Keto diet: what is the ketogenic diet and what can you eat on it?

Everything you need to know about the keto diet.
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  • The keto diet has been around for years but it undoubtedly remains one of the most popular, and well researched, weight loss plans out there. 

    It’s not one of the diets that work fast but rather a way to change eating habits and develop a healthier way of eating in the long term, fans of the diet claim. While some skeptics suggest it’s outdated for painting carbohydrates as non-essential and even representatives of Harvard Medical School have warned of its risks.

    The low-carb, high-fat plan is a favourite of celebrities and sports people alike though, with many citing the diet’s benefits. Much like the high protein plan or the high fibre diet, the Keto diet utilises the foods we eat every day as well. Halle Berry (who has type 2 diabetes) is famously a fan, along with the Kardashians and basketball player Lebron James.

    So while you’ve probably heard of the keto diet and similar ones, like the Paleo diet and the Atkins diet, you might be a little unsure of what it actually is.

    What is the keto diet?

    Essentially the keto diet is a low-carb, moderate-protein and very high-fat eating plan which puts the body into a metabolic state known as ketosis.

    This ‘state’ forces the body to burn fat rather than carbs for energy.

    Woman eating as part of the keto diet

    Credit: Getty

    On the keto diet, your insulin (the fat-storing hormone) levels drop, which allows your fat cells to travel to the liver and get converted into ketones (an alternative fuel for the body). This effectively turns your body into a fat-burning machine.

    The end goal of a properly maintained keto diet is to force your body into this metabolic state through starvation of carbohydrates instead of a starvation of calories.

    Foods to eat on the keto diet

    The most important thing for reaching ketosis is to avoid eating too many carbs and choose low carb recipes. The fewer carbs, the more effective results you’ll see.

    Foods you can eat on the ketogenic diet 

    • Meats – fish, beef, lamb, poultry, eggs, etc.
    • Leafy greens – spinach, kale, etc.
    • Above ground vegetables – broccoli, cauliflower, etc.
    • High fat dairy – hard cheeses, high fat cream, butter, etc.
    • Nuts and seeds – macadamias, walnuts, sunflower seeds, etc.
    • Avocado and berries – raspberries, blackberries, and other low glycemic impact berries.
    • Sweeteners – stevia, erythritol, monk fruit, and other low-carb sweeteners.
    • Other fats – coconut oil, high-fat salad dressing, saturated fats, etc.
    Person preparing avocado, part of the keto diet

    Credit: Getty

    Foods to avoid on the ketogenic diet

    • Grains – wheat, corn, rice, cereal, etc.
    • Sugar – honey, agave, maple syrup, etc.
    • Fruit – apples, bananas, oranges, etc.
    • Tubers – potato, yams, etc.
    • Legumes.

    Does the keto diet work?

    For many people, the keto diet is an effective way to lose weight and manage various health conditions.

    Multiple studies suggest that it helps with weight loss in two main ways: reducing hunger and promoting the loss of water weight.

    Firstly, the state of ketosis helps to decrease the body’s level of the hormone gherlin, otherwise known as ‘the hunger hormore’. Reducing this hormone in the body could cause people to eat less through the day and consume fewer calories as a result, potentially ending in weight loss.

    This is only suggested to be successful in the short term, however, and many trials on the subject tend to come up inconclusive.

    Walnuts and almonds, part of the keto diet

    Credit: Getty

    Secondly, the keto diet has been associated with a loss of water weight due to the substantial reduction in carbohydrates. Carbohydrates, when they’re stored in the body, hold water. So when you reduce the amount of carbs going into the body, including during the keto diet, these stored carbohydrates are released with the water, resulting in weight loss in some circumstances.

    Halle Berry is just one of the celebrities who has raved about the benefits of the keto diet.

    She said in an Instagram post, ‘Being diabetic most of my life, I have always had to take food very seriously. So for years, I have been following the keto or ketogenic diet. I hate the word “diet” so while you’ll see the word diet, just know I encourage you to think of it as a lifestyle change NOT A DIET! Keto is a very low-carb food plan which actually forces your body to burn fat like crazy.’

