Fasting & Keto, the Sustainable Way
Make intermittent fasting and lower-carb eating actually sustainable: ease into a window, keep your electrolytes and protein up, and stop the fatigue and cramps that make most people quit.
Ease into a gentle eating window Start ~12h overnight, build toward 14 to 16h if it suits you
A modest overnight fast is enough for most people. Build gradually and fast on busy days so you think about it less. Longer or stricter is not better.
Replace your electrolytes Sodium, potassium and magnesium daily, especially while fasting or low-carb
Most fasting and keto fatigue, headaches and cramps are an electrolyte problem, not a calorie one. Replacing them is the single biggest fix for sustainability.
Add magnesium As directed, evening is fine
Magnesium is commonly low on lower-carb diets and supports sleep, cramps and energy. DeLauer flags it as a near-universal addition.
Break your fast with protein Lead with 30g+ protein at your first meal
Protein protects muscle during fasting and keeps you full. DeLauer's evolved view leans higher-protein to preserve muscle and metabolic rate.
C8 MCT oil for energy in the window ~1 tbsp, optional, build up slowly
A small RCT found MCT oil raised ketone (BOHB) levels more than a placebo oil, though it did not significantly speed up time to reach ketosis; it is a modest, optional addition, not essential.
Cover the keto micronutrient gaps Omega-3 and vitamin D3 with K2
Lower-carb eating can leave gaps; DeLauer's keto supplement list centres on omega-3, vitamin D and K2 alongside electrolytes and magnesium.
When you fast or cut carbs, your body sheds water and with it sodium, potassium and magnesium, which is what causes the headaches, cramps and fatigue people blame on fasting itself.
View sources
48-hour fasting: how to do a 2-day fast, with electrolytes (Thomas DeLauer)
Science-Backed Wellness: Thomas DeLauer on Ketosis, Fasting, and Sustainable Health (Habits & Hustle w/ Gabby Reece)
Thomas DeLauer on keeping calories high enough during fasting (Instagram)
Thomas DeLauer: how the keto diet has evolved (16 adjustments)
DeLauer's top tips for going keto (electrolytes, fasting)
Symptoms during initiation of a ketogenic diet: a scoping review of occurrence rates, mechanisms and relief strategies (Skartun et al., Frontiers in Nutrition, 2025)
The Effect of Medium Chain Triglycerides on Time to Nutritional Ketosis and Symptoms of Keto-Induction in Healthy Adults: A Randomised Controlled Clinical Trial (Harvey et al., J Nutr Metab, 2018)
Not medical advice. This page is for education only and is not a substitute for professional medical care. Consult a qualified clinician before changing your health routine.
Independent curation. YourProtocol is an independent platform. This protocol is based on the publicly available work of Thomas DeLauer and is not created, reviewed, endorsed by, or affiliated with Thomas DeLauer or Nutrition Educator.
Is this for you
- People trying intermittent fasting who keep quitting from fatigue
- Anyone going lower-carb or keto who wants to feel good doing it
- People who want to lose fat without losing muscle
- Those who want the support stack that makes fasting sustainable
Cautions
- Fasting is not for everyone. Skip it, or get medical guidance first, if you are pregnant or breastfeeding, under 18, have a history of disordered eating, are underweight, or take medication (especially for diabetes) that requires food. If fasting drives preoccupation with food or restriction, stop.
- This protocol is about gentle, sustainable fasting, not extended or aggressive fasting. More restriction is not better, and we do not give calorie targets here.
- Electrolytes and magnesium are the fix for most fasting fatigue and cramps; if you feel unwell, eat and rehydrate rather than pushing through.
- Supplements fill gaps; they do not replace real food, protein and sleep. DeLauer recommends products via affiliate links, so verify brands independently.
- Educational only, not medical advice; speak to a clinician before big dietary changes.
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