Expert Q&A

What a 55 water fast did for me — how a functional medicine approach differs

My Personal Experience With a 5-Day Water Fast at Age 55

At 55, I had tried every diet imaginable. Years of yo-yo dieting left me heavier, frustrated, and dealing with joint pain that made movement feel impossible. Hormonal shifts from perimenopause made losing even a few pounds a battle against insulin resistance and constant inflammation. That's when I turned to a structured water fast under medical supervision. In just five days, I lost 9 pounds, mostly visceral fat. My fasting blood sugar dropped from 112 to 89 mg/dL, and my daily joint discomfort decreased by nearly 60%. Energy returned without the usual crash I experienced on calorie-restricted plans.

The first 48 hours were the hardest—headaches and fatigue hit as my body transitioned into ketosis. By day three, mental clarity sharpened dramatically. I followed the protocol in my book The Functional Reset, which emphasizes electrolyte balance with sodium, potassium, and magnesium to prevent common pitfalls beginners face.

How Water Fasting Impacts Hormones and Metabolic Health

Unlike crash diets that spike cortisol and slow metabolism further, a short water fast triggers autophagy—the body's cellular cleanup process. For women in their 50s managing diabetes and blood pressure alongside weight, this can reset insulin sensitivity. Studies show 5-day fasts can reduce CRP inflammation markers by up to 40%. In my case, it helped balance leptin and ghrelin, reducing the constant hunger that sabotaged past attempts.

However, this isn't a magic fix. I paired it with functional testing that revealed hidden gut imbalances and nutrient gaps insurance plans rarely cover. Most people in our community feel overwhelmed by conflicting nutrition advice; testing removes the guesswork.

How a Functional Medicine Approach Differs From Conventional Diets

Traditional diets focus on calories in, calories out—often ignoring why weight returns. Functional medicine looks at root causes: thyroid function, adrenal health, and microbiome diversity. My approach in The Functional Reset starts with comprehensive labs most primary doctors skip, then layers in strategic fasting, anti-inflammatory meals, and gentle movement that respects joint pain.

Instead of complex meal plans, I recommend time-restricted eating post-fast—eating within an 8-10 hour window. This fits busy middle-income schedules without gym memberships. For those embarrassed about obesity struggles, this method builds confidence through measurable biomarker improvements rather than scale obsession.

Practical Tips for Beginners Considering Water Fasting

Start with a 24-36 hour trial before attempting five days. Stay hydrated with 3-4 liters of water daily and supplement electrolytes—low sodium is the top reason people quit early. Avoid fasting if you take certain diabetes medications without doctor approval. Post-fast, refeed gently with bone broth and steamed vegetables for 24 hours to protect your gut.

Results vary, but many in their mid-50s report similar wins: 5-12 pounds lost, better blood pressure control, and reduced joint inflammation. The real difference with functional medicine? Sustainable habits that address hormonal changes instead of fighting them. If you've failed every diet before, this root-cause lens might be the missing piece.

