What is a ketogenic diet?

The pros, cons, and facts about the ketogenic diet

So you believe following a ketogenic diet is a great way to rid excess pounds while still being able to feast away on butter and heavy cream. Sounds ideal doesn’t it?  However, before you head to the store to buy out any and everything high in fat, read on.  There are varying opinions on this way of eating for weight loss and not all of it is good.

What is a ketogenic diet?

The ketogenic diet took off in the 1920’s when it was discovered that following this high-fat diet was helpful to children with epilepsy.  In some children who follow this diet, it can help control seizures.  

How does it work?

Normally, our bodies rely on carbohydrates for energy or calories.  Our body absorbs carbs in the form of glucose which is the body’s main source of fuel.  But if you were to stop eating carbs, then the body turns more to fat as its main source of energy in a process called ketosis.  So now fat becomes your fuel. 

Ketosis is a metabolic state that has allowed humans to survive during periods of famine.  When we are not consuming sufficient carbohydrates, the body will begin to break down fat which produces a byproduct called ketones.  Ketones can provide energy for the brain when glucose is scarce.  A person can achieve ketosis by fasting or by strictly limiting carbohydrate intake to less than 20 to 30 grams per day (normally, the human body requires at least 130 grams of carbs each day).  Since a person has severely reduced their intake of carbs, they increase their intake of fat to about 70 to 80% of total calories with the remainder mainly coming from protein.  Carbohydrate intake is restricted to as low as only 2-4% of calories as compared to a standard diet which provides about 45-55% of calories from carbs.

The desired ratio when following a ketogenic diet is consuming 3 or 4 grams of fat for every 1 gram of carbohydrate or protein. 

What types of foods are allowed on a ketogenic diet?

One word – fat.  This means foods like bacon and butter, heavy whipping cream, mayonnaise, and oils.  A sample daily food intake might include eggs with olive oil and avocado on the side for breakfast, leafy greens, salmon, nuts and olive oil for lunch, and steak, greens, vegetables, and oil for dinner.

What foods are not allowed?

One word – carbohydrates.  This means all breads, pasta, grains, cereals, and sweets. 


Will a person lose weight following this diet?

The answer is yes but it takes eating to the brink of being extreme.  One reason why a person will lose weight is that the body is relying burning fat for fuel.  Plus eating all that fat makes you less hungry and less likely to overeat. 

This may all sound well and good but, whenever a weight loss diet recommends excluding an entire food group like carbs, this is a red flag.  Because it is a restrictive eating plan limiting fruits, many vegetables, grains, and other fiber-filled foods, it can result in nutritional deficiencies.  Many healthy carbohydrate foods provide our best sources of various vitamins, minerals, anti-oxidants and phytochemicals.  It is strongly advisable to be taking a vitamin-mineral supplement if on this diet.

Due to the lack of fiber when on a ketogenic diet, it’s very likely to have problems with constipation.

There is also lack of research on the long-term effects of a ketogenic diet in people.  We don’t really know how following this diet for a lengthy amount of time may affect the body.  Another concern with a long-term adherence to this diet is due to the high levels of nitrogen excretion during protein breakdown and the negative consequences on renal or kidney functioning.  Loss of bone mineral content also is a concern of following a ketogenic diet that could lead to osteoporosis.

On additional fact – eating this way for very long can get very old, fast.  Very few people are able to maintain eating a high-fat diet for a sustained length of time when they are severely limited on food choices. 

Take home message

The ketogenic diet is a very restrictive way of eating that most people cannot stick with for very long and is not recommended for weight loss. Anyone with heart disease or diabetes definitely should avoid this diet.

The one good thing about the ketogenic diet is that when a person reduces more of the not-so-healthy sugary carbs such as cakes, pies, or cookies, and replaces them by eating more healthy fats like nuts, avocados, and olive oil, this can be good.  Healthy fats – without going to extremes – are good for us and provide valuable nutrients.

The key is always to consume a well-balanced diet that allows all foods from each food group.  And when it comes to eating carbs high in fiber and whole grains and combining them with fat – this is the best of both worlds and will be far more successful at helping you reaching a healthier body weight in the long run.