Ketoses: what is it and how does it work?

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Posted by Linda O'Byrne (Atkins Nutritionist)

Atkins is a low carbohydrate lifestyle, as you probably know. Ketosis is an important part of a low carb regime. But what does that actually mean? How does the keto diet differ from the Atkins diet?

Do you want to get leaner, fitter and feel more energetic? Atkins can help by helping you burn more bodyfat, by way of ketosis.


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What is ketoses?

Ketosis is a metabolic process and occurs when you reduce your intake of carbohydrates.  Normally, carbohydrates are utilised by the body for energy. When you reduce carbohydrates, your body will look for another source of energy. This is when your body breaks down fat as a source of energy. This comes from the fat you eat, plus body fat. This process is called ketogenesis or ketosis. This typically occurs when carbs are reduced to 20g or less, per day, so similar to Phase one of Atkins.

This process is explained in the video below:

How do you get in ketosis?

In ketogenesis, fat becomes the most important source of energy. However, this process does not happen automatically:

You get into ketosis if you consume so little carbohydrates that your body starts getting energy from your fat reserves instead of the carbohydrate reserves. The moment at which this actually happens differs per person. Someone who does a lot of exercise can generally consume more carbohydrates to get into ketosis than someone who doesn't.

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How many carbohydrates can you eat per day to get / stay in ketosis?

In most cases, the limit is around 20 grams of carbohydrates per day. On average, this amount of carbohydrates forces your body to use your fat reserves as a source of energy. Note that this number varies per person. When you follow Atkins, you learn to discover where your personal carbohydrate balance lies. You can read more about this in the chapter What does a keto diet look like?

How long does it take to get into a ketogenic state?

This usually happens after three to four days. Because your body normally extracts energy from glucose, it searches for a new energy source. The body then breaks down fat to get energy. Ketones are produced when converting fat into energy. These ketones play an important role in the ketogenic diet.

Ketones are a type of acid that your body produces when fats are used as an energy source. There are three different types of ketones:

  • Beta-hydroxybutyric acid;
  • Acetoacetate;
  • Acetone.

These acids are created in your liver and, via your bloodstream, they then end up in the urine in your bladder after which you urinate them. Only acetone leaves the body through the breath.

In a normal situation, the concentration of ketones in your body is low and it never exceeds 0.3 mmol / l. When your body is in ketosis, the concentration of ketones increases and your body soon reaches the level of 1.5 mmol / l. This is the moment that your body converts the fats into energy. 

The image below shows a graphical representation of the ketosis process:


Why follow a ketogenic diet?

The most common reason for getting into ketosis is to lose weight. Because you use fats as an energy source in the keto diet, it is easier to burn body fat.  In addition, following a ketogenic diet usually means you feel less hungry as blood sugar levels stabilise when eating protein & fat containing foods, as well as vegetables. These two macronutrients give you a full feeling for longer.

Reducing carbohydrates also means that, after eating, you are less likely to experience a bloated feeling or an after-dinner dip. These are often consequences of a rapidly rising glucose level after a meal. Because these spikes in glucose levels will no longer occur, you should feel less bloated, have more energy and no cravings.

The decrease in glucose in the body can ultimately contribute to optimised cholesterol levels and lower blood pressure.

Benefits of ketosis at a glance:

  • Weight loss
  • Fat burning
  • No sugar cravings
  • Improvements in mood
  • Stabilised blood sugar levels
  • Better concentration
  • Lower triglycerides
  • Lower blood pressure
  • Cholesterol levels improved

What does a keto diet look like?

With a ketogenic diet , it is important that you reduce the number of carbohydrates in your diet to a level which will trigger ketosis. Therefore, we recommend starting with phase 1 of Atkins which recommends up to 20 grams of carbohydrates per day.

When fat burning has started, you gradually move on to phase 2 and phase 3. Until you finally reach your target weight. Then you go into ‘Lifetime Maintenance’ which is Phase 4. Here you have found your personal carbohydrate balance and you know how many carbohydrates you can eat to maintain your ideal weight.

During all 4 phases you mainly eat foods with lots of healthy fats and proteins. The carbohydrate-rich products are largely replaced by low- carbohydrate products with a high protein and fat content such as eggs, (fatty) fish, vegetables, meat and oils. As you get closer to your goal weight, you can add foods with a little more carbohydrates to your diet.

Read here everything about the 4 phases of Atkins and the associated (type of) products.

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How does the keto diet differ from Atkins?

During Atkins we guide you through your new lifestyle from start to finish. Part of this new lifestyle can be ketosis, but that depends on what your goal is.  In many ways, Atkins doesn’t differ much from the ketogenic diet, in both cases, proteins and fats are the main part of your diet.

But if weight loss isn’t your goal and you just want to feel just better, fitter and more energetic? Then ketosis does not have to be part of Atkins and we help you feel fitter and more energetic with the right food. Without losing weight.

What are the symptoms of ketosis?

Getting into ketosis is associated with certain symptoms in some people. The body needs some time to adjust to the new diet. That is why it is possible that fatigue and concentration problems may occur in the first few weeks. You can reduce the symptoms by drinking a cup of stock/broth. Eventually the symptoms will simply disappear after a short period, when the body is used to it.

If you eat enough vegetables and use a multivitamin, the diet remains nutritionally balanced.

Because the ketone acetone leaves the body through the breath, it is possible that you will suffer from bad breath in the first few weeks. This also decreases over time.

All symtoms at a glance

  • Bad breath
  • Letheless
  • Tired
  • Irritated
  • Less energy
  • Decreased condition
  • Slower recovery
  • Decreased libido
  • Digestive problemsfalling
  • Difficultyasleep
  • Longing for sugar (carbohydrates)

How to test if you're in ketosis?

You may not be able to recognise whether you are in ketosis, through physical symptoms physical differences. To ensure that you are in ketosis you can perform a test via a test strip. This test strip is available at the pharmacy. You have to pee over the strip. The strip discolors when the body is in ketosis.

But it is also likely that you will experience physical symptoms. Remember that the body must always adapt to such a rigorous change. Side effects / complaints often occur during that adjustment period.

So always realize that these side effects are temporary and a logical phenomenon.

Is the ketosis diet suitable for me?

Everyone can follow the keto diet. People who use insulin should preferably seek guidance from a specialized dietitian or doctor.

For athletes, this type of diet may not be so obvious in the first instance. Athletes are often set to eat a lot of carbohydrates. Yet it is precisely this group where a lot of experiments are being conducted with the ketogenic diet with surprisingly positive results. (source)