Keto Diet: Healthy Or Hazardous?

The ketogenic diet is a low-carb, high-fat diet that is often used for weight loss. While it may be effective for this purpose, there are several health risks associated with it. These include nutrient deficiencies, digestive issues, impaired bone health, and an increased risk of chronic diseases such as heart disease, cancer, and Alzheimer's. The diet may also be unsafe for pregnant women and individuals with kidney disease. As such, it is important to consult a healthcare professional before starting the keto diet.

May cause digestive issues and changes in gut bacteria

The keto diet can cause digestive issues and changes in gut bacteria. The diet restricts carbohydrates and increases fat intake, which can lead to a lack of fibre and an excess of bile in the digestive system. This may result in constipation and other gastrointestinal issues such as acid reflux, bloating, and diarrhoea.

The keto diet can also negatively impact gut health by reducing the diversity of gut bacteria and changing the types of bacteria present. A 2019 study found that high-fat diets might cause inflammation of the digestive tract, a decrease in beneficial fatty acids, and unfavourable changes in the gut microbiome. However, some studies have shown that a keto diet may have positive effects on gut bacteria, but more research is needed to confirm this.

The potential for digestive issues and changes in gut bacteria on the keto diet is concerning because gut health is linked to overall health. A healthy gut may boost immunity, improve mental health, and decrease inflammation. Therefore, it is important for individuals considering the keto diet to be aware of these potential risks and take steps to mitigate them, such as by increasing their fibre intake and consuming fermented foods.

To prevent and manage gastrointestinal symptoms while on the keto diet, it is recommended to eat more fibre, take probiotic supplements, and ease into the diet. Fibre-rich, keto-friendly foods include non-starchy vegetables like broccoli, artichokes, and collard greens, as well as avocados and nuts. Fermented foods such as sauerkraut and kimchi can also help improve digestion and reduce constipation or diarrhoea. Staying hydrated is also important, as adequate water intake helps move things along in the digestive tract.

While the gastrointestinal effects of the keto diet may be short-lived for some individuals, others may experience more long-term or severe symptoms. It is important to consult a doctor if you are experiencing severe or persistent abdominal pain, blood in your stool, or diarrhoea that occurs more than six times a day or disrupts your sleep.

May lead to nutrient deficiencies

The keto diet restricts several food groups, including nutrient-dense fruits, whole grains, and legumes. As a result, it may not provide the recommended amounts of vitamins and minerals.

Some studies suggest that the keto diet does not provide sufficient calcium, vitamin D, magnesium, and phosphorus. A study that evaluated the nutrient composition of common diets revealed that very low-carb diets like Atkins, which is similar to keto, provided sufficient amounts for only 12 of the 27 vitamins and minerals that the body needs to obtain from food.

Over time, this may lead to nutrient deficiencies. Notably, guidelines for clinicians who manage people on a very low-calorie keto diet for weight loss recommend supplementing with potassium, sodium, magnesium, calcium, omega-3 fatty acids, psyllium fiber, and vitamins B, C, and E.

The nutritional adequacy of the keto diet depends on the specific foods consumed. A diet rich in healthy low-carb foods, such as avocados, nuts, and non-starchy vegetables, provides more nutrients than a diet of processed meats and keto treats.

A high-fat/carb-restrictive diet like keto may lack the following vitamins and minerals necessary for a healthy diet: vitamin B1, vitamin B6, vitamin B7, vitamin B12, calcium, iron, magnesium, and phosphorus. These are all essential nutrients that the body needs to function properly.

B vitamins are necessary for turning food into energy. Calcium, magnesium, and phosphorus are crucial for strong bones. Iron is needed to carry oxygen and help the body grow and develop properly.

Additionally, very-low-carbohydrate diets may lack vitamins, minerals, fiber, and phytochemicals found in fruits, vegetables, and whole grains. Low-carbohydrate diets are often low in thiamin, folate, vitamin A, vitamin E, vitamin B6, calcium, magnesium, iron, and potassium. In the absence of multivitamin supplements, individuals on low-carbohydrate diets are at risk of nutritional deficiencies.

