The Ketogenic Diet: The Pros, The Cons, And The Risks

Ketogenic Foods

People adhering to the ketogenic diet will emphasize foods like:

  • Fats galore! Think avocados, olive oil, butter, and coconut oil.
  • Protein: Eggs, fish, poultry, beef, lamb… all the meats!
  • Non-starchy vegetables: Things like leafy greens, broccoli, cauliflower, and Brussels Sprouts.

The diet restricts foods like:

  • Full-fat dairy.
  • Medium-starchy vegetables like carrots, beets, peas, and potatoes.
  • Legumes (beans, lentils, peanuts).
  • Nuts and seeds.
  • Fruits.
Photo: AdobeStock/vaaseenaa
Photo: AdobeStock/vaaseenaa

The diet says to avoid foods like:

  • All sugars.
  • Grains, including oats, rice, and corn.
  • Legumes (beans, lentils, peanuts).
  • Foods made with flour.
  • Processed foods—if it comes in a bag or a box, forget it.

Ketogenic Diet Considerations

The “Keto-Flu”
While there are many avid supporters of the diet, most agree that when someone is first entering a state of ketosis they will experience symptoms known as the “keto-flu.” Carbohydrates help your body retain water, and your body will retain less water as you consume fewer carbs. It’s important that those on the ketogenic diet stay hydrated to ward off (as much as possible) the risk of constipation, fatigue, headaches, and cramps that are associated with the transition into ketosis and loss of electrolytes. These flu-like symptoms do eventually go away.

Photo: AdobeStock/
Photo: AdobeStock/

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The ketogenic diet comes with a risk of kidney stones, bad breath, cramps, and dizziness. The high prevalence of fats and animal products may also increase your cholestrol, though some sources say that the ketogenic diet improves cholesterol levels. Some dietitians feel that staying in ketosis regularly could harm the body because ketones are generally used as an emergency fuel source and are acidic. While a non-diabetic generally won’t go into ketoacidosis, acid may still build up in your system and cause harm.

Another critique is that the diet cuts out major food groups, which could make it hard to get proper nutrition. Some whole-grain and dairy foods are good for us, and severely limited options can affect sustainability.

Other Keto-Cons include:

  • Dry mouth
  • Increased urination
  • Digestion issues
  • Lack of research on long-term effectiveness. Some experts feel the diet is not safe or sustainable on a long-term basis.
Photo: AdobeStock/vladimirfloyd
Photo: AdobeStock/vladimirfloyd


Keep in mind that studies on the ketogenic are slim, and more information will be available as long-term studies are available. The diet is accepted as an effective treatment for epilepsy and may be beneficial in Alzheimer’s or other brain-related conditions.

The diet, if followed, can definitely result in weight loss so long as total calories consumed are less than calories expended—no diet can get around that principle. It may also increase blood sugar control (there are some people with diabetes who feel strongly about the diet’s ability to normalize blood sugar levels).

Other claimed benefits include:

  • Greater mental focus.
  • Increased energy.
  • Improved satiety and appetite control.
  • Better skin/reduced acne.
Photo: AdobeStock/diego cervo
Photo: AdobeStock/diego cervo

Final Thoughts

The main critique of the ketogenic diet, as with many diets that quickly gain a following, is that the claims outstrip the truth. An Australian documentary prompted backlash from the medical community when a chef claimed that the diet could treat autism, cancer, and diabetes.

The Mayo Clinic cautions dieters that while keto may be beneficial to those with epilepsy, others should consider the high saturated fat content of the diet and choose a diet with better balance and more sustainability. Another considering the diet should do so after talking to their doctor and having a plan in place to make sure nutrition needs are met.

Photo: AdobeStock/
Photo: AdobeStock/

Perhaps high-quality studies will prove the long-term safety and health benefits of the ketogenic diet. Or perhaps ketogenic enthusiam will fade like that of diets before it. Perhaps, a hundred years from now, people will be throwing bread out the window again. Time will tell!

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