A cancer researcher who's been on the keto diet for 6 years explains how he does it
- The ketogenic diet is becoming a popular way to lose weight.
- The high-fat eating plan has been shown to help manage Type 2 diabetes and epileptic seizures, and some scientists hypothesize that it could help make certain cancer treatments more effective.
- Anatomy and physiology professor David Harper has been on the diet for six years. Here's how it's been going.
Six years ago, David Harper considered himself relatively healthy.
The anatomy and physiology professor loved an occasional cookie, but he exercised often, cooked nutritious meals at home, and tried to stick to conventional nutrition advice: not too many calories, low amounts of fat.
But Harper started to realize that saturated fat may not be so bad, and that maybe it was the carbohydrates he ate that were causing him to pile on extra pounds and increasing inflammation.
"We've been telling people to eat the wrong diet for 40 years, and we've seen the results," Harper told Business Insider.
He's is convinced that carbohydrate-heavy, low-fat diets are a major reason we're seeing high rates of diabetes, high blood pressure, obesity, and cancer. That's because a diet high in sugar can quickly raise insulin levels in the body. Over time, those insulin spikes can lead to insulin resistance and eventually to long-term health issues like high blood pressure, Type 2 diabetes, inflammation, and obesity.
So years before the likes of LeBron James and the Kardashians figured out there might be some benefits to a low-carb, high-fat ketogenic diet, Harper gave it a try.
Harper lost over 20 pounds on a high-fat, low-carb diet
Trained in mathematical biofluiddynamics, Harper teaches anatomy, physiology, and pathology at University of the Frasier Valley in British Columbia. He said that's part of the reason the keto diet made sense to him.
"It was the knowledge that I gained through my career teaching anatomy, physiology, and pathology that led me to the conclusion that this is absolutely right, in terms of the way the human body works," he said.
Harper went on the diet with his wife to test out what it was like for a few months.
"Over 12 weeks I lost about 22 pounds of body fat," he said, adding that most of it was around his mid-section. He wasn't a big guy before - about 5'9" tall and roughly 177 pounds - but today he weighs 150 or so.
The reason the keto diet is effective for weight loss and some disease control is that it fundamentally shifts the way our bodies run. On a traditional diet, our bodies automatically reach for carbohydrates to burn first, before using fats, because carbs are quicker and easier to break down.
But if there are no carbs available, our bodies start burning fat as a primary fuel source and producing ketone bodies in the liver, which the body can turn into energy. This metabolic state, called ketosis, is what happens when someone is starving. But it's also how Harper's body works every day. His system relies on fats like butter, oil, and lard as a primary energy source instead of packing those fats on as in-case-of-emergency poundage.
Harper said he doesn't even feel hungry if he skips a meal or two.
Harper doesn't eat tons of meat, and hasn't given up wine
Harper said he often starts the day by eating high-fat yogurt topped with a few berries and some roasted nuts. Other mornings, his breakfast might be bacon and eggs with some tomato and avocado.
His sweet tooth is gone, he said. Instead, he gets hankerings for fatty foods.
"What I crave is butter," he said. "I like grass-fed butter. I could eat that stuff like cheese."
If he's out and about during the day, he might order a breve latte, which is made with cream instead of whole milk. Most keto dieters shy away from even the fattiest milk because it contains too many carbohydrates (specifically sugar) to be ketosis-friendly. Harper keeps a stash of nuts with him at all times when on the go.
[Read More: The tastiest, most surprising foods you can eat on the keto diet]
For lunch, he often opts for a salad with chicken or fish on top. The dinners he cooks are usually pasta-style dishes or maybe the occasional meat-and-potatoes type meal, except he replaces any potatoes or grain-based pasta with low-carb alternatives like cauliflower or squash. Often he tops the meal off with cheese. He avoids beans and apples, which are too high-carb to be considered keto, but sometimes has a glass of wine or munches on berries for a sweet treat.
"It's all real food that comes from plants, and I don't eat huge amounts of meat," Harper said.
If he does cook chicken, he keeps the fatty skin on, and the small cuts of steak he picks out are marbled with fat.
The keto diet is not a diet at all
Harper doesn't think the keto diet should be tried as a quick fix, and he's not a fan of keto "cycling": a practice that involves switching back and forth between a state of ketosis and meals with more carbs.
"You need to be committed, and you need to really say 'I've been on the wrong path for a long time and I'm willing to give up a lot of these foods that I really love, that I'm emotionally attached to, and I'm going to change to a different diet because that's going to provide better health,'" he said.
But a few disclaimers about the keto diet are in order. It's not for everyone - people with a history of kidney or liver issues and pregnant women can put themselves in severe danger if they try the diet. The plan should not be tried without consulting a professional.
Harper also said that many people may confuse going keto for an excuse to fill up on bacon and eggs every morning, but it really isn't. A proper keto diet is about 70-80% fat, with no more than 10-15% carbs. That means most people try to keep their carbohydrate intake below 50 grams a day and stick to only moderate amounts of protein.
Other kinesiologists think the keto diet could have dangerous effects on people's athletic performance, and it's tough to know what potential side effects a long-term high-fat diet might have for a healthy person, since we don't have any solid study results yet. Low-carb diets like keto can make it easy to neglect key nutrients like magnesium, calcium, and potassium that are found in fresh, high-carb foods like beans, bananas, and oats.
Ketogenic diets are, however, already a well established treatment to help control Type 2 diabetes and the plan has been used to reduce instances of childhood epileptic seizures for nearly 100 years. Some scientists also think the high-fat diet may hold promise for staving off Alzheimer's, and there are some early indications it might help improve certain cancer treatment outcomes when used in conjunction with drugs. (Harper is part of a research team that's investigating how the diet might help boost treatment in patients with breast cancer.)
But Harper doesn't think keto should be considered a fad diet.
"You can't do this halfway," he said. "You have to be all in, and all in forever."