Keto Vs. Mediterranean Diet: Which Is Better For Weight Loss?

The ketogenic (keto) and Mediterranean diets are two popular eating plans that have been studied for their potential health benefits and weight loss effects. Both diets are often used by those looking to lose weight, but which is more effective?

The keto diet is a high-fat, low-carbohydrate diet that was initially introduced as a treatment for epilepsy. It involves drastically reducing carbohydrate intake, which puts the body into a state of ketosis, where it burns fat for energy instead of sugar. This can lead to quick weight loss, but it is more restrictive and may be harder to stick to long-term.

On the other hand, the Mediterranean diet is inspired by the traditional eating patterns of countries like Italy, Spain, and Greece. It includes plenty of fruits, vegetables, whole grains, beans, legumes, and healthy fats, with moderate amounts of poultry, seafood, and dairy, and limited red meat, processed foods, and added sugar. This diet is less restrictive and more balanced, making it easier to incorporate into daily life and maintain long-term.

While both diets can promote weight loss, evidence suggests that the Mediterranean diet is safer, more sustainable, and potentially more effective for long-term weight management.

The Mediterranean diet is more sustainable and safer for long-term weight loss

The Mediterranean diet is a more balanced and inclusive eating plan that can be incorporated into daily life. It is less restrictive and does not require strict macro tracking, making it more manageable and less likely to lead to disordered eating behaviours. This diet generally encourages a high consumption of plant-based foods, healthy fats, and moderate amounts of animal protein, with an emphasis on whole foods over processed options.

On the other hand, the keto diet is highly restrictive and challenging to follow. It involves drastically reducing carbohydrate intake to achieve ketosis, a state where the body burns stored fat for energy. While this can lead to quick initial weight loss, it is not often sustained long-term. The keto diet is also associated with several potential downsides, including the "keto flu," which can cause fatigue, nausea, and brain fog. Additionally, there are concerns about the long-term health impacts of consuming a very high-fat, low-carb diet, and it may increase the risk of vitamin and mineral deficiencies.

Furthermore, the Mediterranean diet has been consistently ranked as the number one diet for healthy eating by health and nutrition experts. It has been associated with reduced risk for various health conditions, including diabetes, high cholesterol, dementia, memory loss, depression, and certain types of cancer. In contrast, the keto diet has earned low marks from experts due to its elimination of certain foods with essential nutrients and heavy emphasis on fat intake.

While both diets can promote weight loss, the Mediterranean diet is more sustainable and safer for long-term results. Its flexibility, health benefits, and ease of adherence make it a better option for those seeking gradual and lasting weight loss.

The keto diet is more restrictive and harder to stick to

The keto diet is much more restrictive than the Mediterranean diet and may be more difficult to follow. The ketogenic diet involves drastically slashing your carb intake to enter ketosis, a metabolic state in which your body uses fat for fuel instead of sugar. This typically means limiting carbs to 20-50 grams per day, which is a huge reduction and can be tough to maintain. As a result, the keto diet often eliminates many nutritious high-carb foods, including fruits, starchy vegetables, grains, and legumes.

In contrast, the Mediterranean diet is more flexible and less restrictive. While it recommends limiting certain foods, such as red meat, processed foods, and added sugars, no foods are technically excluded. This makes the Mediterranean diet easier to adhere to in the long run, as it is less restrictive and does not require strict macro tracking.

The keto diet can also be more challenging due to the need for diligent planning and the potential for negative side effects. As your body adjusts to burning fat instead of carbs, you may experience the "keto flu," which can include symptoms like headache, nausea, fatigue, dizziness, and brain fog. Additionally, some research suggests that food logging and restrictive diets like keto can foster an unhealthy relationship with food and contribute to disordered eating behaviours.

Furthermore, the keto diet may increase your risk of nutritional deficiencies. A study found that the keto diet provided less fiber, thiamin, vitamins B6, C, D, and E, and phosphorus compared to the Mediterranean diet. This is because the keto diet restricts many nutrient-dense foods, such as legumes, fruits, and whole grains.

Overall, the restrictive nature of the keto diet, combined with the need for careful planning and potential side effects, can make it harder to stick to compared to the more flexible and sustainable Mediterranean diet.

