Keto Side Effects: How Long Do They Last?

The ketogenic diet, or keto, is a high-fat, low-carbohydrate diet that has become increasingly popular in recent years. While it may lead to initial weight loss, this is primarily due to the loss of body water that accompanies lower carbohydrate intake rather than fat loss. The keto diet is associated with various side effects, including nutrient deficiencies, impaired intestinal function, increased bad cholesterol, impaired kidney function, and birth defects. These side effects can last from a few days to a few weeks, and in some cases, may have long-term health consequences. For example, long-term adherence to the keto diet has been linked to an increased risk of heart disease, kidney stones, and certain types of cancer. Therefore, it is important to carefully consider the potential risks and side effects before starting the keto diet or any other restrictive diet.

Keto flu

The "keto flu" is a collection of symptoms that can occur when someone is new to the keto diet, caused by the body adapting to ketosis. Symptoms include an upset stomach, dizziness, decreased energy, and mood swings. These side effects usually pass within a few days to a few weeks.

The keto diet is a high-fat, low-carbohydrate diet that encourages the body to use fat as its primary energy source instead of glucose. To achieve ketosis, the diet requires a person to eat 75% of their calories from fat, 5% from carbohydrates, and 15% from protein. This is a significant shift from a typical diet, where normally only 20-35% of calories come from fat.

The transition to ketosis can be challenging for the body, and this is reflected in the symptoms of keto flu. Feeling tired and experiencing low energy is a common side effect of the keto diet, as the body gets used to producing and using ketones for energy instead of glucose. The body and brain usually rely on glucose for fuel, so this transition period can result in fatigue and dizziness.

In addition to fatigue, other common symptoms of keto flu include an upset stomach and mood swings. The shift in diet can affect the digestive system, leading to stomach discomfort. The change in fuel sources and the body's adjustment to ketosis can also impact mood and energy levels, resulting in mood swings.

It is important to note that the keto diet is not a sustainable or realistic long-term diet for most people and can lead to nutrient deficiencies and increased risk of heart disease, kidney stones, constipation, and social isolation. The restrictive nature of the diet makes it challenging to follow correctly, and it may not be suitable for those with certain medical conditions, such as diabetes, or for women who are pregnant or planning to become pregnant.

While keto flu symptoms typically resolve within a few days to a few weeks, it is essential to listen to your body and consult a healthcare professional if symptoms persist or become concerning.

Nutrient deficiencies

This can lead to deficiencies in vitamins and minerals, such as vitamins B1, B6, B7, B12, A, and E, as well as calcium, magnesium, iron, and potassium. B vitamins are essential for turning food into energy, while calcium, magnesium, and phosphorus are crucial for strong bones. Iron is needed to carry oxygen and support the body's growth and development.

The keto diet is also typically low in fiber, which is necessary for healthy intestinal function and the production of beneficial colonic short-chain fatty acids.

Additionally, the keto diet may be lacking in phytochemicals, which are not typically included in multivitamins and for which specific intake targets have not been established.

To mitigate nutrient deficiencies, it is important to be aware of any deficiencies you may already have before starting the keto diet. You can also focus on including high-quality meats, dark leafy greens, broccoli, avocados, and full-fat yogurt in your diet.

Kidney function

The keto diet is a high-fat, low-carb approach to eating that has become one of the most popular ways to lose weight. However, it is important to be aware of the risks before giving it a go. One of the biggest dangers of the keto diet is that it can put stress on the kidneys and may even cause kidney stones.

How the Keto Diet Affects Kidney Function

When on the keto diet, the body's primary source of energy comes from burning fat rather than carbohydrates. This means that the body is not getting the vegetables and fruit that are required in a more traditional diet. Eating more protein and animal fats generates more acid in the blood, which can lead to a condition called acidosis. Acidosis increases the risk of developing painful kidney stones by lowering urine pH and urinary citrate levels, which are protective, while also increasing urinary calcium excretion.

High Dietary Acid Load and Kidney Health

High dietary acid load, generated by the consumption of high amounts of animal fat and protein, is associated with albuminuria (losing protein in urine) and the onset of chronic kidney disease. Research has also linked the keto diet to an increased decline in kidney function for those who already have chronic kidney disease. When you eat a high-protein diet, the kidney must work harder due to increased blood flow to the filtering unit of the kidney, called hyperfiltration, which leads to the progression of chronic kidney disease.

