How Long Does It Take to Form a Healthy Eating or Exercise Habit?

We’ve all been there. We start a new routine with the best of intentions but fall back into old patterns a few weeks later. Whether it’s making better food choices, exercising regularly or cutting back on sugar building new habits can feel hard. But how long does it actually take for something to become a habit?

The truth is there’s no one-size-fits-all answer. However, understanding how habits are formed and what helps them stick can make the process feel a lot more manageable.

Understanding How Habits Work

A habit is a behaviour that becomes automatic. To begin with it takes effort to remember and stick with it. But, over time, your brain starts to associate certain cues (like a time of day or a place) with that behaviour until it becomes part of your normal routine.

This is why you brush your teeth without thinking or automatically make a coffee in the morning. Those are habits that were formed through repetition.

The same can happen with positive health behaviours like going for a walk after dinner or choosing a balanced lunch. But just like brushing your teeth these habits take time to become natural.

How Long Does It Really Take?

There’s a common myth that it takes 21 days to form a habit. Research shows it’s usually longer. A 2009 study found that it takes, on average, around 66 days for a new habit to become automatic. For some people it can take as little as 18 days. For others it might take more than 100.

Ultimately it depends on the person, the habit, and how difficult the change is. Starting a daily walk may become a habit faster than switching from takeaway to home-cooked meals every night.

The key message? Be patient with yourself. Missing a day or two doesn’t mean you’ve failed, it just means you’re human!

Making Eating Habits Stick

If you want to eat better start small. Choose one simple change and stick with it until it feels natural. That might be eating a piece of fruit every afternoon, drinking more water or planning your dinners in advance.

The more you repeat it in the same context (like always eating your fruit with lunch) the easier it becomes. Eventually, your brain starts to expect it and it becomes second nature.

Avoid trying to change everything at once. Overhauling your entire diet in a week is more likely to lead to burnout than success.

Creating an Exercise Routine You Can Stick To

Exercise habits can be tricky to form especially if you’re busy, tired or haven’t exercised in a while. The key is to start with something manageable and make it as easy as possible to follow through.

That might mean doing 10 minutes of stretching in the morning or a walk around the block after dinner. When you keep it small and achievable you’re more likely to show up. Showing up regularly is what builds the habit.

Try to connect your movement to something you already do every day, like walking after lunch or doing a quick routine while the kettle boils. These natural triggers help cement the behaviour into your brain.

What Helps Habits Last?

Repetition is important! But remember it’s not the only factor. The habits that stick are the ones that feel rewarding in some way. That doesn’t mean you need to love every workout or crave vegetables but noticing the benefits (like better energy, improved mood or clearer skin) can help motivate you to keep going.

It also helps to track your progress. A habit tracker, calendar tick-off, or even a note in your phone can remind you how far you’ve come. And if you miss a day? Just start again tomorrow. It’s the long-term pattern that matters most.

Progress, Not Perfection

There’s no magic number of days that guarantees a habit will stick forever. But if you show up regularly (without needing to be perfect) those daily choices will add up.

Remember: habits aren’t formed in a straight line. Some days will feel easier than others. The goal isn’t to never miss a day. The goal is to build something that becomes part of your life in a way that supports your health, not adds stress.

So whether you're trying to move more, eat better or drink more water, focus on consistency over time. Small steps, done often, are what create lasting change.