Every guide
45 pages, grouped by section. Start with the basics if you are new, or jump to the situation that matches yours.
Start here
What carb fasting is and why it works.
The plan
Fast days, normal days, and how to lay out your week.
Guides
Practical how-tos for fast days, normal days, and the habits around them.
- A simple carb fasting weekly meal plan A sample week with near-zero-carb fast days on Monday, Wednesday, and Friday, plus normal-carb days and example meals to adapt. 2 min
- Apple cider vinegar before meals Whether diluted apple cider vinegar before a carb meal blunts the post-meal glucose rise and how it fits a carb fasting day. 1 min
- Berberine dosage and timing Berberine doses and timing used in trials, plus medication and pregnancy cautions to clear with your clinician first. 2 min
- Berberine vs. Ozempic How berberine and Ozempic compare for weight, including evidence, effect size, mechanisms, and medication cautions. 2 min
- Carb fasting at restaurants How to handle a fast day at a restaurant by building the plate from protein and vegetables, skipping starch, and ordering by cuisine. 2 min
- Carb fasting on holidays How to enjoy Thanksgiving and other holidays by making the feast a normal carb day and scheduling fast days around it. 1 min
- Eat your carbs last Eating vegetables and protein before carbs can lower the post-meal glucose and insulin rise on normal-carb days. 1 min
- Fast-day meal ideas Simple, satisfying near-zero-carb meals for fast days, including breakfast, lunch, dinner, and snacks you'll look forward to. 1 min
- How to become fat-adapted What "fat-adapted" means and how repeated carb fast days rebuild metabolic flexibility over days to weeks on your own timeline. 2 min
- Natural Ozempic alternatives, ranked by the evidence How supplements and carb-fasting habits compare with Ozempic for post-meal glucose and weight, ranked by the evidence. 2 min
- Quit keto? Try this instead Quit keto? Carb fasting pairs near-zero-carb fast days with normal-carb days, so you can keep carbs in your life. 1 min
- The whole-food swap list for normal days Simple 80/20 carb swaps for normal days that keep the carbs you love while making whole-food versions the default. 2 min
- Using a CGM without diabetes A guide to over-the-counter continuous glucose monitors for carb fasting, including what they show and what time in range means. 2 min
- Walking after meals and blood sugar Why a short, easy walk after eating blunts the post-meal glucose rise and how the habit pairs with carb fasting. 2 min
- What to eat on a carb fasting fast day A practical food list for fast days, including protein, healthy fats, non-starchy vegetables, foods to limit, and foods to skip. 1 min
Compare
Carb fasting next to keto, intermittent fasting, GLP-1 drugs, and the rest.
- Carb fasting vs. a low-carb diet A low-carb diet keeps carbs down every day. Carb fasting concentrates restriction into fast days and leaves normal days alone. 1 min
- Carb fasting vs. carb cycling Carb fasting and carb cycling both alternate carbohydrate intake. Carb fasting uses two day types with no macro math. 1 min
- Carb fasting vs. GLP-1 drugs (Ozempic & Wegovy) How GLP-1 drugs like Ozempic and Wegovy compare with carb fasting, including weight regain after treatment and "natural Ozempic" claims. 1 min
- Carb fasting vs. intermittent fasting Intermittent fasting changes when you eat. Carb fasting changes what you eat on certain days. Here's how their evidence and tradeoffs compare. 1 min
- Carb fasting vs. keto Keto keeps carbs very low every day. Carb fasting uses scheduled near-zero-carb days, giving you low-carb periods without permanent restriction. 1 min
Who it's for
Where to start if you have prediabetes, type 2 diabetes, weight to lose, or specific concerns.
- Carb fasting and type 2 diabetes How carb fasting relates to type 2 diabetes, the glycemic evidence, and why only your prescriber should change your medication. 2 min
- Carb fasting for metabolic syndrome What metabolic syndrome is, how low-carb eating affects its five markers, and where carb fasting fits alongside clinical care. 2 min
- Carb fasting for prediabetes What prediabetes is, how lower-carb eating may improve glycemia, and why carb fasting can be one way to act early. 1 min
- Carb fasting for weight loss How carb fasting may support fat loss through scheduled fat-burning windows, steadier cravings, and a plan that keeps carbs on the menu. 1 min
- Carb fasting for women Why a flexible carb-fasting pattern may suit women burned by rigid diets, how to adapt it, and why pregnancy needs separate guidance. 1 min
Science
Metabolic flexibility and the studies behind it.
Biomarkers
The numbers worth tracking and what they mean.
- Blood glucose and carb fasting Fasting vs. post-meal blood glucose, the standard thresholds, the spike-crash-craving loop, and how carb fasting may steady your numbers. 2 min
- Carb fasting and your lipid panel How carb fasting may affect triglycerides, HDL, and LDL cholesterol, and why you should get a baseline test and recheck. 1 min
- CGM and carb fasting What a continuous glucose monitor is, why "time in range" matters, and how a CGM lets you watch a carb-fasting fast day flatten your glucose curve. 2 min
- Fasting insulin & HOMA-IR Learn what fasting insulin and HOMA-IR show about insulin resistance and how lower carbohydrate exposure may change these numbers. 2 min
- HbA1c and carb fasting HbA1c is your ~3-month average blood sugar. Here's what the numbers mean and how lower-carb eating like carb fasting tends to move them. 1 min
- Ketones and carb fasting What blood and urine ketones mean for carb fasting, why nutritional ketosis is normal, and how it differs from diabetic ketoacidosis. 2 min
- The biomarkers that track carb fasting Learn which blood and sensor measures can show whether carb fasting is working, including glucose, HbA1c, insulin, ketones, and lipids. 1 min
Safety
Who should be careful, medications, and the adjustment period.
- Carb fasting and LDL cholesterol How carb fasting affects LDL cholesterol, triglycerides, and HDL, including who may see LDL rise and when to check with your clinician. 2 min
- Carb fasting and pregnancy Pregnancy raises carbohydrate needs and changes how ketones matter. Learn why very-low-carb eating needs obstetric guidance. 1 min
- Carb fasting and your medications Carb fasting can lower blood sugar fast. If you take insulin, sulfonylureas, or SGLT2 inhibitors, your medication plan may need to change. 2 min
- Is carb fasting safe? For most healthy adults, alternating carb days is low-risk. Some medications, pregnancy, and certain conditions require medical oversight. 1 min
- The "low-carb flu" and adaptation on carb fasting Why the first fast days can feel off, how hydration and electrolytes may help, and when to ease off and call your clinician. 1 min
- Who should not carb fast (without medical guidance) Who should skip carb fasting or get medical supervision first, including people who are pregnant, take insulin, or have disordered eating. 2 min
About this site
How we research, who writes here, and what we will not claim.
- Carb fasting results Carb fasting results start with the founder's tracked year. Member testimonials will appear when there are real results to share. 1 min
- Editorial policy How carbfasting.com is written, sourced, reviewed, and corrected, including our relationship with Freedomology. 2 min
- How we research The source hierarchy, citation standard, and honest evidence-grading behind every page on carbfasting.com. 1 min
- The data, starting with one person Carb fasting results begin with the founder's tracked self-experiment. A member data log is in progress. 1 min
The free book
The plan, the science, and 100 recipes. Free.
The Fat Switch by Greg Clement: The two-day plan, the science behind it, and 100 recipes. Enter your email and we send it over.
