It’s surprisingly common nowadays for people to hear about a diet, decide to follow it, but have little understanding as to how or why. I would say at least a quarter of the people I talk to who claim to be on a specific diet aren’t actually following it, simply from lack of understanding.

So to start the new year I decided to dig into the diet I see this with the most, the Ketogenic (otherwise known as Keto) diet.

What is it?

The Ketogenic diet is actually one of the first instances of a “Diet” to the extent that we know them today. Its first use goes all the way back to 1912 when doctors discovered that an extremely low carb diet reduced seizures in epileptic patients. The diet was notoriously difficult to follow since patients were allowed about 15g of Carbs (1 slice of toast) per day, and that’s including fruits and vegetables! The real kicker, was that the majority of patients on these diets saw weight loss, spurring the introduction of the Atkins diet around 1958.

How does it work? (short version)

The body uses carbohydrates to keep blood sugar at regular levels, but something unique happens when carbs are nearly eliminated. In order to keep blood sugar adequate the body uses an alternate process where it takes amino acids and fat and converts them directly into energy, small amounts of glucose, and chemicals known as ketone bodies. These ketone bodies then become the primary fuel source of the brain instead of glucose, a process called ketosis.  Since fat is used as a major fuel, many people see reduced body fat and weight loss on this diet. (source)

Has it changed in 100 years?

Yes! This is something that few people are aware of. The diet experienced renewed interest starting around 2003 when a study found that some patients on a traditional Keto diet could slowly increase their carbs and maintain ketosis. This led to what is now coined the Modified Atkins Diet, thus sparking a rise in public interest around 2008. No joke! This new version is far less strict though still difficult for many to maintain. (source1) (source2)

How to follow it?

Everyone reaches ketosis at a different level of carb intake, but the basic formula is 60% Fat, 30% Protein, and 10% Carbohydrates by weight. In a 1700 calorie diet this would look like 79% of calories from fat, 17% of calories from protein, and 4% from carbohydrate. Checkout the KetoCalculator if you want personal suggestions.

Does it require supplements?

Given this diet is usually 1500-1700 calories and the macronutrient ratio is unique, it requires the addition of a multi-vitamin, calcium, and vitamin D (source)

How to tell if you’re in ketosis?

Aside from a lengthy set of labs from your doctor, the only way to tell is by obtaining some KetoStix or if you want to be really precise and have a Blood Glucose Monitor you can use Precision Keto Strips.

Where to find more on the diet?

If you’re looking to dig into what to expect as well as possible adverse effects take a look at Ketogenic Diets or if you’re looking for specific recipes take a look at The Keto Cookbook both of which are great resources with oversight by Dietitians.

 Are there concerns with this diet?

To date there are only a handful of side-effects that have been researched. The first is a reduction in bone mineral density seen in children which could similarly affect adults (source3). The second is an increase in kidney stones, likely a result of the calcium interaction affecting bone density. And lastly, some studies have noticed an elevation of fats in the blood and reduced arterial function (source4) though these were shown to be reversible.

All in all I would say it is a fascinating diet from a medical standpoint and is being researched for its affects on reducing cancer formation as well as reducing damage from traumatic brain injury. I would probably not recommend it as a lifelong diet aside from individuals who suffer from seizures but there seems to be little risk on a short term basis.

If you’d like to see the excerpts from source3 and 4 take a look at the bottom. They are behind paywalls for most people.

Happy New Year! Be good to each other.

– Joshua Iufer, RD

*Source3:  Children eating such diets show reduced growth and lower bone mineral density (BMD). In previous experiments, it has been shown that rats fed (Low Carb High Fat) diets displayed reduced longitudinal growth and lower (Bone Mineral Density) as a result of impaired bone formation.

*Source4: “A gradual decrease in carotid distensibility and an increase in LDL-C, apoB and the TC:LDL-C and LDL-C:HDL-C ratios were seen at three and 12 months of (Ketogenic Diet) treatment. These differences were not significant at 24 months.”