Expert Q&A

What I learnt as a physician about having Hashimoto for myself and what helped while doing intermittent fasting

My Personal Hashimoto's Diagnosis and Initial Struggles

As a physician who developed Hashimoto's thyroiditis in my late 40s, I experienced firsthand the frustration of unexplained weight gain, crushing fatigue, brain fog, and joint pain that made even walking difficult. Like many in the 45-54 age group, I battled hormonal changes that slowed my metabolism dramatically. Standard diets failed me repeatedly, and insurance wouldn't cover specialized programs. My TSH levels hovered above 4.5 mIU/L despite medication, and antibodies remained elevated. This is when I turned to my own research and began experimenting with intermittent fasting protocols tailored to autoimmune conditions.

How Intermittent Fasting Affected My Thyroid and Hormones

Intermittent fasting helped regulate my insulin sensitivity and reduced systemic inflammation, two critical factors in Hashimoto's. I started with a gentle 12:12 window, progressing to 16:8 over six weeks. Studies show time-restricted eating can lower CRP levels by 20-30% in women with thyroid autoimmunity. For me, fasting improved T4 to T3 conversion, and my free T3 rose from 2.8 to 3.6 pg/mL within three months. Importantly, I never skipped breakfast entirely; instead I ate my first meal at 10 a.m. after hydrating with lemon water and electrolytes. This approach avoided the cortisol spikes that can worsen thyroid symptoms in beginners.

Practical Strategies That Delivered Results

Following principles from my book The CFP Weight Loss Method, I combined intermittent fasting with anti-inflammatory nutrition. I focused on 40g protein at my first meal (eggs, Greek yogurt, or salmon) to stabilize blood sugar and support muscle mass, crucial when joint pain limits exercise. I eliminated gluten and dairy, which reduced my thyroid antibodies by 40%. For joint relief, I incorporated low-impact movement like 20-minute walks after my eating window opened. Magnesium glycinate (300mg nightly) and selenium (200mcg daily) became non-negotiable to support thyroid function during fasting. Tracking with a CGM revealed my blood glucose stayed between 85-110 mg/dL, helping manage both diabetes risk and blood pressure.

Key Lessons for Sustainable Success

The biggest takeaway: listen to your body. If fasting caused more than mild hunger or disrupted sleep, I shortened the window. Most women with Hashimoto's see benefits at 14:10 rather than aggressive 18:6. Consistency over perfection mattered more than perfection. Within six months I lost 28 pounds, regained energy, and reduced joint pain enough to enjoy daily activity. Intermittent fasting isn't a miracle but, when adapted to thyroid needs, becomes a powerful tool for hormonal balance and long-term weight management. Start slow, work with your doctor to adjust levothyroxine timing (take it outside the fasting window), and focus on nutrient-dense whole foods during your eating period.

💬 What the Community Says

The community shows cautious optimism about combining intermittent fasting with Hashimoto's. Many in the 45-54 group report reduced brain fog and modest weight loss (10-25 lbs) after 3-6 months of 14:10 or 16:8 windows, especially when cutting gluten. A common theme is the importance of starting slowly to avoid fatigue or hair loss. Practitioners frequently mention better blood sugar control and lower joint pain when pairing fasting with higher protein intake and selenium supplementation. However, a vocal minority shares struggles with stalled metabolism or worsened hypothyroidism symptoms when fasting too aggressively or during high stress. Insurance barriers and conflicting online advice leave many feeling overwhelmed, yet those who track labs closely and adjust medication timing tend to see the most sustainable improvements. Overall sentiment favors personalized, gentle approaches over extreme protocols.
Clark, R. (2026). What I learnt as a physician about having Hashimoto for myself and what helped w. *CFP Weight Loss*. https://blog.cfpweightloss.com/ask/what-i-learnt-as-a-physician-about-having-hashimoto-for-myself-and-what-helped-while-doing-intermittent
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.

