Beware: Bad Keto's Negative Impact On Your Body

The ketogenic diet is a low-carb, high-fat diet that has been used since the 1920s as a treatment for epilepsy. Today, it is advertised as a quick weight-loss solution and a remedy for various health issues, from infertility to type 2 diabetes. While the keto diet can be effective for rapid weight loss, it also has several potential side effects and complications that can negatively impact your body and overall health. These include digestive issues, nutrient deficiencies, kidney problems, increased risk of chronic diseases, and negative effects on bone health and athletic performance.

Dehydration and loss of electrolytes

The keto diet is a low-carb, high-fat diet that puts the body into a state of ketosis, where it burns fat instead of sugar for fuel. While this diet can be safe and effective for weight loss and improving overall health, it can also lead to dehydration and electrolyte imbalances.

Causes of Dehydration and Electrolyte Loss on Keto

When on a keto diet, the body produces ketones to burn fat for energy instead of glucose. This process leads to the loss of water and electrolytes, which can result in dehydration. Carbohydrates usually help the body retain water and sodium, so eliminating them from your diet can cause you to lose necessary electrolytes such as sodium, magnesium, potassium, and calcium.

Additionally, the keto diet is often high in salty processed foods, which can further contribute to dehydration as the body flushes out more sodium when insulin levels are low. The risk of dehydration is particularly high when first starting the keto diet, as the body undergoes significant changes in how it handles water and electrolytes.

Symptoms of Dehydration and Electrolyte Loss

Dehydration and electrolyte imbalances can lead to various unpleasant symptoms, including:

• Dry mouth and throat
• Fatigue and weakness
• Dizziness and lightheadedness
• Muscle cramps
• Headaches
• Keto flu
• Constipation
• Increased thirst and hunger
• Confusion
• Poor judgment
• Seizures

Preventing and Managing Dehydration and Electrolyte Loss on Keto

To prevent dehydration and electrolyte loss while on the keto diet, it is crucial to increase your water intake and incorporate electrolyte-rich foods and drinks into your diet. Here are some tips to help you stay hydrated and maintain proper electrolyte levels:

• Start your day with a glass of water, and drink around eight glasses of water throughout the day.
• Keep a full glass of water nearby to remind yourself to drink regularly.
• Use a tracking cup or download a water-tracking app to monitor your daily water intake.
• Include other hydrating liquids such as low-sugar broths, juices, sports drinks, and popsicles.
• Eat whole foods like leafy vegetables, nuts, seeds, avocados, cucumbers, and celery, which have a high water content and are rich in electrolytes.
• Consume keto-friendly foods that contain electrolytes, such as leafy greens, avocados, nuts, beef, chicken, eggs, spinach, salmon, and almonds.
• Use salt/electrolyte tablets, lite salt (which has a higher potassium-to-sodium ratio), or simply add more salt to your food.
• Try mineral water, which can provide supplemental magnesium and calcium.
• Monitor your urine color; it should be pale yellow or clear. Dark yellow urine is a sign of dehydration.
• Avoid dehydrating substances like alcohol and caffeine.
• Slowly transition into the keto diet to prevent keto flu symptoms and electrolyte imbalances.

Kidney problems

The keto diet can put stress on the kidneys and may lead to kidney stones. This is due to the high intake of animal proteins and animal fat, which can cause your blood and urine to become more acidic, leading to an increased excretion of calcium in your urine. This combination makes you more susceptible to kidney stones, while high uric acid can increase your risk of gout.

The keto diet can be especially dangerous for people with kidney disease. Weakened kidneys may be unable to remove the acid buildup in the blood that results from animal foods. This can lead to a state of acidosis, which can worsen the progression of chronic kidney disease.

Higher-protein keto diets may also hasten kidney failure and cause other medical problems in patients with kidney disease. The average keto diet consists of 1.2-2.0 g/kg/d of protein, which is considered technically high.

Additionally, lower-protein diets are often recommended for individuals with chronic kidney disease, while the keto diet is moderate to high in protein.

One study observed that among children following the keto diet as a treatment for epilepsy, 13 out of 195 subjects developed kidney stones.

If you're considering the keto diet, it's important to speak to your doctor first, especially if you have kidney disease or other medical conditions.

