WHO: Dr. Ali Zentner, internal medicine and obesity doctor
AGE: 42
CITY: Vancouver

By The Numbers: 326 at my heaviest, and currently 150. Height: 5'4''

The Weight Gain: I struggled with my weight ever since I was a kid. When I was nine years old, my mother took me to see a dietitian. I weighed 120 pounds, and the dietitian told me that if I stayed the same weight for the rest of my life, I’d be fine.
Food always had control over me — I would think about it all the time. I would argue I’d been dieting for decades. I started a variety of programs though high school and my weight fluctuated, and in university, it really started to climb. By the time I was in medical school, I was almost 200 pounds. When I finished I was 260 and when I finished my residency I was 300.

Make no mistake, as a physician who studies this disease [obesity], I definitely know I had a genetic disposition. How we relate to food has a really complex physiology, but you can’t discount the environment I engaged in. I was a really sedentary person, specifically through residency and medical school. I was definitely someone who did not eat properly, which was fascinating because I knew what to eat.

The Final Straw: The only story I can really remember is that I was in residency and I bought a ticket for one of those home lotteries and won an elliptical trainer. I’d love to tell you I took the elliptical home and put it in my room and boom! But it was probably months before I got on it for five minutes and I thought I was going to die. And then I thought "I’ll just do five minutes again tomorrow." Within a few weeks I started to write down what I was eating, so I started to make gradual changes.

I didn't lose 176 pounds in three years — the bulk of my weight I lost was in the first four years (120 pounds) and the remaining 50 or so has been since then.

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The Plan Of Attack: Keep a food diary and exercise every single day. Also, you should weigh yourself at least once a week — I do it to see where I am. However, the scale is not a very accurate measurement, but that being said, it’s a really good place to start.

I also have rules. I try not to eat out more than once a week, but I try to make it a really nice time. I’m militant about food when I can be — I think of it like a disease.

The Food Element: I try to avoid refined carbohydrates, in fact at all costs. My diet consists primarily of healthy protein and lots of vegetables, probably seven to eight servings a day and three pieces of fruit.
But I’m not scared of fat — I think my diet is probably more of a Mediterranean based diet. I eat bread at a restaurant when it’s quality, and typically on Sundays when I’m not working, I go to this a cafe and have a macaron.

The Exercise Factor: My story isn't typical, not everybody loses 175 pounds and keeps it off. Not everybody goes from being really physically unwell to being a marathon runner. But slowly, five minutes became 10, 10 became 20, and within six months I was doing an hour a day. I also took up swimming and running.

The Current Day-To-Day: I bike to work and back every day -— an hour total with occasional loops through the park. I'm also training for a marathon.
There are days when I’m working late, and when I don’t have the chance to go for the run, I add an extra 20 minutes on the bike. I've made activity a part of my lifestyle now.

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