The Keto Diet and Metabolic Acidosis

The keto diet can also worsen metabolic acidosis, which is a common complication of chronic kidney disease and can ultimately affect bone and muscle health.

Alternative Diets for Kidney Health

For those with kidney disease, one of the best ways to maintain a healthy weight is to adopt a healthy lifestyle with balanced and portioned meals. This includes adequate amounts of protein, carbohydrates, fat, fiber, and other micronutrients. Restricting or reducing salt intake, particularly if you have high blood pressure, and ensuring proper hydration will also alleviate stress on the kidneys.

Consult a Specialist

If you have or are at risk of kidney disease, it is important to consult with a physician or nephrologist to discuss lifestyle changes and dietary modifications. Your dietary restrictions will depend on your renal health, and a specialist will be able to advise you on foods that are beneficial for kidney health, such as the renal diet.

Weight loss

The keto diet is a high-fat, low-carbohydrate diet that leads to the generation of ketones, a type of chemical that the liver produces when it breaks down fats. The diet is popular for weight loss, but its long-term effects are not well understood.

Short-term weight loss

When starting the keto diet, people often experience a satisfying initial weight loss. However, this is a short-term result from the loss of body water that accompanies lower carbohydrate intake, not fat loss. This is because when we eat carbs, the energy that we do not use immediately is stored as glycogen molecules, and each gram of glycogen is stored with 3 grams of water attached to it. When you cut down on carbs, you quickly use up your glycogen stores, losing that water weight.

Long-term weight loss

The keto diet is not intended to be adhered to long-term, nor is it uniquely effective for weight loss. Studies show that after 6 months, a ketogenic diet does not lead to significantly higher weight loss than other weight loss approaches.

In a study of 83 obese patients, a 24-week ketogenic diet resulted in significant weight loss and a decrease in body mass index. However, it is important to note that this was a small study and may not be representative of the general population.

In another study, obese women on a low-carbohydrate ketogenic diet lost significantly more weight over six months compared to those on a low-fat diet. However, this study also had a small sample size and may not be generalizable.

Sustainability

The keto diet's restrictive nature makes it unlikely that people will follow it correctly, with over 50% of people failing to adhere to a ketogenic diet in many medical studies. Even if weight loss is achieved in the short term, it is difficult to maintain, and weight gain may come back, and you may gain more than what was lost.

Cardiovascular risk

While the keto diet may lead to weight loss, it may also increase the risk of cardiovascular disease. In a study of young, fit CrossFit athletes, following a keto diet for 12 weeks led to an average weight loss of 6 pounds but a 35% increase in "bad cholesterol" (LDL-C). Typically, LDL-C levels drop when weight is lost. LDL-C has long been associated with cardiovascular risk because it forms arterial plaques (a cholesterol build-up in the inner lining of arteries). Emerging research that followed people for 12 years has now directly linked long-term ketogenic dieting with a 2x higher risk of heart disease or other negative cardiac events.

Heart disease

The ketogenic diet is a high-fat, low-carbohydrate, and adequate-protein diet. While it may be beneficial for short-term weight loss, there are concerns about its impact on heart health.

Cardiovascular Risks

The keto diet's extreme carbohydrate restrictions may lead people to avoid vegetables and fruits, which are rich in dietary fiber that helps protect the heart. The diet may also result in the overconsumption of saturated fats, which can increase the risk of heart disease.

The keto diet has been linked to an increase in "bad" LDL cholesterol levels, which can clog arteries. Additionally, the vitamin K in leafy greens may interfere with the anti-clotting drug warfarin, commonly taken by heart patients.

Pre-existing Heart Conditions

For those with pre-existing heart conditions, the keto diet may not be safe. It could interfere with certain medications and may not be suitable for those with conditions involving the pancreas, liver, thyroid, or gallbladder.

Alternative Approaches

Instead of restrictive diets like keto, a sustainable, whole-food diet is recommended. The Mediterranean diet, rich in good fats like omega-3s from fish and unsaturated fats from avocados and nuts, as well as fiber-rich whole grains, is often advised for optimal heart health.

While the keto diet may lead to short-term weight loss, its impact on heart health is less clear. It may increase the risk of heart disease due to its high saturated fat content and restriction of heart-healthy foods. For those with pre-existing heart conditions, the keto diet may interfere with medications and is not recommended without medical supervision.

A balanced approach, such as the Mediterranean diet, is generally recommended for optimal cardiovascular health.

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