Dave Harper and Dale Drewery are not only romantic partners, they're keto diet partners as well. In 2013, the couple, who live in Vancouver and have been together for 22 years, decided to give the high-fat, low-carb ketogenic diet a try.

Six years and 40 or so pounds later, they're still going strong on keto. In fact, they recently published a book, BioDiet, that covers the science behind the super trendy plan, why it can improve overall health, plus practical tips on how to stick with it long-term.

Harper, a cancer researcher and kinesiology professor at the University of the Fraser Valley, tells Health that he and Drewery, who works as a health journalist, started the plan while he was researching the impact of diet on long-term health. 

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"I was introduced to the ketogenic diet in 2010 while hosting a radio program called Think for Yourself," Harper explains. Up until that time, he had been consuming what he refers to as the standard American diet, which is high in carbs.

Though he was never overweight, he said that his pre-keto eating habits resulted in weight gain over time. After learning about the keto diet through the show, Harper spent two years researching it. "What I liked about it was that it made much more sense to me given my considerable understanding of how the human body (and our metabolism) works," he says.

After getting the all-clear from his doctor to start the diet, he told Drewery about it, and she agreed to go keto with him. They both lost about 20 pounds each. Yet for them, the positive effects of the plan went way beyond weight loss. 

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“If there was any downside of going keto, it was that we had to buy new clothes because we both lost weight,” recalls Harper. "And while it's great to lose weight, it was the improvement in our health, our moods, and our energy levels that made us feel so fantastic."

Harper explains that a traditional carb-heavy diet can lead to three major health setbacks: obesity, insulin resistance, and inflammation. Each of these can in turn cause the others, he says, and that creates a cycle of disease and chronic illness.

"High carb diets lead to chronically high blood sugar, which causes chronically, abnormally high levels of insulin in the blood (called hyperinsulinemia)," Harper says. "Over time, this leads to insulin resistance, obesity, and inflammation: the axis of illness."

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Since keto is the opposite of a traditional diet—it's low in carbs rather than high-carb—it can help prevent the three setbacks, he says. “With keto, most people can reduce their incidence of chronic disease,” Harper adds. (It's important to check with your doctor before going on the restrictive diet, he advises.) 

Making the decision to try keto is one thing—but staying motivated to continue with it can be tricky, he acknowledges. One tactic to not fall off the wagon, he says, is to follow the diet with a partner.

“This isn't just a diet change, it's a lifestyle change. You're changing the way you shop, where you eat, when you eat, and more,” says Harper. "So it really does help when you have a partner doing it with you and keeping you accountable. The temptations are gone, plus you have the social support of each other."

Another tip is to prepare meals yourself as much as possible, so you use foods and ingredients that fit with the plan. Harper says he tries "to plan and make all my own meals, so that I know exactly what I’m eating.” His weekly grocery list includes plenty of veggies, high-fat organ meats like liver, plus high-fat oils, creams, and cheese.

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As for how to stay keto when you're away from home, Harper advises keeping keto-approved snacks close at hand. “I always have a bag of nuts with me when I’m on the go, in case I can’t find a keto-friendly meal around,” Harper says.

Ultimately, Harper stresses that if you're considering going on the keto diet, you should read up on it first. Also, focus on how it can improve your health. "Focus on the health benefits, because that will come with the weight loss," he says. 

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