Even when consuming only nutrient-dense foods, a 4:1 ketogenic diet is reported to have multiple micronutrient shortfalls, often lacking in vitamin K, linolenic acid, and water-soluble vitamins excluding vitamin B12.

May cause dangerously low blood sugar

The keto diet is a low-carb, high-fat diet that has been associated with several health benefits, including weight loss, improved blood sugar control, and reduced seizure frequency in individuals with epilepsy. However, following a keto diet also has some potential risks and side effects that should not be ignored. One of the most concerning risks is the possibility of causing dangerously low blood sugar levels, especially in individuals with type 1 diabetes.

Low blood sugar, or hypoglycemia, is a condition where your blood sugar drops below the normal range, typically below 3.9 mmol/L or 70 mg/dL. While this condition is more common in individuals with diabetes, it can also occur in people without diabetes, including those following a keto diet. The keto diet restricts carbohydrate intake to less than 50 grams per day, which can result in lower blood sugar levels. This is because carbohydrates are the body's primary source of glucose, and when there is a lack of carbohydrates, the body's blood sugar levels can drop.

Individuals with type 1 diabetes who follow a keto diet may be at a higher risk of experiencing low blood sugar episodes, also known as hypoglycemia. Hypoglycemia can be life-threatening and is characterised by symptoms such as confusion, shakiness, fatigue, and sweating. A study found that individuals with type 1 diabetes who followed a ketogenic diet for over two years experienced a median of almost one low blood sugar event per day. This is because individuals with type 1 diabetes are typically dependent on carbohydrates to maintain their blood sugar levels, and when they reduce their carbohydrate intake significantly, it can lead to hypoglycemia.

Even individuals without diabetes can experience hypoglycemia due to the keto diet. This is because the keto diet can deplete the body's glucose stores in the liver, which are used to maintain blood sugar levels. Additionally, intense exercise without proper carbohydrate replenishment can further lower blood sugar levels. Alcohol consumption can also increase the risk of hypoglycemia, as it interferes with the body's ability to produce glucose.

It is important to monitor blood sugar levels closely when following a keto diet, especially for those with type 1 diabetes or other medical conditions. Eating small amounts of carbohydrates, such as fruit, is usually enough to resolve hypoglycemia symptoms. However, if symptoms persist or blood sugar levels remain low, it is crucial to seek immediate medical attention. While the keto diet can be beneficial for some, it is essential to be aware of the potential risks and side effects and to consult with a healthcare professional before starting any new diet.

May damage bone health

The keto diet may damage bone health, according to some studies. The diet's high acidity has been linked to a decrease in bone mineral density, which is essential for bone strength. For example, a study of 29 children with epilepsy found that 68% had lower bone mineral density scores after six months on the keto diet. Similarly, research on 30 elite race walkers showed that a ketogenic diet for 3.5 weeks resulted in higher levels of blood markers for bone breakdown compared to a high-carb diet.

The keto diet's restriction of carbohydrate-rich foods means that it can be challenging to meet daily fibre needs, which may negatively impact digestive health and, in turn, bone health. The diet's focus on animal-based and high-fat foods may also increase the risk of kidney stones and metabolic acidosis, further impacting bone health.

While the existing research suggests a potential link between the keto diet and impaired bone health, more extensive and long-term studies are needed to confirm these findings and understand the full range of effects on bone health.

May increase the risk of chronic diseases and early death

The ketogenic diet has been linked to an increased risk of chronic diseases and early death. The diet's restriction of carbohydrate-rich foods and encouragement of red and processed meats have been associated with a heightened risk of heart disease, cancer, type 2 diabetes, and Alzheimer's disease.

The high intake of animal products on the keto diet can lead to a more acidic urine and a higher risk of kidney stones. This can be particularly dangerous for those with chronic kidney disease, as the acid buildup in the blood can worsen the progression of the disease.

Additionally, the keto diet's restriction of fruits, vegetables, whole grains, and legumes can result in vitamin and mineral deficiencies. This may further increase the risk of chronic diseases and negatively impact overall health.

The long-term effects of the keto diet are still being studied, but the available evidence suggests that the potential risks of the diet may outweigh the benefits for most individuals.

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