Expert Q&A

Going for my first 36 hours. Any tips while doing intermittent fasting

Preparing Mentally and Physically for Your First 36-Hour Fast

I've guided thousands through their initial extended fasts, especially those in their late 40s and early 50s battling hormonal changes and stubborn midlife weight. A 36-hour fast means you'll finish dinner tonight and not eat again until breakfast in two days. This window triggers significant autophagy and insulin sensitivity improvements that shorter intermittent fasting windows often miss.

Start by choosing a low-stress weekend for your first attempt. Eat a nutrient-dense meal rich in healthy fats and protein the night before—think salmon, avocado, and leafy greens. This stabilizes blood sugar and reduces next-day hunger spikes that derail many beginners who have failed every diet before.

Hydration, Electrolytes, and Managing Common Side Effects

Dehydration and electrolyte imbalance cause 80% of discomfort during extended fasts. Drink at least 3-4 liters of water daily, adding a pinch of Himalayan pink salt or an electrolyte packet without added sugars. Magnesium glycinate (300mg at night) prevents muscle cramps and improves sleep, crucial when joint pain already limits your movement.

Expect hunger waves around mealtimes— they typically peak for 20 minutes then subside. Black coffee, green tea, or bone broth (under 50 calories) can help without breaking the fast. Walk gently for 10-15 minutes after these waves; light movement improves insulin response without exacerbating joint issues. In my methodology outlined in The Midlife Metabolic Reset, I emphasize that consistency with electrolytes beats willpower every time.

Monitoring Your Body and Breaking the Fast Correctly

Track symptoms: mild fatigue and headaches are normal as your body shifts to fat-burning, usually by hour 18. However, severe dizziness, rapid heartbeat, or confusion means you should stop. Those managing diabetes or blood pressure should consult their physician first, as fasting powerfully affects medication needs.

When breaking your 36-hour fast, start small with bone broth or a green smoothie. Avoid carb-heavy meals that can cause digestive distress or blood sugar rebound. A simple meal of eggs, spinach, and avocado works perfectly. This gentle refeed preserves the metabolic benefits that make intermittent fasting so effective for hormonal weight loss.

Building Sustainable Habits Beyond Your First Fast

Use this experience to build confidence. Most clients find the second 36-hour fast dramatically easier once they understand their personal hunger patterns. Combine this with my simple 16:8 daily intermittent fasting schedule on non-fasting days—no complex meal plans required. Focus on whole foods, adequate protein (1.2g per kg bodyweight), and resistance movements you can do at home.

Remember, the goal isn't perfection but consistency. Your first 36-hour fast proves you can succeed where previous diets failed. The metabolic flexibility gained helps reverse the hormonal barriers making weight loss feel impossible after 45.

💬 What the Community Says

The community shows cautious optimism about first 36-hour fasts, with many middle-aged beginners sharing that preparation with electrolytes made the difference between success and quitting by hour 20. Most report intense hunger around dinner time on day one but note it passes, especially with black coffee or walks. There's lively debate about adding bone broth—some insist it breaks the fast while others say small amounts help them complete it without blood sugar crashes. People managing blood pressure and diabetes frequently mention checking with doctors first. Joint pain sufferers appreciate suggestions for gentle movement instead of intense exercise. A vocal minority struggles with headaches and fatigue but celebrates completing their first extended fast as a major win after years of diet failures. Overall, lived experiences highlight that the mental barrier is bigger than the physical one, and repeat attempts get noticeably easier.
Cite this answer
Clark, R. (2026). Going for my first 36 hours. Any tips while doing intermittent fasting. *CFP Weight Loss*. https://ask.cfpweightloss.com/ask/going-for-my-first-36-hours-any-tips-while-doing-intermittent
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.

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