ccording to the World Health Organisation report of 2020, 58.1 percent of people in Pakistan are overweight, and 43.9 percent of the population is suffering from obesity. Obesity is a risk factor for developing diabetes, hypertension and cardiovascular diseases.

Many diet plans have been used to reduce weight in earlier decades. A majority of them focused on low-carb intake but kept protein in moderate to high amounts. The ketogenic diet, on the other hand, not only focuses on cutting down on carbs but also recommends reducing proteins, as amino acids in proteins also lead to glucose formation and prevent ketosis.

Russel Wilder first used the ketogenic diet to treat epilepsy in 1921. He also coined the term “ketogenic diet.” The ketogenic diet has also been tested and used in closely monitored settings for cancer, diabetes, polycystic ovary syndrome and Alzheimer’s disease.

Ketogenic diet primarily consists of high fats, moderate proteins and very low carbohydrates. Ketogenic resources suggest an average of 70-80 percent fat from total daily calories, 5-10 percent carbohydrate, and 10-20 percent protein. This diet restricts carbohydrates to <50 grams/day (or < 200 kcals/day since each gram of carbohydrate provides four kcals of energy). The Harvard School of Public Health suggests that for a 2,000-calorie diet, this refers to about 165 grams fat, 40 grams carbohydrate and 75 grams of protein.

Carbohydrates are the primary source of energy production in body tissues. When the body is deprived of carbohydrates due to reduced intake to less than 50g per day, insulin secretion is significantly reduced and the body enters a catabolic state. Glycogen stores deplete, forcing the body to go through certain metabolic changes. Two metabolic processes come into action when there is low carbohydrate availability in body tissues: gluconeogenesis and ketogenesis – the increased breakdown of fats that result in fatty acids which are metabolised to ketones. As long as the body is deprived of carbohydrates the metabolism remains in the ketotic state. The nutritional ketosis state is considered quite safe, as ketone bodies are produced in small concentrations without any alterations in blood pH. The ketone bodies so synthesised can be easily utilised for energy production by the heart, muscle tissue and kidneys. The ketone bodies can also cross the blood-brain barrier to provide an alternative source of energy to the brain. Ketone bodies produce more energy in comparison to glucose, sometimes rightly called a “super fuel“. This allows the body to maintain efficient fuel production even during a caloric deficit. Hence, people on a ketogenic diet initially experience rapid weight loss – up to 10 lbs in two weeks or less.

So what to eat? Cocoa butter, poultry fat and most plant fats (olive, palm, coconut oil) are allowed, as well as foods high in fat, such as avocado, coconut meat, certain nuts (walnuts, almonds), and seeds (sunflower, pumpkin, sesame, hemp, flax). Although dairy can be a significant source of fat, some are high in natural lactose sugar such as cream, ice cream and full-fat milk, so they are restricted. However, butter and hard cheeses may be allowed because of the lower lactose content. Moderate protein sources include fish, organ meat and poultry. Most non-starchy vegetables are included: leafy greens (kale, spinach, lettuces), cauliflower, broccoli, Brussels sprouts, asparagus, bell peppers, onions, garlic, mushrooms and cucumber. Certain fruits in small portions, like berries. Despite containing carbohydrates, they are lower in “net carbs” than other fruits. Net carbs or impact carbs are the amount of carbohydrate that are directly absorbed by the body and contribute calories. Dark chocolate (90 percent or higher cocoa solids), cocoa powder, unsweetened coffee and tea, unsweetened vinegars and mustards, herbs and spices can be used.

You can try food recipes out of cauliflower rice and scrambled eggs. Almond flour can be used to make pizza. Pancakes can be made using coconut/ almond flour along with vanilla extract and sugar replacement (vegan sweeteners like stevia). Whole grains, cereals, legumes, beans and refined sugars have to be avoided.

Is ketogenic diet safe?

The most common and relatively minor short-term side effects of the ketogenic diet include a collection of symptoms like nausea, vomiting, headache, low mood, dizziness and brain “fog”, fatigue, insomnia, low mood, irritability and constipation, sometimes referred to as keto flu. These symptoms resolve in a few days to a few weeks. Ensuring adequate fluid and electrolyte intake can help counter some of these symptoms. Long-term adverse effects include hepatic steatosis, hypoproteinemia, kidney stones, osteoporosis, increased levels of uric acid in blood and vitamin and mineral deficiencies. It is important to not solely focus on eating high-fat foods but to include a daily variety of the allowed meats, fish, vegetables, fruits, nuts and seeds to ensure adequate intakes of fibre, B vitamins, and minerals (iron, magnesium, zinc) — nutrients typically found in foods like whole grains that are restricted from the diet. Because whole food groups are excluded, assistance from a registered dietitian may be beneficial in creating a ketogenic diet that minimises nutrient deficiencies.

The ketogenic diet is contra-indicated in patients with pancreatitis, liver failure, disorders of fat metabolism and porphyrias.

Hence, this diet regimen that has proven to be very effective for rapid weight loss is a very-low-carbohydrate and high-fat ketogenic diet. A ketogenic diet may be followed for a minimum of two to three weeks up to six to twelve months. The transition from a ketogenic diet to a standard diet should be gradual and controlled. The short-term effects (up to two years) of the ketogenic diet are well-reported and established. However, the long-term health implications are not well known due to limited literature. A ketogenic diet improves health outcomes with respect to hypertension and diabetes. It also improves good cholesterol. However, increased use of saturated fats may lead to a rise in bad cholesterol (LDL), so one must be watchful of this. It’s better to include unsaturated fats (olive, nuts, seeds, fish) rather than saturated fats from animal resources (beef, poultry, dairy products).

The writer is a consultant in family medicine [MBBS, FCPS, MRCGP(int)]