Have you been thinking about making some lifestyle changes? Perhaps it’s time to face the music after all that comfort eating during the corona quarantine. Or maybe the thought of donning a swimsuit is a little more daunting this year.

While it’s always a good thing to try and improve our eating, most of us face the same recurring problem: our willpower only lasts so long.

Yes, we always seem to start off strong. Things are going well and the scale is starting to go down and we think this time is finally going to be different. Then suddenly, we crash and burn. Maybe we receive some stressful news. Or we get stuck in traffic. Or PMS hits us like a freight train. Or we have another work project dropped into our already full inbox.

In that moment, our willpower evaporates and we grab the Ben & Jerry’s without even stopping to think about it. As the guilt and shame slowly set in, we scramble to rationalize our lapse in willpower. It can be tempting to conclude, “I just keep failing. I’ll never be strong enough to do this.”

So how do we escape this cycle of failure and find lasting success? Do we throw more willpower at it? Listen to a few more motivational TED talks? Find another new diet guru to follow? Buy the latest bestseller or join a different gym or get ourselves a workout buddy?

While those things certainly won’t hurt, most of us know deep down that they’re not the answer. We’ve tried all those tricks and more, only to end up with the same fruitless results.

I’d like to suggest that the key to lasting change is in finding a bigger “why.” When we isolate this kind of powerful internal motivator and move it to the center of our minds and hearts, we access a source of energy that’s previously remained untapped. It’s the thing that will spur us on through the bad days and challenging moments when we want to give up. And the results will be astonishing.

I learned this for myself more than 15 years ago in my attempts to clean up my very out-of-control diet. For a long time, I’d been a huge sugar junkie and emotional eater. Chocolate was my bliss, my happy place, and my therapy in a little brown wrapper. I reached for sugar when I was happy, sad, bored, stressed, or anything in between. Truth is, I couldn’t imagine life without it.

Occasionally, though, I’d see the wrong number on the scale or my favorite jeans wouldn’t zip up all the way. So, lit up with fresh determination, I’d muster up all my willpower and dive into another new diet. At times I lasted several weeks or months, but most of the time my willpower was gone after only a few days. No matter how hard I tried, the chocolate always seemed to win out in the end.

Now I understand that my “why” just wasn’t big enough. Seeing a smaller number on the scale was an appealing thought, but it wasn’t motivating enough to hold me strong when things got tough. My continual failure was evidence that, deep down, my desire to binge on sugar was more powerful than my desire to fit in smaller jeans. While I always thought I was motivated enough to eat better, my true feelings kept revealing themselves in my choices.

However, one day, I found a much bigger why, almost by accident. Through the book recommendation of a friend, I was shocked to learn that a high sugar diet is linked to depression, anxiety, mood swings, restlessness, a short temper, and a host of other emotional problems. I struggled with all of those things, but I’d always assumed it was because of my hormones or my crazy kids or my stressful life. I had no idea I was causing my own emotional misery simply by what I was choosing to put in my mouth.

Suddenly, my motivation to eat better completely changed. Chocolate no longer seemed like my best friend, but an awful enemy who’d sent me spiraling into the depths of depression. With just that one shift in my mindset—just that one new and very powerful “why”—I found the motivation that would keep me on the path for the next 15 years and give me the strength to make some permanent changes in my health. (I’m also happy to report that the depression has been gone ever since I gave up the sugar).

So before you jump into a new diet or dive into an over-the-top workout plan, take the time to stop and ask yourself: what’s my motivation behind all this? What’s driving me to change? Is it just to see a different number on the scale? While that isn’t necessarily a bad reason to start with, often that motivation won’t be strong enough to carry you through the difficult days when your willpower is gone and you’re tempted to slide back into old patterns.

Dig a little deeper and find a why that’s bigger than just the generic “I want to lose weight” or “I’d like to feel better.” Ask yourself what it is you really, truly want. Is it to be able to play with your grandkids? To run up the stairs without huffing and puffing? To get off your expensive and side-effect-causing medications? Or like me, are you ready to calm the emotional upheaval that’s tied to a diet of doughnuts, Twinkies, and Diet Coke?

If you’ll do the work to find a why that truly motivates you, I believe with all my heart you’ll find the ability to change your life forever.