Nutrient deficiencies

The keto diet can lead to nutrient deficiencies, as it restricts or eliminates many nutrient-rich foods. Whole grains, fruits, and vegetables are limited or cut out on the keto diet, which can lead to a lower intake of important vitamins and minerals.

A person on the keto diet may miss out on folate, thiamin, and vitamins A, B6, B12, C, E, and K. These vitamins and minerals are essential for body functions and development related to bones, gums, metabolism, and red blood cells.

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

Additionally, the keto diet may not provide enough protective dietary components such as phytochemicals, which are not typically found in multivitamins.

The lack of variety in the keto diet can put individuals at risk of deficiencies in micronutrients, including selenium, magnesium, phosphorus, and vitamins B and C.

It is important to be aware of any existing nutrient deficiencies before starting the keto diet, as eliminating certain foods can worsen these deficiencies and cause additional health concerns.

Digestive issues

The ketogenic diet is a low-carb, high-fat diet that can lead to digestive issues and changes in gut bacteria. Here are some ways in which the keto diet can affect digestive health:

Low Fibre Intake

The keto diet eliminates high-carb foods like fruits, starchy vegetables, grains, and legumes, which are also high in fibre. Fibre is essential for maintaining bowel regularity and protecting against digestive disorders. Insufficient fibre intake can lead to constipation and other digestive issues.

Altered Gut Microbiome

The keto diet may also alter the gut microbiome, which plays a crucial role in digestion, immune function, mental health, and disease prevention. Some studies suggest that a high-fat diet can increase inflammation, reduce beneficial fatty acids, and negatively impact the composition of gut bacteria. However, other studies have shown inconsistent results, and more research is needed.

Diarrhea and Gastrointestinal Issues

The keto diet can cause diarrhea and other gastrointestinal (GI) problems. This may be due to the body's difficulty in adjusting to the high-fat content of the diet or increased dairy consumption. The high-fat and low-carb content can also lead to nausea, bloating, and other GI symptoms.

Dehydration

The keto diet can lead to dehydration, as the body breaks down fat and produces ketones, resulting in more frequent urination. Dehydration can cause constipation, cramps, and other digestive issues. It is important to stay hydrated and drink enough water to maintain proper body function and digestive health.

Nutritional Concerns

The keto diet restricts many nutrient-dense foods, including fruits, vegetables, grains, and legumes. This can lead to a shortage of vitamins, minerals, and phytochemicals, as well as reduced fibre intake, further contributing to constipation and digestive issues.

While the keto diet can lead to weight loss and other potential benefits, it is important to consider the possible negative impacts on digestive health. Consulting with a healthcare professional or gastroenterologist before starting the keto diet is recommended, especially for individuals with existing medical conditions.

Bone health

Lifestyle habits, especially diet and exercise, can influence your peak bone mass by approximately 20 to 40%. A well-formulated keto diet emphasizes the consumption of protein and nutrient-rich vegetables, which are important for bone health and overall health. However, the keto diet has been associated with a decrease in bone density and an increase in bone breakdown.

A 2020 study published in Frontiers in Endocrinology found that a ketogenic diet may impair markers of bone health. The study involved 30 elite race walkers who followed either a high-carb, low-fat diet or a low-carb, high-fat keto diet for three and a half weeks. The keto group showed decreased markers for bone metabolism and formation and increased markers of bone breakdown. While the marker for bone breakdown returned to normal after restoring carbohydrate availability, markers of bone formation and metabolism did not.

Another study published in Nutrition in 2016 found that a very-low-carbohydrate ketogenic diet had no significant effect on bone mineral density (BMD) and bone mineral content (BMC) in obese adults. However, the study also reported a minimal decrease in total body BMD, and patients who did not receive a calcium supplement during the diet had a BMC reduction.

A systematic review published in Front Endocrinol (Lausanne) in 2023 found no significant changes in BMD after a ketogenic diet. However, the review also reported that ketogenic diets cause alterations in vitamin D levels, growth factors, and a high "acid load" via ketone bodies, which contribute to an increased risk for BMD loss.

While the evidence on the effects of a keto diet on bone health is limited and inconclusive, it is important to prioritize bone health as poor bone health increases the risk of fracture and frailty later in life. If you are considering a keto diet, it is recommended to consult with a healthcare professional and ensure you are receiving adequate amounts of vitamins and minerals, such as calcium and vitamin D, to support bone health.

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