How long should I try keto before deciding if it works?

The honest answer: 60-90 days of proper keto before drawing conclusions. Here's why each phase matters:

Weeks 1-3: Adaptation phase. Your body is switching metabolic machinery. Results are unpredictable and volatile — some people lose a lot, some plateau. Not representative of what keto will do for you long-term.

Weeks 4-8: You're fat adapted. Appetite starts regulating. Energy stabilizes. This is when keto becomes your new normal rather than a forced restriction. Weight loss becomes more consistent.

Months 3+: Long-term adaptation. Your athletic performance returns (if it dropped), metabolic rate has adjusted, and you have reliable data about what pace of loss is sustainable for you specifically.

Week 2 being minimal is completely normal. It's possibly the worst week to evaluate because the initial water weight drop is over and fat adaptation isn't complete yet. Don't quit on week 2 of anything.

My week 2 was my worst week — I nearly quit too. I had lost 9 lbs week 1, then gained 2 lbs back week 2 and was furious. By month 2 I'd lost 18 more lbs. The week 2 stall/slight regain is so common it should be in the official keto guide.

Think of it like this: if keto were a job, week 2 is training week where you're getting paid less while you learn. Month 3 is when you're fully productive. Don't quit during training week.