The keto diet may increase the risk of nutritional deficiencies

The ketogenic diet is a highly restrictive eating pattern that limits foods containing carbohydrates or sugar, such as fruits, starchy vegetables, grains, legumes, and sweets. This means that many nutrient-dense foods are excluded from the diet, which can lead to a higher risk of vitamin and mineral deficiencies.

A study published in the American Journal of Clinical Nutrition in 2022 found that the keto diet was associated with lower intake levels of several vitamins and minerals, including thiamine, vitamins B6, C, D, and E, and phosphorus. The keto diet was also found to be lower in fiber content.

Another study, published in Lancet Public Health in 2018, suggested that consuming too few carbohydrates in the long term could potentially shorten one's lifespan. The study found that eating less than 40% of calories from carbohydrates was associated with a higher risk of death within the next 25 years, especially when carbohydrates were replaced with animal fat or protein instead of plant-based sources.

The restrictive nature of the keto diet can also make it challenging for individuals to adhere to in the long term, which may further contribute to the risk of nutritional deficiencies.

It is important to carefully plan meals on the keto diet to ensure that nutrient needs are met and to minimise the risk of deficiencies. Consulting with a registered dietitian or nutrition professional can be helpful in ensuring that the diet is followed correctly and safely.

The Mediterranean diet is more plant-based and eco-friendly

The Mediterranean diet is considered more eco-friendly than the keto diet because it is much more plant-forward. It is also more sustainable and easier to stick to, as it is less restrictive and does not require eliminating entire food groups. The Mediterranean diet is also more affordable than keto, as it does not require the removal of staple foods like beans, lentils, and whole grains.

The Mediterranean diet has been praised by dietitians and doctors alike, and has been recognised as the healthiest overall diet by U.S. News & World Report for several years in a row. It has been proven to be healthy and easy to stick to because it is inclusive rather than restrictive. It has also been consistently ranked No. 1 in the U.S. News Best Diets rankings for healthy eating, whereas keto has earned low marks from health and nutrition experts.

The Mediterranean diet is a safe and effective option for weight loss and has been linked to a reduced risk of developing chronic diseases, including cardiovascular disease, type 2 diabetes, kidney disease, lung disease, cancer, Alzheimer's, and Parkinson's disease. It has also been associated with improved heart health, better blood sugar management, and enhanced brain function.

The keto diet may have negative effects on mental health

Firstly, restrictive diets like keto can contribute to disordered eating behaviours and a negative relationship with food. Individuals may become overly fixated on food, ignore feelings of hunger and satiety, and develop an unhealthy obsession with "eating right". This can lead to feelings of guilt and shame if "perfect" adherence to the diet is not achieved. Such behaviours can be indicative of a disordered relationship with food or an eating disorder, which can affect anyone, regardless of their background or identity.

Secondly, the keto diet can be challenging to adhere to due to its restrictive nature. It requires diligent planning and tracking of carbohydrate intake, which can be stressful and time-consuming. The potential for "cheating" or deviating from the diet may cause additional stress and anxiety. Social situations involving food, such as dining out or celebrating with cake, can become sources of worry and unhappiness.

Additionally, the initial side effects of the keto diet, often referred to as the "keto flu", can include headache, nausea, fatigue, dizziness, and brain fog. These symptoms can impact an individual's ability to work, socialise, and perform daily tasks, potentially leading to increased stress, anxiety, and depression.

Furthermore, the keto diet may increase the risk of vitamin and mineral deficiencies, which can have negative consequences for mental health. For example, deficiencies in B vitamins and vitamin D have been linked to depression and anxiety. The exclusion of whole grains, fruits, and legumes in the keto diet may also impact the gut-brain connection, as these foods are rich in fibre and prebiotics that support a healthy gut microbiome.

Finally, the keto diet's restriction of carbohydrate-rich foods may impact the production of serotonin, a neurotransmitter involved in regulating mood, appetite, and sleep. While the body can produce serotonin from the amino acid tryptophan, which is found in some high-protein keto-friendly foods, the process is less efficient than direct serotonin production from carbohydrates.

It is important to note that the potential negative effects of the keto diet on mental health may be mitigated by working with a qualified healthcare professional, such as a registered dietitian, to ensure the diet is safely and effectively implemented. Additionally, prioritising mental health and seeking support from a mental health professional if needed is crucial when considering any restrictive diet.

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