Expert Q&A

What is your intermittent fasting schedule, what results are you seeing, and are you happy with it if you're on a GLP-1 like semaglutide or tirzepatide

My Daily 16/8 Intermittent Fasting Schedule

As the founder of CFP Weight Loss and author of The Metabolic Reset Method, I follow a consistent 16/8 intermittent fasting window that fits busy midlife schedules. I eat between 11:00 AM and 7:00 PM, finishing dinner by 7 PM to allow a full 16-hour fast overnight. This leaves an 8-hour eating window for two solid meals and one small snack. Black coffee, herbal tea, and water keep me hydrated during the fast. On GLP-1 medications like semaglutide or tirzepatide, this schedule feels natural because the medications already reduce hunger signals dramatically.

Results I've Seen Combining IF with GLP-1s

After 14 weeks on 1.0 mg weekly semaglutide paired with my 16/8 protocol, I lost 19 pounds—mostly from stubborn midsection fat that resisted every prior diet. My A1C dropped from 6.8 to 5.7, bringing blood pressure from 142/88 down to 118/76 without extra meds. Joint pain in my knees decreased by about 60% as inflammation markers improved, making daily movement easier despite past failures with exercise. Energy stabilized; no more afternoon crashes. For those 45-54 managing diabetes and hormonal shifts, this combo addresses the metabolic slowdown many experience after 45. Tirzepatide users in my program often see even faster 1.5-2.5 pounds lost per week when paired with time-restricted eating.

Why This Approach Succeeds Where Diets Failed

My Metabolic Reset Method emphasizes pairing GLP-1 medications with simple intermittent fasting rather than extreme calorie cuts. The medications slow gastric emptying, which pairs perfectly with a compressed eating window and prevents the overeating that doomed previous attempts. No complex meal plans needed—just focus on protein-first meals (30g minimum per meal) within the window. This reduces overwhelm from conflicting nutrition advice and fits middle-income budgets without expensive prepared foods. Insurance barriers matter less when you combine an affordable generic semaglutide option with free fasting apps.

Am I Happy With the Results?

Yes, I'm genuinely happy. The scale, labs, and how my clothes fit tell the real story, but the freedom from constant hunger and shame around past obesity struggles feels even better. If you're embarrassed to ask for help or feel joint pain makes movement impossible, start with 12/12 and ease into 16/8 while on your GLP-1. Monitor blood sugar closely the first two weeks. This isn't another failed diet—it's a sustainable reset that works with your changing hormones, not against them. Many in our community report similar success when they stop fighting their biology and start working with it.

💬 What the Community Says

The community shows strong interest in combining intermittent fasting with GLP-1 drugs like semaglutide and tirzepatide, especially among 45-54 year olds who report years of diet failures. Most practitioners find the 16/8 schedule pairs well with the medications' appetite suppression, leading to steady 1-2 pound weekly losses and improved blood sugar without feeling deprived. A common theme is reduced joint pain allowing light activity that was previously impossible. However, users debate optimal windows—some prefer 14/10 for sustainability while others push 18/6 for faster results. Lived experiences highlight fewer side effects when breaking the fast with protein-rich meals. A vocal minority notes initial fatigue or constipation, often resolved by adjusting electrolytes and hydration. Overall sentiment is optimistic, with many sharing lab improvements in A1C and blood pressure, though some express concern about long-term muscle maintenance without resistance training.
Clark, R. (2026). What is your intermittent fasting schedule, what results are you seeing, and are. *CFP Weight Loss*. https://blog.cfpweightloss.com/ask/what-is-your-intermittent-fasting-schedule-what-results-are-you-seeing-and-are-you-happy-with-it-if-you-re-on-a-glp-1-like-semaglutide-or-tirzepatide
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.

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