Doctors who champion low-carb, high-fat diets go against the grain

Originally published on Jan 12, 2019 

When Dr. Carol Loffelmann wanted to lose her post-baby weight, she did what most of her colleagues suggest: she cut calories, ate a low-fat diet, and ramped up her exercise. 

Instead of dropping pounds, she gained them. 

"I was getting pretty frustrated," Loffelmann, a Toronto anesthesiologist, told White Coat, Black Art host Dr. Brian Goldman.

A colleague then suggested going 'paleo', a diet based on food supposedly eaten by early humans — meat, fish, vegetables and fruit, and excluding dairy, grains and processed food.

Lofelmann was sceptical. 

"I thought, 'All that saturated fat is going to kill you,'" she said — and, given her Dutch roots, she was not about to give up cheese. 

But she was curious about the science behind paleo and other similar diets. After reviewing studies, she tried cutting carbohydrates while at a five-day medical conference. So she ate only the 'middles' from her sandwiches and switched to salad instead of fries.

"My trainer was at my home the next day, and I opened up the door to her and she looked at me and said, 'What did you do?' And the only thing I did was drop those carbs."  

It was enough to convince her to stay with a low-carb high fat (LCHF) diet, of which one version is the popular keto diet, championed by celebrities such as Halle Berry and Kourtney Kardashian.  

All that chatter in my head around my weight just went quiet.- Dr. Miriam Berchuk, on using a low-carb, high fat diet 

"I am someone who was constantly thinking about sweets. Within a few days the cravings were gone. I wasn't feeling deprived," said Dr. Miriam Berchuk, a Calgary anesthesiologist.

"But most importantly, all that chatter in my head around my weight just went quiet."

High-fat diets a matter of debate

Both physicians are part of Canadian Clinicians for Therapeutic Nutrition (CCTN). Loffelmann is a founder, and Berchuk is the scientific advisor.

They believe so strongly that LCHF is beneficial for both weight loss and treating diseases related to obesity, their mission as part of CCTN is to spread awareness and acceptance of the diet.

That's a challenge, considering the diet contradicts some of the currently accepted thinking on nutrition.

The latest update of Canada's Food Guide, a draft of which was previewed this week, doubles down on whole grains and advises limiting saturated fat.

The goal of a ketogenic diet is to switch your body over to burning fat as a primary fuel source, rather than glucose.

Eating very few carbohydrates causes the body to produce molecules called ketones from fat, which the body burns instead.

That typically means eating around 5 per cent carbohydrates, up to 20 per cent protein and 75 or 80 per cent fat. 

It's that amount of fat, especially when it comes from saturated fat, that causes concern.

There is the concern that when the diet isn't well planned, you are likely to experience nutrient deficiencies.- Kortney Patriquin, dietician

Kortney Patriquin, a registered dietitian, looked at meal plans keto support groups posted online.

"It was like buttered cheese for breakfast!" she said.

Patriquin said that anyone going LCHF should consult with a registered dietitian, else they risk running into nutrient deficiencies.

More guidance on LCHF needed, urge advocates

Berchuk doesn't disagree with that advice. 

"At the moment because low carb diets aren't recognized as legitimate by the major health authorities [such as] Diabetes Canada, Heart & Stroke ... what ends up happening is there's just a void left, and people are left with no option but to go the internet — and sometimes they don't get great advice there."

Loffleman said she hears from colleagues that "not a day goes by" that patients don't come in and ask about the keto diet, so it's important that doctors find out how to support them. 

The other knock against LCHF is that patients are unlikely to stick with such a restricted diet.

But one Vancouver physician says in his case, sustainability is not an issue. 

Dr. Jay Wortman has maintained a low-carb, fat-rich diet for 16 years. Wortman, who is Metis, wanted help getting his Type 2 diabetes under control, and successfully did so by turning to a traditional Indigenous diet. 

"When I had my epiphany about low-carb, I was working in First Nations for Inuit Health for Health Canada and as you know the diabetes epidemic ... is devastating," said Wortman.

"It started to occur to me that this was due to their dramatic change in diet from their traditional healthy diet characterized by a minimal amount of carbohydrates."

Indeed, a recent study from McMaster University demonstrated a link between high-carb diets and an increased risk of heart disease.

Dr. Michelle Klassen was prompted to start researching keto-style diets when some of her patients told her they were finding success with it.

"They were following the Canada Food Guide, things weren't working. Their diseases were getting worse," the Calgary doctor said.

She now runs a support group for patients eating LCHF.

Listen to Calgary physician Michelle Klassen counsel patients who are using a low-carb, high fat diet. 

"I can't argue with what I'm seeing," she said. "We actually look at this as a treatment for diabetes, mostly Type 2 diabetes. I manage some hypertension with this."

Klassen understands why there is resistance within the medical community, but she remains adamant LCHF isn't a fad. 

She admits there's plenty more research to be done and acknowledges LCHF isn't the right for everyone.

Berchuk believes her colleagues are opening up, especially when presented with science. But she concedes any changes to dietary guidelines will take more time and advocacy. 

"I think those health-care providers who are bound by their organizations and by the guidelines put out by their organizations, they're anxious about breaking ranks. Right now there's probably nothing more contentious," said Berchuk.

"There's politics, and then there's diet."