What is the keto diet?

The ketogenic diet has increased in popularity over the years. The keto diet is an extremely low-carb, high-fat diet that is meant to help you to lose weight and improve your overall health. The diet is centred around reducing the number of carbohydrates you eat and replacing them with healthy fats, so that your body is ultimately more efficient at burning fat for energy.

Let’s talk science

The ketogenic diet works by kick-starting a process named ketogenesis. Our bodies are generally powered by glucose (your blood sugar), which is derived from carbohydrates. Most people typically intake carbohydrates from food such as bread, potatoes, and fruit.

When our blood sugar levels drop, we will faint. In some cases, if our blood sugar levels drastically decline to alarmingly low levels, we can even die. The body is only able to store enough glucose to last a few days, meaning that if we didn’t intake carbohydrates for that time period, we’d quickly have to find another way to keep our bodies going.

Enter: ketogenesis.

Ketogenesis occurs when our livers break down fat into ketone bodies, which are usable energy sources. These ketone bodies, commonly referred to as ketones, can replace glucose to power the body. When these ketone levels are consistently raised, your body is in a state of ‘ketosis’, meaning it will burn up stored fats.

Ketosis can be achieved in various ways, such as by fasting, but the ketogenic diet focusses on eating generally less than 20 grams of carbohydrates a day to reach this state.

The diet

Various keto diets have differing macronutrient ratios:

  • Standard ketogenic diet: 75% fat, 15-20% protein, and 5-10% carbs
    This diet is the most commonly used, as it is extremely low in carbohydrates and high in fats, allowing you to kick start.
  • Targeted ketogenic diet: 65-70% fat, 20% protein, and 10-5% carbs
    This diet is often used by athletes and frequent gym-goers, as it enables you to add in more carbohydrates around workouts.
  • Cyclical ketogenic diet: 75% fat, 15-20% protein, and 5-10% carbs on keto days; 25% fat, 25% protein, and 50% carbs on off days
    This diet allows you to cycle in and out of ketosis while enjoying more carbohydrates on weekends or special occasions.
  • High protein ketogenic diet: 60-65% fat, 30% protein, and 5-10% carbs
    This diet incorporates a high percentage of protein making it easier to inchoate into your everyday routine however it’s important to remember that protein can also be converted into carbohydrates in the body so it could be harder to reach ketosis.

Foods to avoid

Although there are different variations of the keto diet, the main principle remains the same: limit food that is high in carbs. Foods to avoid include:

  • Sugary foods including fizzy drinks, fruit juices, chocolate, and sweets
  • Starchy foods including bread, pasta, rice, and cereals
  • Root vegetables including potatoes, carrots, and parsnips
  • Fruit including bananas, pineapples, and mangoes
  • Low-fat and diet foods as these are high processes and generally high in carbohydrates, instead, healthy fats should be consumed
  • Alcohol as most alcoholic drinks are high in carbohydrates

Foods to enjoy

The majority of your meals should be based on healthy fats and protein. Good foods to incorporate into your meal plan include:

  • Meat including steak, ham, sausage, bacon, and chicken
  • Fatty fish like salmon, tuna, and mackerel
  • Eggs that are free range and cooked in healthy oils if you want them fried
  • Butter and cream should be full fat
  • Unprocessed cheese, such as cheddar or goats cheese
  • Vegetables which are low carbs such as onions, peppers, spinach, and broccoli
  • Healthy oils like extra virgin olive oil or coconut oil

Avocados are also a staple in this diet as they can be used in many ways to inject some healthy fats into your meal.

Sample meal plan

Here is what your meals could potentially look like over three days!

Day one

  • Breakfast: 1 slice of bacon, 1 poached egg, 1 grilled tomato
  • Lunch: Chicken salad with olive oil and feta cheese
  • Tea: 1 pork chop (keeping the fat on) and cream cheese mashed with broccoli  

Day two

  • Breakfast: Omelette with avocado, peppers, and onions
  • Lunch: Keto protein chocolate milkshake
  • Tea: Salmon topped with butter alongside ‘riced’ cauliflower and sautéed kale

Day three

  • Breakfast: Ground flaxseeds combined with cream, water, and cinnamon
  • Lunch: Bacon, spinach, and blue cheese salad
  • Tea: 1 burger topped with avocado, wrapped in a large romaine leaf

Does it work?

Ketones have been shown to aid weight loss and help to improve insulin sensitivity. For this reason, many people dealing with prediabetes and diabetes find the diet helps them to maintain a healthier lifestyle and manage their symptoms. The diet has also been associated with helping to decrease blood pressure levels in people that are overweight or have type 2 diabetes.

The ketogenic diet can help you to lose weight whilst feeling full and avoiding calorie counting. It can be easy to slot into your everyday routine, as you can simply swap your carbohydrates for a ketogenic alternative. For example, you can replace burger buns with lettuce or mashed potatoes with mashed broccoli.

There is some caution to heed before implementing this diet into your daily routine. Some people report experiencing a ‘keto flu’ when first trying the diet. As your body runs out of glucose to produce energy and begins to rely on fats instead, this can make you tired and bring about some gastrointestinal issues.

There has also been some discussion about its long-term effectiveness. Many people regain weight after returning to carbs and find that their weight is not distributed in the same proportions when it does return. It's also possible to lose muscle mass, as you’ll typically be eating more fat than protein.

Closing thoughts

Overall, the ketogenic diet can be a good method for jump-starting your healthy routine and losing some weight, particularly if you are concerned about managing prediabetes or diabetes. However, it is important to remember the downsides and counteract these effects. You should always consult a doctor before implementing a new diet, especially if you have diabetes or any other illness that can be affected by your diet.