    She also credits the keto diet as ‘largely responsible for slowing down my ageing process,’ and helping her lose her ‘baby belly,’ control her appetite, and boost her energy and mental performance.

    What are the benefits of the keto diet?

    1. Weight Loss

    One of the main reasons people choose to undergo a diet is to lose weight. Because the ketogenic diet forces the body to use fat as an energy source, you’ll certainly see results if you stick to the plan.

    There are over 30 scientific studies showing that, compared to other diets, low-carb and keto diets result in more effective weight loss. Dr Sohere Roked, from OMNIYA MediClinic, adds that because you are removing carbs and sugars largely from your diet, fat is the body’s main source of energy and will burn that when it has no other option.

    2. Controlled blood sugar

    Dr Roked confirms that keto naturally lowers blood sugar levels –  you’re not eating as many carbs, so your body can’t produce glucose.

    woman running with headphones on path

    Credit: Getty

    3. Increased energy

    Because a keto diet helps your body turn fat into an energy source, it is also helping to increase your energy levels as it is giving your body a more reliable energy source.

    This allows you to feel more energised throughout the day.

    Better appetite control

    Fat is naturally more satisfying and ends up leaving us in a satiated (‘full’) state for longer. This means you should find yourself craving less junk food and snacking in-between meals less on the keto diet.

    Are there any side effects of the keto diet?

    The most common side effects for people undergoing the keto diet include headaches, tiredness, muscle fatigue, cramping and heart palpitations. These symptoms are mild and short-lived for most people as your body gets used to burning a new energy source, fat.

    Woman researching side effects of keto diet

    Credit: Getty

    You may experience cramps, specifically leg cramps, due to keto being a diuretic. Make sure to drink plenty of fluid and up your sodium intake – sprinkle a little salt on everything!

    You may also experience constipation, so again, make sure you are drinking enough water and ensure the vegetables you eat contain quality fibre.

    Dr Roked warns that there are concerns that the diet can cause cardiovascular disease or cause breakdown of muscles.

    If you are worried about undertaking the diet, or have not undergone drastic diet change before, it’s worth consulting your GP to make sure it’s safe for you to try.

    On a more positive note, Dr Roked sites that some early studies have shown that the ketogenic diet may help dementia as well as reduce autoimmune diseases such as autoimmune thyroid conditions.

    Who should not eat a ketogenic diet?

    While this diet is normally very safe, there are certain groups that need to take extra precautions when planning to embark on a keto diet.

    People who suffer from diabetes may have to dramatically lower any insulin doses they take immediately.

    As the keto diet restricts the carbohydrates that raise your blood sugar, you may no longer need medication to lower it, GP Dr Shan Hussain told to GoodtoKnow. Taking the same dose of insulin as you did prior to adopting a low-carb diet might result in hypoglycemia (low blood sugar).

    If you are on blood pressure medication and start a low-carb diet, there’s a risk of getting low blood pressure, which means you may very quickly become too healthy for your medication.

    Dr Shan advises anyone who is ‘on medication for diabetes or hypertension should proceed with caution and seek medical advice prior to undertaking the Keto diet’.

    If you feel weak, tired, dizzy or generally unwell you should check your blood pressure. If it’s low, e.g. below 120/80, you should contact your doctor to discuss lowering or stopping your medication.

    Women who are breastfeeding should also be cautious and choose a more moderate low-carb diet as in extremely rare cases a strict low-carb diet like keto could be potentially dangerous.

    Breastfeeding can cause you to lose sugar via the milk, possibly around 30 grams per day or more, so not eating carbohydrates in this situation can possibly lead to a dangerous condition called ketoacidosis, in rare cases.

    Try to stick to around 50 grams of carbs a day and always consult your health advisor or breastfeeding specialist for advice before embarking on a diet while breastfeeding.

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