongering when they say compound pharmacies are dangerous: best practices and common mistakes to avoid ▸ A Switch from HRT to Birth Control for those with hypothyroidism or Hashimoto's 📖 Satiety Signal — The biological 'off switch' for hunger that our protocol restores by healing the gut and balancing blood sugar levels. ▸ Can we talk about the founder: how to talk to your doctor about this ▸ How it looks when you lose 170 lbs. but are still a fat man — what most people get wrong about this ▸ Sanity Check: Is MyNetDiary accurate? ▸ How I feel every time I go grocery shopping for those with hypothyroidism or Hashimoto's 📖 Autophagy — The body's natural 'housecleaning' process that occurs during fasting or low-insulin states, promoted during our mainten… ▸ Should i really be aiming for 45 zone 2 minutes per day for fat loss and the role of cortisol and stress hormones ▸ Feeling fatter once having started my restrictive diet? ▸ Anyone use an auto injector for the compounded med — what most people get wrong about this 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → ▸ Le mounjaro peut il se conserver au frigo 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… ▸ Can we talk about the founder — what most people get wrong about this ▸ Getting the run around or I just do not have PCOS ? ▸ Anyone have experience switching from compound injection to pill: what to track and how to measure progress 📖 Lectin-Free Living — Eliminating inflammatory plant proteins that damage the gut lining and trigger the autoimmune responses that often stall… ▸ Can anyone help me lose my overweight ?? 30F, 75kgs, 5’7”? ▸ How I found out I had uterine cancer, what I wish I had known, and what everyone with PCOS should know about their period if you're on a GLP-1 like semaglutide or tirzepatide ▸ Started at 270 pounds at the beginning of last year, at the end I was 179 pounds! How do I look for those with hypothyroidism or Hashimoto's ▸ Integrating Japanese food philosophy to OMAD? ▸ How to safely fast as a teen? 📖 Visceral Fat — The dangerous 'hidden' fat stored around internal organs that drives chronic disease and is specifically targeted by our… 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → ▸ What I learnt as a physician about having Hashimoto for myself and what helped on a low-carb or ketogenic diet ▸ Feeling judged for wanting kids younger with PCOS? ▸ New menopause symptom, deep intense chills anyone — evidence-based answer for CFP patients ▸ Why has no doctor explained this to me for long-term maintenance (not just short-term) ▸ Mounjaro diet plan, supplements and workout for those with hypothyroidism or Hashimoto's ▸ Upped dosage + changing patch day — evidence-based answer for CFP patients ▸ E Patch to Injections how long did you leave your patch on: what to track and how to measure progress 📖 GLP-1 Receptor Agonist — A class of medication that mimics natural hormones to improve insulin secretion and slow gastric emptying, used strategi… ▸ What a 55 water fast did for me for those with hypothyroidism or Hashimoto's ▸ What's a good Soy Sauce alternative for Asian Cuisine — what does the research actually say? 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → ▸ Fuck is Almond milk — what does the research actually say? 📖 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… ▸ How does smoking affect GERD while taking tirzepatide? ▸ Same Workout Until it becomes Zone 2: how to talk to your doctor about this ▸ Had my annual physical today: what to track and how to measure progress 📖 Anti-Inflammatory Protocol — A way of eating that prioritizes whole foods and eliminates triggers to quiet the internal 'fire' that prevents fat cell… ▸ How I found out I had uterine cancer, what I wish I had known, and what everyone with PCOS should know about their period for people with insulin resistance ▸ How should I go about asking my doc? ▸ Ive been taking 15mg of tirzepatide for a year and my weight has stalled out with no diet change. What can I do?