Ketogenic Diet vs Paleo Diet: A Serious Look at These Fad Diets and My Words of Caution

Ketogenic Diet vs Paleo Diet: A Serious Look at These Fad Diets and My Words of Caution

I will preface this discussion by saying that as a Dietitian, I am not a fan of any trendy or fad diets no matter how promising they may seem. Not because there are not some very real benefits to many of them, but rather for two very important reasons:

1.     People tend to be very quick to jump onto popular “fads” because they want a “quick fix” to their health issues (or more often for weight loss).

2.     Most of them time, people aren’t doing proper research about these diets and are, therefore, often not following them healthfully and with caution.

I will say one thing very loud and clear: when it comes to health, there is no quick fix. Period. You may follow a fad diet for a few months and lose weight. You’ll be happy for a moment, but chances are, after you fall off the wagon (for any number of reasons that are bound to happen), you will very quickly regain all – if not more – of your weight back. And you’ll be left feeling even more frustrated than you were before. Not to mention, if you’ve been following a specific diet without the proper planning or understanding about it (which 90% of people I encounter fall victim of), you could also put your body at risk for nutritional deficiencies or other internal organ damage. This will put you in worse shape coming out of it than you were before. I will work hard to help my patients avoid these potential damages at all costs whether popular or not.

Your body is unique. Your body has it’s own nuances and intricacies that can be very different from your friends – even others in your family. Seeking to know your body’s specificities and distinctive inner-workings is the key to your own health and longevity. Lasting health success comes from a series of small, consistent and committed steps each and every day that work for your body.

All that said, if you do in-depth research from credentialed sources, you might find elements of certain diets that you like and that work for you and your body. In that vein, I would like to offer my professional overview of these two specific diets that seem to be especially popular right now.

Keto Diet

The Background

The Keto diet was originally discovered as a method for helping to manage seizures in people with epilepsy. It is still used for these purposes today. When used outside of this health condition, the keto diet is fairly efficient at reducing body fat fairly quickly because once a person reaches a states of adequate ketosis, they will burn their fat as fuel.

The Science

Our bodies generally utilize glucose as its primary source of energy. Glucose is most commonly found in carbohydrate sources of food such as bread, cereals, pastas, pastries and some starchy vegetables. Our body will not burn any excess body fat until any remaining glucose has been completely utilized first. This might seem like a simple feat, but carbohydrates make up over 50% of our diet.

Once glucose is no longer present, our body will then create ketone bodies which is the product of the breakdown of fat as fuel. After a few days of this, our bodies will eventually reach a state that we coin “ketosis.” Biologically, reaching a ketogenic state was what saved our species from long states of starvation, not only to be able to switch our energy usage to our fat reserves, but also because ketone bodies can cross the blood-brain barrier, which is critical if we want our brain and Central Nervous System (CNS) to continue to function without glucose. 

What is the macronutrient breakdown?

On a ketogenic diet, fat is the primary source of fuel; therefore fats will make up the bulk of the diet (nearly 70%). Proteins will make up approximately 25% of the diet, and carbohydrates generally won’t be more than about 5% (but this will vary on the person and on the level of ketosis they are trying to reach.

The pros:

The speed at which a person will officially enter a ketogenic state will vary by age, activity level, and diet. But once you have reached ketosis, you will burn actual body fat fairly quickly. Also, in prolonged states without carbohydrates and sugar, our bodies tend to adapt to not eating them. Therefore we also tend not to crave these foods either. And because fats are much longer molecules than carbohydrates and proteins, they take much longer for our body to breakdown. This means people following a ketogenic diet tend to stay fuller longer.

The cons:

There are several real issues with prolonged usage of the ketogenic diet.

1.     Most people don’t follow it correctly. In my experience with patients following this diet, they believe that they should be eating all proteins, and so many eat mostly animal sources of protein which can be incredibly harmful to our digestive organs. We need the same amount of protein (from animal or plant-based sources) on the keto diet as in a normal diet. If a patient does, in fact, know the difference between protein and fat, many are choosing to eat unhealthy sources of saturated and trans-fat instead of the healthier versions of mono-unsaturated fat. This could not only potentially lead to heart issues in the future, but it could also cause gallbladder issues in the short-term too.

2.     Many people don’t include any fiber. Because plant-based fruits and vegetables have varying percentages of carbohydrates, people tend to steer clear of them almost entirely for fear of losing their ketogenic state. Our bodies need fiber. And with carbohydrates from grains excluded, fruits and vegetables are some of our best and richest sources of fiber on this diet. Both soluble and insoluble fibers help to keep our digestive system moving. If we eat little or no vegetables or other sources of fiber (especially for long periods of time), we risk severe damage to our digestive tract.

