7 reasons you shouldn't do the keto diet long-term

  • The keto diet has become popular as many people claim it can help with weight loss.
  • The diet, however, might not be best for long-term health as the eating habits it promotes might lead to heart rhythm problems.
  • Eating a diet high in fat and low in carbs might also make exercising more difficult.

The ketogenic diet has become popular with people looking to lose weight and improve their health. It involves significantly reducing carbohydrate intake while increasing the amount of fat and protein you eat. This puts the body into a state called ketosis, where fat is burned for energy instead of carbs.

The diet has plenty of fans and there is evidence it can help with weight loss by increasing satiety. There may, however, be risks to following a ketogenic way for an extended period of time. Though researchers do not know for certain the long-term effects of the keto diet, there has been research done on the long-term effects of consuming high-fat, low-carb diets.

INSIDER consulted with medical experts and nutritionists to find out if there are any reasons you shouldn’t stick with the keto diet long-term.

Cutting out carbs long-term has been linked to heart rhythm problems

New research presented by the American College of Cardiology has linked low-carb diets to an increased risk of developing atrial fibrillation (AFib).

The study compared the medical records of almost 14,000 people over 20 years and found that people who get a low percentage of their daily calories from grains, fruits, and starchy vegetables are significantly more at risk of developing AFib.

This condition causes the heart to beat irregularly and puts sufferers at five times the typical risk of stroke and heart attack.

Though the research does show a relationship between carb intake and AFib, it doesn’t show clear cause and effect. More investigation is needed into whether cutting carbs can have a negative effect on your heart health.

Your ability to exercise might suffer

One of the central premises of the ketogenic diet is that switching the body’s main energy source from carbohydrates to fat is a positive change. In reality, however, this benefit may depend on how active you are.

“Biologically, the body prefers to burn carbohydrate for fuel and store fat, especially during periods of physical activity. This is because it spends less energy burning carbs for fuel than it does burning fat,” registered dietician Rachel Fine told INSIDER.

If you’re supplying the body with inadequate amounts of carbohydrates, physical performance and exercise ability can suffer as the body struggles to maintain energy needs while breaking down fat, explained Fine. This can make you feel sluggish during workouts and can mean the keto diet isn’t a good long-term fit for athletes or people with highly physical jobs.

People with gallbladder problems should avoid eating high amounts of fat for long periods of time

The gallbladder stores and concentrates bile, which is made by the liver. Bile is essential for fat metabolism. A high-fat diet can aggravate existing gallbladder disease (GBD) and may increase a person’s risk of developing GBD.

“Especially if your gallbladder has been surgically removed, you may have trouble digesting all the fat you eat on the keto diet. Weight gain, bloating, and other digestive discomforts would be the first signs you would notice with this,” said Gittleman.

The symptoms of a poorly functioning gallbladder might not be evident until you increase your fat consumption. If you notice digestive problems after limiting carbs and increasing fat intake, it might be a sign that the keto diet isn’t a good fit for you long-term.

Being keto long-term may lead to vitamin deficiencies

Followers of a strict keto regimen might opt out of consuming carbohydrate-rich fruits and vegetables in an effort to keep their carb counts within a ketogenic range. Unfortunately, focusing solely on limiting carbs can lead to vitamin deficiencies in the long-run.

“The keto diet is often lacking in water-soluble vitamins and may result in deficiencies with long-term use. Those vitamins include all B-vitamins, which are essential for the health of the nervous system and energy metabolism. Vitamin C is also water-soluble and is well-known to support the immune system and healthy skin and hair,” registered dietician Cathy Posey told INSIDER.

Whole grains, beans, legumes, and fruits like bananas and oranges are rich in B and C vitamins but can be high in carbs. Lower carb, vitamin-rich options include Brussels sprouts, spinach, broccoli, raspberries, and blueberries. If you’re determined to stay on the keto diet long-term, you may also want to use vitamin supplements to make sure you’re getting everything you need to stay healthy.

Read more:10 subtle signs you have a vitamin deficiency

A long-term keto diet could have a negative impact on your gut and digestion

Many nutrient-dense and fibre-rich foods such as quinoa, beans, lentils, fruit, brown rice, and sweet potatoes are not permitted on a keto diet due to their higher carbohydrate content. For many people, excluding foods higher in fibre can lead to digestive issues like constipation and diarrhoea.

Additionally, restricting higher-carb foods like starchy vegetables and whole grains may not promote good gut health.

“Many of the plant-based foods limited on the keto diet are good sources of prebiotic fibres. Prebiotics feed our probiotics, the beneficial bacteria in our gut. This is essential for the health of our microbiome, which has been shown to be heavily involved in supporting our immune system and reducing inflammation,” registered dietician Melissa Mitri told INSIDER.

Focusing on eating fat-rich foods might compromise your health long-term

Bacon eggShutterstockThere’s a difference between ‘good’ fats and ‘bad’ fats.

All fats are not created equal. Unfortunately, some people may see the ketogenic diet’s emphasis on high-fat foods as a free pass to adopt unhealthy eating habits, such as over-indulging in processed meats and saturated fats.

“Many people follow a keto diet without regard to the type of fat they are consuming. All fats are high in calories, but saturated fat and trans fat raise the “bad” LDL cholesterol in your blood and can cause plaque to build up in your arteries,” said Fine.

Posey also told INSIDER that people on the keto diet often don’t make enough of an effort to eat fats that benefit brain and cardiovascular health or to choose fats that are unrefined or unprocessed. This can mean that sticking to a keto diet long-term can actually increase your risk of cardiovascular problems or high cholesterol if you’re not eating the right kinds of foods.

Read more:There’s a big difference between good and bad fat – here’s how to pick the best heart-healthy fats

Rather than consuming large amounts of saturated fats such as butter, ghee, palm oil, coconut oil, and bacon fat, keto dieters might want to consider focusing on unsaturated fats such as those found in avocado, nuts, olive oil, and fish. When done correctly, there is evidence that following the keto diet may improve cardiovascular health.

You might not want to do the keto diet long-term if you have a history of pancreatitis or high triglycerides

The ketogenic diet typically involves replacing carbohydrates from low-fat sources like grains, fruits, vegetables with greater amounts of fat from both plant and animal sources. This means that people who have medical conditions affected by fat intake should avoid following the keto diet, especially in the long term.

“High triglycerides circulating in the blood for a prolonged period of time can lead to acute pancreatitis. The high-fat keto diet is a known cause of acute pancreatitis because it causes an increase in circulating fats,” author and nutritionist Ann Louise Gittleman, Ph.D., told INSIDER.

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