What Are the Pros & Cons of the Keto Diet?


What if someone told you that you could eat cheese, bacon, avocado, peanut butter, heavy cream, full-fat yogurt, and dark chocolate and still lose weight?

You’d find it hard to believe, right?

Well, on the keto diet, you actually can – but there’s a catch.

The diet requires you to drastically reduce your carbohydrate intake. That means no refined carbs, very little fruit (with a few exceptions), and no rice, potatoes, whole grains, or legumes.

There’s a lot of nutrition, fiber, antioxidants, phytonutrients, and minerals in the starchy vegetables, fruits, and grains that aren’t allowed. For this reason, many health experts advise against the keto diet for the long haul.

Also, the keto diet’s unusually high fat and animal protein content runs counter to what many doctors and health organizations, like the American Heart Association, have recommended for decades, which adds a layer of controversy to the diet.

Still, the health benefits of keto eating appeal to many people, including world-class athletes such as NBA star LeBron James and former NFL quarterback Tim Tebow. Even though U.S. News & World Report ranked it as one of the worst diets of 2020, a recent survey of registered dietitians ranked it as the most popular diet in the U.S.

Hopefully, the information presented here will help you determine if the keto diet is right for you.

What Is the Keto Diet?

In a nutshell, the keto diet is an eating plan comprised mostly of fats, a reasonable amount of protein, and very few carbohydrates. When you give the body an abundance of fat and a negligible amount of carbs, some interesting things happen.


By drastically reducing carbohydrate intake, your body runs out of its preferred fuel of carbs, and eventually its glycogen stores, too. It then switches to burning fat for energy. This metabolic state is called ketosis.

When in ketosis, the liver converts stored fatty acids to ketones or ketone bodies, which are then used as fuel by the heart, brain, and muscles.

To achieve and maintain ketosis, most people need to limit their total carb intake to 20–50 grams per day and get an abundance of healthy fats.

A person following the keto diet aims to burn unwanted fat by pushing the body to rely on fat (rather than carbs) for energy. Ketosis promotes weight loss and a host of other health benefits.

While there are several versions of the keto diet, the standard keto diet is the most popular. The macronutrient breakdown of it is typically 70% fat, 20% protein, and only 10% carbs.

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Keto Pros

As was mentioned earlier, the keto diet offers some very compelling health benefits. Here are several of the most significant:

Weight Loss

When it comes to short-term weight loss, keto is king.

Comparing 23 different studies that tracked low carb and low-fat dieters for varying lengths (mostly six months or less), the low carb dieters lost on average 2-3 times more weight than low-fat dieters. What’s more, the low carb diets were more effective in reducing abdominal fat.

Unlike low-fat dieters, those on low carb diets don’t have to worry about caloric intake. The high-fat foods are incredibly satiating, which helps with adherence. Seeing results quickly can also be motivating.

Cardiovascular Benefits

Also evident in the low carb studies mentioned above, other health parameters associated with carrying excess weight improved as well. Low carb dieters showed improved blood sugar, blood pressure, and triglyceride and cholesterol level markers.

Brain Health

Some studies indicate that the ketones generated from ketosis provide neuroprotective benefits, which means they can strengthen and protect the brain and nerve cells.

Eating a low carb/high-fat diet has also shown improvements in low mood, feelings of anxiousness, and brain focus issues.


Eating a diet high in refined carbohydrates can alter the balance of gut bacteria and cause blood sugar to rise and fall significantly, both of which can adversely affect skin health. One study showed that by decreasing carb consumption, a keto diet could lessen acne problems in some people.


Keto Cons

The keto diet has several drawbacks and a few health risks that need to be carefully considered, such as:

Flu-Like Complications

After a few days on the keto diet, you may experience problems. These may include headaches, dizziness, fatigue, nausea, and constipation – often resulting from dehydration and electrolyte imbalances that occur, in part, as your body gets used to ketosis. However, these issues generally subside after a few weeks. Staying hydrated and getting sufficient daily amounts of sodium, potassium, and electrolytes can help.

Blood Sugar Issues

Although the keto diet has been shown to support healthy blood sugar levels, complications having to do with ketones and blood sugar may­­ arise.

Heart Health Concerns

Keto is a high-fat diet. If you consume too much saturated fat, your cholesterol levels can increase, especially LDL, which is linked to cardiovascular health issues. However, risks can be alleviated and cholesterol levels improved by choosing healthier fats such as mono- and polyunsaturated fats found in nuts, seeds, olives, and avocados.

Liver and Kidney Problems 

The liver and kidneys help your body process fat and protein. Some experts believe that the keto diet could overwork them. Also, a high intake of fatty animal foods can put you at higher risk for kidney stones.

Low in Nutrients and Fiber 

Keto limits a lot of high-fiber, nutrient-dense fruits, starchy vegetables, whole grains, and legumes. It may not provide enough of certain vitamins and minerals needed for optimal health.

Studies on the keto diet have found deficiencies in calcium, vitamin D, magnesium, and phosphorus. Additionally, unless one takes measures to eat plenty of leafy green and cruciferous vegetables, the keto diet can often be constipating and may even disrupt healthy gut bacteria.

Restrictive and Challenging 

The keto diet is highly restrictive. Carbohydrates normally account for at least 50% of the typical American diet. Adherence is challenging for many people.

Exacerbates Disordered Eating

Risk of disordered eating behaviors is common for keto dieters. Dieting, in general, can interfere with the joy of eating and simple daily activities, but a diet that’s as extreme and restrictive as keto can be particularly challenging for anyone, especially those with eating struggles.

Bottom Line

The keto diet delivers fast, short-term weight loss and excellent benefits in terms of managing healthy blood sugar levels.

However, the challenges of ketosis, and some of the potential health risks of the keto diet, underscore the importance of choosing an abundance of healthy fats (olive oil, coconut oil, avocado oil, nuts, and seeds), quality meats, and consuming plenty of low carb/high fiber vegetables to minimize issues.

Some people thrive on eating a low carb diet. However, for most people, keto appears to be too restrictive for the long-term. Also, health experts note legitimate concerns about a diet that eliminates so many healthy and important staple foods (grains, legumes, starchy vegetables, and fruits) essential to vibrant health.

As with any diet, it’s recommended that you consult a healthcare professional before starting a low carb diet (such as keto) or making any changes to your diet.

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Kim Henderson