3.     May cause nutritional deficiencies. Whenever we eliminate an entire macronutrient like you are in the ketogenic diet, the higher the risk of nutritional deficiencies. There are a great many nutritional benefits to eating carbohydrates including high fiber content as well as other important vitamins and minerals.

4.     May cause internal acidity and inflammation. Prolonged states of ketosis can lower our body’s pH to be more acidic, especially with diets high in animal proteins. When our bodies are in a regular and constant state of acidity, we increase internal inflammation. Chronic inflammation can be the cause of a variety of health issues over the long run.

Summary:

The Keto Diet is not a one-sized fits all approach, and it’s absolutely not the “cure-all” for people’s weight woes. If you are looking to follow a keto diet, I recommend doing it for a short period of time only to kick start your weight loss journey. Adhering to a keto diet for more than a month or two can have harmful effects on your internal organs and may be generally hard to sustain. If you do decide to try a keto diet, plan well. Fill your plate with healthy, monounsaturated fats including nuts, seeds, avocados, olives, olive oils, etc. Eat low-carbohydrate sources of plants and vegetables with every meal. Drink plenty of water! If you have any history of gallbladder, thyroid, kidney, pancreas or liver issues, this is likely not the diet for you.

The Paleolithic Diet

The Background:

Humans today are being faced with a variety of health issues (including heart disease, diabetes and cancer, to name a few) that our caveman ancestors never seemed experienced. I would argue that many of our caveman and more recent ancestors had many other non-health-related issues that caused them early deaths that we no longer face. But for the sake of this argument, people who are interested in the Paleo Diet are interested in eating more like our early ancestors because they believe our bodies are more biologically included to eat foods higher in protein and fat. Not to mention, the standard American diet has been well-documented to be a large cause of the health issues we face today, which could mean we are genetically mis-matched for our modern diet.

The Science:

The Paleo diet’s main suggestion is to avoid any/all refined sugars and processed foods. It emphasizes whole foods, especially those from plant-based sources like nuts, seeds, berries and vegetables. It also significantly reduces and/or completely eliminates known highly inflammatory foods such dairy and gluten. While those following a strict Paleo diet may significantly reduce their carbohydrate and grain intake (which I don’t often recommend), it is otherwise – quite simply – a very healthy, whole diet. And there is ample research supporting the elimination of processed foods and refined sugar on reducing the chances of a variety of unfavorable health outcomes like Diabetes, hypertension, obesity and more. Also, any diet that encourages lots of vegetables and plant-based foods also has quite a bit of positive science to back it.

What is the macronutrient breakdown?

The macro breakdown on the paleo diet can vary depending on the person, and is not nearly as strict or extreme as the keto diet. It encourages about 30% calories from protein, about 40% from fat and 30% from carbohydrates (mainly from plant-based sources). This is lower in carbohydrates than a standard diet, but much more reasonable (and likely more sustainable) than the keto diet.

The pros:

Any diet that is lower in processed foods and refined sugar is going to have positive health outcomes. The diet encourages fats from mono and poly-unsaturated fats which are known to have benefits for our brain and heart. It is more sustainable than the keto diet in that you can still have some carbohydrate sources, but ideally from whole plants or starchy vegetables.

The cons:

·      Elimination of grains. Those following this diet strictly may entirely eliminate grains, which have so many health benefits, as mentioned above.

·      Many people eat too much protein. If not planned carefully, I’ve seen people eat too much protein and not enough fat or carbohydrates. There is still a limit to the amount of protein, especially from animal sources that is allotted on this diet.

·      Not all cavemen ate the same. Yes, we all descend from cavemen, but our specific ancestors may have come from different geographical regions! The foods that cavemen in South America thrived on are not the same type of crops that cavemen in Northern Europe would have eaten. It would be much more beneficial to do a little digging into your own ancestral history and learn about the crops that your great-great-great grandparents ate. This is likely going to give you a better sense of what foods work better for your physiology.

Summary:

I like the Paleo diet when it is used as a template, rather than a hard-and-fast rule. Most people should take a hard look at their own intake of processed and refined foods. These are the root cause of a great number of our health issues. Any any time we can reduce inflammatory foods like dairy and gluten, you’re likely doing your body good too. I don’t suggest eliminating grains as entire food group. But following a moderate version of the Paleo diet may be a great and sustainable option for many.