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 is fast becoming a favourite when it comes to weight loss, but what does it entail? From what it is, to foods you can eat on the ketogenic diet and vegetarian Keto diet ideas, we’ve got it covered.

    The Ketogenic diet – also known as the keto diet or the ketosis diet as it’s commonly called – is proving very popular among celebrities and everyday folks alike. Everyone from the Kardashians to sports stars like Lebron James have weighed in with their support of the diet, saying it’s helped them to shed the pounds and lose substantial amounts of weight.

    It’s also known simply as a low-carb diet, as most ketogenic diets involve eating less than 35 grams of carbohydrates a day. Doing this is believed to completely reverse how your body functions and change how the dieter views nutrition.

    MORE: How did Gregg Wallace lose weight? This is the MasterChef star’s diet plan

    Like many diets though, there are some critics that feel the diet is just another way to lose weight quickly, rather than a long-term weight loss plan that helps you drop weight in a healthy way. Other diet plans that have been promoted alongside the keto diet however, include high-protein and high-fibre diets which are similar to the keto diet as they require more or less of some nutrients.

    We’ve spoken to experts Dr Shan Hussain and Dr Sohere Roked to find out everything you need to know about the trendy diet…

    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.

    On keto, 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, which 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.

    The Keto diet: everything you need to know about ketogenic diet plan

    Foods to eat on the keto diet?

    The most important thing for reaching ketosis is to avoid eating too many carbs – 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.

    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?

    Many celebrities, including Kim Kardashian, Megan Fox and Adriana Lima, have raved about the benefits of the keto, or a low-carb, diet.

    Halle Berry has credited it with managing her diabetes, which she has had since she was 19-years-old.

    She previously wrote on Instagram, ‘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.’

    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.

    The Keto diet: everything you need to know about ketogenic diet plan

    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.

    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 Keto diet: everything you need to know about ketogenic diet plan

    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.

    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, Dr Shan Hussain, GP and Health & Wellness Advisor, confirmed 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.