What are the Pros and Cons of the Keto Diet?

Few eating trends have captivated popular attention in recent years as much as the Ketogenic Diet. In our previous two articles, we’ve discussed the diet’s historic start as a treatment for epilepsy and disclosed what it takes to follow it correctly.

But is the ketogenic diet worth following? Like all eating strategies, there are some serious pros and cons to weigh before beginning. By the end of this article, you’ll be one step closer to understanding whether going keto is right for you.*

*The information on this site is informative in nature and should never be construed or interpreted as a substitute for medical advice or an endorsement for this diet. No information on this site is intended to be instructional and should not be considered or used as medical diagnosis or treatment. Each person is different, and the way your body responds to a particular diet may be significantly different from the way other people respond. You should speak with your physician or healthcare professional before starting any diet or exercise program.

Quick Keto Overview

As we touched on before, the ketogenic diet is an eating strategy where you power your system on fat, rather than carbohydrates. A standard ketogenic diet consists of 75% fat, 20% protein, and 5% carbohydrates, though there is some room for modification to meet your personal goals. If you eat 2,000 calories per day, this breaks down to about 167 grams of fat, 100 grams of protein, and 25 grams or fewer of carbohydrates.

By minimizing your carbohydrate intake and consuming healthy fats instead, the ketogenic diet puts your body into ketosis. This is a metabolic state where the liver converts fats into acids called ketone bodies that it uses for fuel. This process simulates fasting conditions to switch up your energy supply. Naturally, there are some significant side effects from this process; some positive and others less so.

Pros and Cons of the Ketogenic Diet

What will the ketogenic diet do to your body? Below are some of the diet’s most common reported side effects - both positive and negative.


There’s a reason why the ketogenic is so popular today; it has been shown to produce the following changes in health.

Can Help You Lose Weight

Research reveals that the diet significantly impacts the amount of body fat you metabolize for energy, and following a diet based around high-fat foods tends to boost satiety so that you want to snack less during the day. This keeps calorie counts under control, which can lead to weight loss and an overall change in your body composition.

May Improve Cognitive Functioning

The ketogenic diet has long been understood to affect brain functioning. The high fat content in the diet helps reduce inflammation that triggers nerve pain in the brain, and research shows that overweight patients who go on the diet experience fewer migraines than they did previously.

Studies are also speculative that the diet can reduce the symptoms or hinder the development of neurological diseases like Alzheimer’s and Parkinson’s, and children on the diet often exhibit better concentration and fewer ADHD symptoms than their peers. Further evidence shows that powering the brain on ketones can improve the outcome after traumatic brain injuries, though most research today has only looked at rat populations.

May Slow Various Cancers

Evidence shows that following a keto diet might slow the spread of tumor cells and even suppress their growth altogether.

May Reduce Inflammation from High Blood Sugar

The ketogenic diet helps reduce your insulin levels, which prevents it from triggering various health problems. There is also evidence that the diet can reduce your overall insulin sensitivity, which makes it easier for your body to process carbohydrates effectively.

Helps You to Kick the Sugar Habit

Sugar addiction is a serious problem for millions of people but following the ketogenic diet can may make it easier to fight off cravings because each meal leaves you satiated. As the diet restricts your carbohydrate intake to 25 grams per day, you’ll cut your sugar intake down to almost nothing, which makes it easier to quit the habit altogether.

May Increase Female Fertility

Over 10 percent of American women under 44 struggle to conceive or carry a pregnancy to term. Many find that following the ketogenic diet seems to help some of the underlying issues with fertility. The eating strategy positively affects weight and insulin levels, and it can reduce the hormonal effects of polycystic ovarian syndrome (PCOS).

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No diet is perfect, and the ketogenic diet has its share of downsides.

Most Initial Weight Loss is Water

It’s not uncommon to experience dramatic weight loss when you first go keto, but for many these losses can’t be sustained and they rarely last. These initial losses are primarily attributed to water weight from burning your glycogen stores. If you add carbs back to your diet, some of those pounds will return.

Long-term Research is Limited

Despite the diet’s popularity today, little is known about the effects of the Ketogenic diet on your health over time. This leaves researchers with more questions than answers about its effectiveness after years or decades of commitment. There isn’t conclusive evidence about whether Ketogenic followers will regain the weight or suffer other health consequences, meaning that following the eating method today might potentially put you at risk in the future.

The Diet May Trigger Brain Fog

Your brain is primed to run on glucose and limiting this supply can affect your mental functioning. This is because your body struggles to transition from using an available energy supply to making its own, which can affect brain functioning in ways that lead to memory loss, headaches, slower cognition, and general ‘brain fog’.

These effects are usually temporary, and they dissipate once the brain adjusts to burning ketone bodies instead. However, those who are predisposed to mental health issues like anxiety and depression might feel these effects more acutely, meaning that the ketogenic diet might not be the best choice for them.

