How to get over the 'keto flu'
By The Low Carb Clinic, 7 May 2019 - 716 words (3.5 minutes)
Are you feeling fatigued, irritable or having trouble concentrating since you started a low-carbohydrate diet? Never fear, it’s probably just 'keto flu'!
‘Keto-flu’ can occur in the first couple of weeks of a low-carbohydrate diet, while your body switches from burning carbohydrates for fuel, to burning fat – so the good news is, it means you’re on the right track! Here are some simple, effective ways to help – so before you know it, you’ll have more energy and brain power than before...
During the first week of a low-carbohydrate diet, your body goes through lots of changes. Because carbohydrates tend to hold on to more water than protein or fat, the body loses extra water – and with that water, some minerals – including sodium and potassium. Lowered levels of insulin also promote these mineral losses, and together these factors can cause keto flu.
In addition, it takes on average 5-6 days for our bodies to start burning fat for fuel. So, when we stop eating carbohydrates, we can sometimes have a “slump” in energy at about day 3-5, as the last of the carbs are running out – until the fat burning machinery kicks into action. Then the energy starts to really ramps up! That’s why the carb craving can be quite intense in the first few days – and why it’s really important to not give in! High levels of sustained energy are just around the corner.
Symptoms of keto flu tend to be worst around day 3-5, but can go on for a couple of weeks, depending on what you are eating. Symptoms of keto flu may include fatigue, nausea, muscle cramps, difficulty concentrating, and cravings, dizziness, and headaches – so if you get keto flu, it’s easy to think about quitting! But be reassured this stage will soon pass, and you’ll be on your way to improved energy and overall wellbeing. Here are some tips to get you through:
Get enough water. For every 1 gram of carbohydrate stored in the body (as glycogen), we retain about 3 grams of water, so a low-carbohydrate diet can mean we lose excess water.
Get enough salt. Insulin encourages the body to retain sodium. So, when we lower insulin through a low-carbohydrate diet, we can also lose salt. Plus, salt and water tend to travel together.
Get enough potassium. The increased water and salt losses also cause the loss of potassium. Furthermore, lots of dietary sources of potassium (like beans, potatoes, and bananas) aren’t eaten on a low-carbohydrate diet.
So, if you’re getting symptoms of keto flu, try:
Adding more salt to food
Having a glass of water with half a tea spoon of salt – especially before exercising
Increasing potassium-rich, low-carbohydrate foods (like avocados, spinach, cream, steak, salmon or broccoli)
Enjoying foods naturally high in salt (like bacon, organ meats, bone broth)
Another important tip is to make sure you are eating enough fat!
When your body transitions from burning glucose to burning fat, changes occur in the mitochondria of your cells – which are the power-plants of your cells that produce energy for your body.
Give your mitochondria a consistent message by maintaining healthy levels of fat in your diet – if you keep switching back and forth from low-carb to high-carb, they’re going to get very confused, inefficient and burnt out.
When the body burns fat for fuel, the liver produces ketones as a by-product. The body can begin using the ketones quite quickly, but full keto-adaptation may take up to 12 weeks (or more). Being keto-adapted takes time because it results in mitochondrial biogenesis – that is, growth of more mitochondria  (meaning more power-plants), and a greater ability to burn fat for fuel.
Ketones are a cleaner, more efficient source of energy than carbohydrates. Burning ketones results in fewer free radicals and less oxidative stress in the body,   and a greater amount of ATP (energy).
Remember that a low-carbohydrate diet is not about cutting calories or starving your body: it is about eating nutrient-dense, low-carbohydrate whole foods to promote overall health. With a few little tweaks, it should be easy to overcome keto flu, and start enjoying the health benefits of a ketogenic diet.
Nourish yourself and fight the keto flu!
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