Contemporary Diets: Which One Is Right for You — Keto

Are you confused about the differences and potential benefits between popular diets? Wondering which one might be best for you?

This is the fourth in a five-part blog series navigating contemporary diets, their philosophy, the science supporting each one, and the potential drawbacks. Previously I highlighted Paleo, Veganism and the DASH Diet. This post’s focus is the Ketogenic Diet and I’ll be covering the Mediterranean diet in my last post in this series.

Follow along and see which one is right for you!

#4: The Ketogenic Diet

The ketogenic diet is one of high fat, moderate protein and severely restricted carbohydrates. A common keto ratio is:

• 70% fat

• 20% protein

• 10% carbs

There are some other variations, but carbs are always quite low percentagewise. This contrasts sharply with the USDA’s recommendations of:

• 45-65% carbs

• 20-35% fat

• 10-35% protein

That’s quite a difference in both fat and carbs. Let’s break that down into calories, assuming a person is eating 2000 calories a day to maintain a healthy weight.

USDA KETO
Carbs = 225 - 325 g Carbs = 50 g
Fat = 44 = 78 g Fat = 156 g
Protein = 50 - 175 g Protein = 100 g

That’s a huge difference in carbs and doesn’t take long to accumulate 50 grams of net carbs. Net carbs are the total amount of carbohydrates minus the fiber. Fiber is technically a carbohydrate, but it’s undigestible – and super good for your gut microbiome.

Side Note: Carbs and protein both have 4 calories per gram while fat has 9 calories per gram. While not considered a macronutrient, alcohol has 7 calories per gram but doesn’t contribute any essential nutrients.

Basically, the difference between keto and the typical American diet relates to the choice of fuel source for energy – swapping carbohydrates for fat. I haven’t heard a better explanation than what nutrition guru and pioneer of the primal/paleo movement Mark Sisson offers, so I’ll quote him directly here:

“…consider fat and ketones the big logs in a campfire. Heat them up carefully and they’ll keep you warm for hours – not much smoke. Glucose is like kindling – burning quickly with lots of smoke.”

This translates to longer periods of satiety with fat as the body’s primary fuel source versus the constant craving for more carbohydrates if the body is relying primarily on carbs for fuel. And ketones, they are chemical compounds that are a metabolic byproduct of fat breakdown in the absence of glucose from carbs. Hence the name Ketogenic Diet.

So, what does one eat when following a keto diet? Lots of avocado, coconut and olives – both the fruits and the oils. And lots of poultry with the skin, fatty fish (herring, mackerel, salmon and sardines are among the fattiest fish), red meats, full fat diary (butter, cheese, heavy cream), bacon and eggs. Veggies are rather limited to those that are lowest in carbohydrates: leafy greens, cabbage, broccoli, Brussels sprouts and cauliflower as well as asparagus, bell peppers, celery, cucumber, mushrooms and tomatoes. Fruit is occasional and enjoyed in very small quantities. In a strict keto diet, sugar, all grains, legumes, starchy vegetables and processed foods are eliminated.

Hydration is very important on a ketogenic diet. Carbohydrates hold water in the body. When you decrease carbs, you lose water. In addition, with the drop in carbs, the kidneys increase excretion of water and sodium. Adequate water intake and use of electrolytes can prevent dehydration. Dark urine is a sign you need more water. The goal is urine that is pale yellow.

Strengths

There is quite a bit of scientific research supporting a ketogenic diet specifically for those with epilepsy that is not responsive to medication and for lowering HbA1c and for weight loss for type II diabetics due to the restriction of carbs. It can also be supportive for those undergoing chemotherapy for cancer as it starves the cancer cells while providing energy to the body’s healthy cells. It can also be helpful for those in the early stages of Alzheimer's especially for those who do not have the APOEe4 gene. This gene is known for disrupting the metabolism of fats in the brain and contributing to brain plaques.

Potential Drawbacks

The high fat ketogenic diet isn’t for everyone. Not everyone processes that amount of fat well – especially someone who has had his/her gallbladder removed. The gallbladder is the organ that stores bile, which is key in metabolizing fat. The limited amount of fiber has the potential to negatively impact the microbiome, which can lead to a variety of uncomfortable digestive symptoms. Food high in fiber include fruits, vegetables, legumes and some whole grains – the majority of which are excluded with a ketogenic diet. And the lack of fruits and limitation of vegetables is concerning to this holistic nutritionist. Fruits and vegetables are packed with nutrition, especially vitamins, minerals and antioxidants. Another potential drawback is that compliance is difficult. Eating out can be a challenge. And it’s just not sustainable as the level of restriction is too limiting for many people.

In my opinion, the ketogenic diet is best when temporary – perhaps 3-4 months. Then transitioning to a paleo diet can provide more balance. Since paleo avoids all grains and possibly legumes, overall carb intake will be lower, processed foods and sugars would still be eliminated, but there’s no strict limitation on healthy fruits and vegetables.