Going Keto Limits Your Fruit and Starchy Vegetable Intake

Entering ketosis requires you to restrict particular fruit and vegetable consumption, which may make it difficult to consume enough vitamins, minerals, and fiber to stay healthy. Many high-carb whole foods are considered very healthy, so following the diet for the long-term could lead to health problems if you aren’t careful to keep your nutrient levels in check.

Easy to Accidentally Eat Unhealthy Fats

The Ketogenic diet prioritizes fats above all other macronutrients, but it can be hard for beginners to know which ones to invest in. Many people who try to go Ketogenic fail to choose quality fats like those that come from plants and organic or grass-fed animal products. Filling up on canola oil or other “cheap” fats can be damaging for your health in the long run.

Potentially Dangerous for Those at Risk of Eating Disorders

The ketogenic diet, as with some other diets, requires scrutiny of each meal you eat, which can pose a problem for those with a history of disordered eating. Following the eating plan can become obsessive for some people and categorizing so many foods as “off limits” can lead to negative associations with food that are physically and mentally damaging. Likewise, failing to follow the diet perfectly might lead to feelings of guilt and inadequacy, all of which should be carefully weighed before beginning.

Might Trigger Kidney Stones

Between three and ten percent of people who follow the ketogenic diet for months at a time to develop kidney stones, partly because of its lack of fiber. You can reduce your risk by ensuring that you stay hydrated and eating those foods that are keto approved with higher fiber content.

Potential for Ketoacidosis

If you put yourself in ketosis for too long, you risk developing excessively high levels of acids in your blood, which leads to a condition called ketoacidosis. This condition can leave you queasy, short of breath and mentally confused. In extreme cases, it might lead to hospitalization.

Might Cause Digestive Distress

When you first transition to keto eating, the high-fat, low-carb diet has the potential to lead to digestive problems like diarrhea or constipation. The symptoms typically disappear after a few weeks, but they can be alarming at first.

Bad Breath is Common

One temporary yet inconvenient side effect of entering ketosis is “fruity” breath. This happens because your body is breaking down acetoacetic acid, which many people say produces a similar smell to nail polish. Your urine while you’re in ketosis often smells the same way.

Ketosis Could Affect Your Athletic Skills

The evidence is mixed about how the ketogenic diet affects athletic performance, and some people find that this eating strategy hurts their results. Athletes that are looking to maximize their power may struggle to put on weight and improve their strength with a low carbohydrate diet, but endurance athletes that need to sustain their energy for long periods of time might become more efficient if they fuel themselves on fat stores. Even so, the diet is more difficult for athletes to follow than less active people because of the difficulty of adequately powering yourself without carbs.

You Might Get the “Keto Flu”

As your body acclimates to the ketogenic diet, you might go through a period of transition that leaves you feeling weak and exhausted. Followers of the eating plan call this the keto flu, and it can leave you feeling weak, lightheaded, irritable, mentally slow, constipated, and lethargic. The symptoms usually subside within a few days to a few weeks.

Dos and Don’ts of the Keto Diet*

If you’re ready to try following the ketogenic diet, then you need to set yourself up for success from day one. Below are some dos and don’ts to keep in mind when you first begin.

*The information on this site is informative in nature and should never be construed or interpreted as a substitute for medical advice or an endorsement for this diet. Each person is different, and the way your body responds to a particular diet may be significantly different from the way other people respond. You should speak with your physician or healthcare professional before starting any diet or exercise program.


  • Stick with healthy fats like eggs, avocado, and extra virgin olive oil
  • Eat low-carb greens as much as possible to maximize your nutrient intake
  • Eat real food made from whole ingredients (nothing processed)
  • Source organic, grass-fed animal products as much as possible
  • Stay hydrated- it helps offset the loss of fiber in your diet
  • Keep a food journal to track how you feel over time
  • Consider a modified keto diet if the restrictions are too severe
  • Consult with your doctor before beginning if you have underlying medical conditions
  • Consider nutritional coaching to ensure you follow the eating plan correctly
  • Replace your electrolytes by drinking bone broth


  • Avoid eating fast food as much as possible (the fat content is low quality, even in keto-friendly meals)
  • Don’t avoid looking at nutritional information before you eat- most foods have more carbs than you would expect
  • Avoid “bad fats” like corn, soybean, canola or hydrogenated oil
  • Avoid any processed food listed as low-fat, as most manufacturers make up for the lack of flavor with extra sugar (carbs)
  • Don’t overeat. The high satiety of keto-friendly food might mean that your place looks emptier at mealtimes than it did before. Avoid overstuffing yourself out of habit.
  • Don’t stress about calories. There’s little reason to monitor your amounts if your macronutrient ratios are where they should be.
  • Avoid consuming too many nuts or dairy products, as they are typically calorie-dense and are easy to overeat.

Up Next: What Does a Keto Meal Plan Look Like

Our next blog post will show you how to create a keto meal plan. We’ll dive into a keto-friendly food guide and offer a 5-day meal plan for those that interested in getting started. Stay tuned!

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Article Categories: Holistic Nutrition , Health Tips
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