Keto diets
What is a keto diet?
Keto is the more common term for ‘ketogenic’. The keto diet was originally developed in 1924 as a treatment for epilepsy. For children with epilepsy who have continued to experience seizures while taking antiepileptic medications, a supervised ketogenic diet has been useful in controlling seizures.1However, the diet has become very popular over the past few years and many people now use it as a way to shed weight quickly.
Here we examine what the keto diet is, how it works and whether it’s the best approach for weight loss.
How does keto work?
Glucose (a type of sugar) is the body’s preferred source of energy. However, the keto diet aims to use fat as the body’s primary fuel source, rather than glucose. A keto diet requires you to limit carbohydrates (which the body breaks down into glucose) and replace them with foods high in fat. This sends your body into a state called ketosis.
When this happens, your liver uses fat to produce ketone bodies (or ketones). These ketones replace glucose as the primary source of energy which means the body uses its own fat stores to fuel itself. Using your fat stores as a source of energy is what leads to weight loss.
While a keto diet sounds easy, getting the body to make ketones and enter a state of ketosis can be difficult. It requires a significant reduction in carbohydrates and it can take several days for the body to enter ketosis. Eating too much protein, however, can interfere with this process.2
What can you eat on a keto diet?
The keto diet focuses on eating high levels of fat, moderate amounts of protein and very few carbohydrates. The usual ratios from total daily calories are:
70-80% fat
10-20% protein
5-10% carbohydrate
The keto diet limits carbohydrate intake to just 20-50g per day. For context, a single slice of bread contains 15g of carbohydrates, so you can see that the diet is very low on carbs!
Typical foods that are allowed on the diet include:
Fats— coconut oil, flaxseed oil, olive oil, macadamia oil, oil-based salad dressings, high-fat dairy products such as cheese, butter, cream and animal fats such as lard, tallow, etc.
Proteins— beef, lamb, poultry, pork, fish, seafood, eggs and tofu (these don’t have to be lean)
Vegetables— spinach, rocket, kale, broccoli, mushrooms, celery, cabbage
Fruits— avocado, raspberries, blackberries, strawberries, lemons and limes
Nuts and seeds— macadamias, walnuts, almonds, sunflower seeds, flax seeds and nut butters
Drinks— tea, coffee, water, almond milk
Sweeteners— low-carb sweeteners
Herbs and spices
Can you lose weight on a keto diet?
A keto diet often leads to quick weight loss. There are several reasons for this.
The initial weight lost on a keto diet is often water. That’s because our body holds onto 3-4 grams of water for every gram of carbohydrate we eat. Dramatically cutting our carbohydrates automatically translates into water-weight lost on the scales.
Secondly, because there are fewer foods ‘allowed’ on this diet, followers of the plan often end up eating less food. This drop in calories will automatically result in weight loss. Another theory to account for weight loss is that high levels of fat and protein leave you feeling fuller for longer, so you are less hungry and therefore eat less food.
Studies show that in the short-term (2-6 months), a very low carbohydrate diet can help you lose more weight than the standard high-carb, low-fat diet. However, by the 12-month mark, total weight loss between the two approaches is fairly similar.
While a keto diet may lead to rapid weight loss initially, studies show that its restrictive nature makes it hard for people to follow long-term. This means people start the diet, and then stop which contributes to unhealthy ‘yo-yo’ dieting and weight cycling (i.e. losing weight and regaining it over and over). Long-term, this can cause problems such as further weight gain, higher body fat percentage, muscle loss, and an increased risk for diabetes, heart disease and blood pressure:
Is a keto diet safe?
Unfortunately, the keto diet isn’t without its risks. Key problems with the keto diet include an increased risk for:
Heart disease — Keto diets have been associated with an increase in ‘LDL’ cholesterol levels (the bad cholesterol) which is linked to heart disease.
Liver problems — Metabolising high levels of fat can place a strain on the liver and make any pre-existing conditions worse.
Kidney problems — Our kidneys play a role in metabolising protein, however high levels of protein recommended on the keto diet can overload our kidneys and lead to the formation of kidney stones.
Nutrient deficiencies — It’s not possible to eat a wide variety of fruits, vegetables and grains on the keto diet plan which can lead to nutrient deficiencies.
Constipation — Cutting out fibre can lead to constipation and increase the risk of bowel cancer.
While a keto diet might sound like it’s fast and effective for weight loss, there may also be some unpleasant side effects. These include:10
fatigue
dehydration
headache and dizziness
bad breath
nausea
poor sleep
It’s important to understand that keto diets do not align with the Australian Dietary Guidelines which recommend eating lots of fruits, vegetables, whole grains and plant-based proteins.
What should I do if I want to lose weight
The key to losing weight and maintaining that loss is to follow a plan that you can sustain over time. Experts recommend the best way to lose weight is to avoid fad diets and to11:
be physically active most days
eat a healthy, balanced diet that includes:- different coloured fruits and vegetables- whole grains- lean meats, poultry, fish, eggs, tofu, nuts and seeds- legumes/beans- low-fat milk, yoghurt and cheese
make water your drink of choice
reduce intake of saturated fats, added sugars and salt
reduce intake of alcohol
When should you see a doctor?
If you want to lose weight you should visit your doctor before changing your lifestyle or following a particular diet, especially if you have a pre-existing condition or are taking prescription medication.
Your doctor knows your medical history and can provide advice on the best weight loss approach for you.
Your local MediADVICE Pharmacist is available to help you manage your health and help you achieve and maintain a healthy weight. Speak to your MediADVICE Pharmacist about your weight loss journey so we can recommend products and medications that may be suitable for you, or refer you to a doctor if necessary.
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