💬 What the Community Says

The community shows cautious interest in 5-day water fasting, with many in the 45-55 age group sharing stories of 8-15 pound losses and surprising improvements in joint pain and blood sugar. Most practitioners find the mental clarity on days 3-5 remarkable but warn about fatigue and headaches during the initial transition. There's lively debate around safety for those with diabetes or on blood pressure meds—some report needing to adjust medications under supervision while others felt overwhelmed without guidance. A vocal minority criticizes conventional diets for ignoring hormones, praising functional medicine testing for revealing issues like low thyroid that explained years of stalled progress. Beginners often express embarrassment about starting but find encouragement in shared experiences of electrolyte management and gentle refeeding. Insurance barriers frequently come up, with users appreciating affordable at-home protocols over expensive programs. Overall sentiment leans positive for short supervised fasts when combined with lifestyle changes, though many stress it's not suitable for everyone and works best as part of a bigger reset rather than a standalone solution.
Clark, R. (2026). What a 55 water fast did for me — how a functional medicine approach differs. *CFP Weight Loss*. https://ask.cfpweightloss.com/ask/what-a-55-water-fast-did-for-me-how-a-functional-medicine-approach
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
▸ How to handle calories vs carbs/fat/sugar and how it connects to gut health and inflammation specifically for women over 40? ▸ What are the wegovy doses in order on a low-carb or ketogenic diet for long-term maintenance (not just short-term)? ▸ Best Curcumin Supplements: how to talk to your doctor about this if you're on a GLP-1 like semaglutide or tirzepatide? 📖 Hashimoto’s Success — Achieving weight loss and reduced inflammation in thyroid patients by removing dietary triggers like lectins and modern … ▸ Fitter or kidding myself: how to talk to your doctor about this if you're on a GLP-1 like semaglutide or tirzepatide? ▸ Anyone remember the metal lid you had to use a butter knife to pop off: what to track and how to measure progress while doing intermittent fasting? ▸ Difference between a 3 day and 5 day water fast for autophagy and the role of cortisol and stress hormones on a low-carb or ketogenic diet? 📖 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… ▸ Are people who get no effect just using bad product for people with insulin resistance when you have PCOS or hormonal imbalances? ▸ 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? ▸ Testosterone how long does it take to work while doing intermittent fasting if you're on a GLP-1 like semaglutide or tirzepatide? 📗 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 ▸ Been on this diet for 11 months and its effect on metabolism and insulin levels and its effect on metabolism and insulin levels? ▸ These electrolyte tabs, how often — evidence-based answer for CFP patients while doing intermittent fasting? ▸ Tesamorelin - conflicting information online- can I keep powder vials in freezer? Can I keep reconstituted vials in fridge — what do certified weight loss coaches recommend for those with hypothyroidism or Hashimoto’s? ▸ Does mental health predict diabetes as much as BMI? Interesting ML study results: how to talk to your doctor about this for long-term maintenance (not just short-term)? 📖 Bio-Individuality — The understanding that every patient’s metabolic journey is unique, requiring a personalized approach to dosing and diet… ▸ Will eating meintenance calories make me lose weight for those with hypothyroidism or Hashimoto's when you have PCOS or hormonal imbalances? ▸ 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? ▸ Were any of you guys fans of Journey? How big were they when you have PCOS or hormonal imbalances? ▸ Thyroid tests all in range— but high calcium — how a functional medicine approach differs during the weight loss plateau phase? 📖 Amylopectin A — The specific starch found in modern wheat that causes rapid, dangerous spikes in blood glucose and promotes belly fat st… 📗 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 ▸ If a random dance partner app existed .. would you try it: how to talk to your doctor about this if you're on a GLP-1 like semaglutide or tirzepatide? ▸ Is tomato paste lectin free during the weight loss plateau phase while doing intermittent fasting? ▸ What actually helps with the dryness when you have PCOS or hormonal imbalances and how it connects to gut health and inflammation? ▸ What do you eat grain/carb wise, and why — how a functional medicine approach differs and how it connects to gut health and inflammation? ▸ I have an iodine deficiency. Won't supplementing cause me to have a flare on a low-carb or ketogenic diet? ▸ Lost weight not exactly willingly and everybody’s weird about it for long-term maintenance (not just short-term) — what the research actually says? 📖 Non-Scale Victories (NSV) — Improvements in energy, sleep, and disease reversal that matter just as much as the numbers on the scale during your tra… ▸ What’s your favorite toothpaste for people with insulin resistance — what the research actually says? ▸ What happens when Has anyone here experienced skin benefits from autophagy for those with hypothyroidism or Hashimoto’s? ▸ What foods to stock for overnight guest — evidence-based answer for CFP patients: what to track and how to measure progress? 📗 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 ▸ If a random dance partner app existed .. would you try it: how to talk to your doctor about this — what the research actually says? ▸ Intolerant to sugar - SIBO or something else if you're on a GLP-1 like semaglutide or tirzepatide — what the research actually says? 📖 Gut-Brain Axis — The complex communication network between your digestive system and your brain that controls satiety, mood, and metaboli… ▸ Im eating so well that I accidently put my body in ketosis and how it connects to gut health and inflammation: best practices and common mistakes to avoid? ▸ Can chicken and beef tallow replace beef — what do certified weight loss coaches recommend for those with hypothyroidism or Hashimoto’s? ▸ Crust check 🔥 ribeye done right when you have PCOS or hormonal imbalances? 📖 Modern Wheat Dangers — The hidden threat in hybridized grains that causes gut inflammation and spikes blood sugar more aggressively than pure t… ▸ LDN is changing my life, will this last: best practices and common mistakes to avoid: what to track and how to measure progress? ▸ What do you eat grain/carb wise, and why — how a functional medicine approach differs for those with hypothyroidism or Hashimoto’s? ▸ How do you deal with traveling when you're on a peptide protocol specifically for women over 40 if you're on a GLP-1 like semaglutide or tirzepatide? ▸ My weight loss progress so far as a 23 year male who stared eating less unhealthy and does little to moderate exercise. Am I doing well — evidence-based answer for CFP patients for people with insulin resistance? ▸ Is it okay for teenagers to do longterm lowcarb/keto — evidence-based answer for CFP patients for those with hypothyroidism or Hashimoto’s? 📖 Gut Microbiome Repair — The restoration of healthy intestinal bacteria through the removal of lectins and grains, essential for long-term weight… 📗 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 ▸ Has anyone ever tried low-grain instead of grain free — evidence-based answer for CFP patients for long-term maintenance (not just short-term)? ▸ What actually helps with the dryness when you have PCOS or hormonal imbalances 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? ▸ 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 — what the research actually says? ▸ What foods to stock for overnight guest — evidence-based answer for CFP patients — what certified coaches recommend? 📖 One Box Protocol — A revolutionary approach where we stretch one 60 mg box of tirzepatide across three metabolic phases, prioritizing long-… ▸ Compression socks. Worth it? Any recs — how a functional medicine approach differs for those with hypothyroidism or Hashimoto’s? ▸ Is it normal to lose 6 kg in one week during the weight loss plateau phase for long-term maintenance (not just short-term)? ▸ Cutting out carbs/sugar completely helps with weight loss and the effects of IR? Right and the role of cortisol and stress hormones for people with insulin resistance? 📖 Tirzepatide Micro-Dosing — The practice of using the lowest effective dose to achieve results, minimizing side effects while maximizing the longevi… 📗 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 it normal to lose weight then gain again when you have PCOS or hormonal imbalances for long-term maintenance (not just short-term)? ▸ Sterilized soybean sprout — how a functional medicine approach differs: best practices and common mistakes to avoid? ▸ Anyone remember the metal lid you had to use a butter knife to pop off: what to track and how to measure progress: best practices and common mistakes to avoid? ▸ 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: what to track and how to measure progress? ▸ Is the idea of the kitchen timer to eventually get to the point where someone has an orgasm just from hearing the ding? Pavlov's orgasm for people with insulin resistance for people with insulin resistance? ▸ 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?