Last winter I was talking with a friend about what I needed to do to stay healthy out on the court. (At 35 it’s not getting any easier.) When the topic of nutrition came up, he urged me to go see his naturopath, Dr. Suneil Jain, here in Arizona. Now, I have tons of people looking after my well-being – coaches, doctors, trainers, my wife – so I’m always skeptical about seeking new advice. But I’m glad I went.

Jain pushes a whole-foods diet, one that consists of lots of raw fruits and vegetables. Okay, but I’m not giving up my steak dinner. Then Jain started talking about how important it is to cut sugar out of your diet. What? My first thought was that that would be impossible, but he made a convincing case. Jain told me that the average American eats about 92 grams of sugar a day, when the human body needs only about eight grams for energy, an amount that should always be satisfied through natural sugars from fresh fruits, vegetables, and grains. Refined sugars, he told me, impair your immune system. In fact, one teaspoon of refined sugar suppresses our white blood cells for up to six hours, making it a lot easier to catch a cold. I really can’t afford colds during the season, so that’s all I needed to hear: I cut out refined sugars cold turkey. No M&M’s at the movies, no energy bars, no Gatorade – I even had to be more careful when going to Jamba Juice, because sometimes they use sugar-filled juice from concentrate. After a few months, I stopped craving sugar entirely.

The difference was instantaneous: I slept better, I recovered from workouts more easily, and I had more energy. When we started training camp in September, we were doing two-a-days – four or five hours on the court – and I never got sore. Even more telling is the fact that this summer I traveled all over the world for my foundation, bringing team sports to war-ravaged countries. I was missing out on sleep and still training the whole time, but I never got sick. I’ve got to think it’s because sugar wasn’t wearing me down.

No doubt, this lifestyle is not easy – sugar gets sneaked into just about everything, so I have to pack my own food. But it doesn’t bother me, because the way I feel is so worth it.

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