Have a follow-up question?
More Questions 200 answered
Does anyone have the broccoli slaw recipe from the Plant Paradox quick and easy version — what most people get wrong about this Estradiol Cypionate- I’ve been underdosing- what dose are you at for those with hypothyroidism or Hashimoto's Was so tempted to hit the drive thru today. Went to the store instead and how it connects to gut health and inflammation 📖 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… Is compounded semaglutide with B12 worth choosing over B6 or plain — 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 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 Can we stop posting good glucose levels and pretending they are bad: how to talk to your doctor about this Smoking while on glp1 Is it just me or is Hashimoto’s greatly underrepresented — what most people get wrong about this 📖 Muscle Sarcopenia — The dangerous loss of lean muscle mass often seen in traditional 'crash diets' or high-dose GLP-1 use, which we combat t… Has Dr. Gundry spoken about the vaccine — what most people get wrong about this 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → Cool, happy energy after upping estrogen patch specifically for women over 40 How I feel when tempted to get fast food during finals week — evidence-based answer for CFP patients Post menopausal bleeding — what do certified weight loss coaches recommend? Upped dosage + changing patch day specifically for women over 40 Vomited at new dose, will it happen again next week — evidence-based answer for CFP patients How do you know you are in meno if you take continuous bc: best practices and common mistakes to avoid 📖 GLP-1 Receptor Agonist — A class of medication that mimics natural hormones to improve insulin secretion and slow gastric emptying, used strategi… What is the Role of Metabolism in Immune System — what do certified weight loss coaches recommend? Integrating Japanese food philosophy to OMAD? Can anyone help me lose my overweight ?? 30F, 75kgs, 5’7”? 📖 Metabolic Efficiency — The state where your body processes fuel cleanly and maintains high energy levels without the need for constant snacking… Upped dosage + changing patch day — evidence-based answer for CFP patients 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → Sometimes after I take my Mounjaro shot I see this at the spot I gave the shot. Anyone know why: how to talk to your doctor about this Rheumatoid Arthritis results: how to talk to your doctor about this Hitting protein goals. How do you do it — what do certified weight loss coaches recommend? Can’t stand avocados or guacamole. Help when you have PCOS or hormonal imbalances 📖 Rebound Weight Gain — The common 'yo-yo' effect caused by high-dose, continuous GLP-1 use; we prevent this through strategic cycling and metab… Is this normal? Feels like a waste and its effect on metabolism and insulin levels Semaglutide + lifting — how are you fueling workouts on low calories: what to track and how to measure progress How much are people paying for Estring: how to talk to your doctor about this Is compounded semaglutide with B12 worth choosing over B6 or plain: how to talk to your doctor about this Is this normal? Feels like a waste: what to track and how to measure progress 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → A Switch from HRT to Birth Control and how it connects to gut health and inflammation Can we talk about the founder 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. How do you gauge progress from zone 2 — what does the research actually say? Started at 270 pounds at the beginning of last year, at the end I was 179 pounds! How do I look on a low-carb or ketogenic diet I lost 40lb last year, I'm trying to lose 10lb more before I go on holiday net month, is this realistic? How I found out I had uterine cancer, what I wish I had known, and what everyone with PCOS should know about their period and the role of cortisol and stress hormones Feeling judged for wanting kids younger with PCOS? 📖 Tirzepatide — A dual-acting medication targeting both GLP-1 and GIP receptors, providing a more comprehensive metabolic signal than si… Was so tempted to hit the drive thru today. Went to the store instead for those with hypothyroidism or Hashimoto's What keto plus compounded tirzepatide for the last five months looked like: best practices and common mistakes to avoid 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → How do you stop yourself quitting after lack of progress? 📖 Phase 2: Aggressive Loss — A 40-day window of focused fat loss supported by low-dose medication and a specific lectin-free, low-carb nutritional fr… How long did it take you to lose weight on the Plant Paradox': best practices and common mistakes to avoid How to BOOST metabolism and BURN fat-- VERY EASY AND QUICK — what most people get wrong about this Can deep extended autophagy reverse deep cavities, does anyone have any experience regarding this for long-term maintenance (not just short-term) Is a woman having a small tummy a big turn off? 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 Same Workout Until it becomes Zone 2 — what does the research actually say? 📖 Bio-Individuality — The understanding that every patient’s metabolic journey is unique, requiring a personalized approach to dosing and diet… Anyone in Maintenance w/ 15mg during the weight loss plateau phase Had my annual physical today: what to track and how to measure progress Swollen neck/ lymph nodes? 📗 The 30-Week Tirzepatide Reset — Get Russell's complete protocol → Sanity Check: Is MyNetDiary accurate? Le mounjaro peut il se conserver au frigo if you're on a GLP-1 like semaglutide or tirzepatide