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The beginner's guide to the keto diet

Purition Strawberry keto yoghurt bowl.

The keto diet seems to be a phrase on everyone’s lips at the moment. Here at Purition, we’re clued up on what the keto diet involves and how it works.

This is because we’re keen to provide a product that can be enjoyed by everybody, including those who are following a keto diet. We’re also keen to dispel any myths about the keto diet, as it isn’t as restrictive as some may think.

Let’s take things back a step, though – before you decide that keto is for you, you’ll probably be asking yourself, what is keto? Today, we’ll go through everything you need to know about the keto diet, so you can work out if it’s something that might work for you.

What is the keto diet?

A keto or ketogenic diet is a low-carb, high-fat diet that uses stored body fat for energy instead. It has many benefits for weight loss, health and performance, as shown in over 50 studies. That’s why it’s recommended by a growing number of doctors.

Done right, the keto diet leads to our body entering the state of ketosis. This is a completely natural function that happens every night while you sleep. Ketosis is a metabolic state in which your body uses fat and ketones rather than glucose (sugar/carbohydrates) as its main fuel source.

Ketosis is a state at which the body has an extremely high fat-burning rate. Even the brain runs on fat, via ketone bodies. These are energy molecules in the blood (like blood sugar) which become fuel for our brains after being converted from fat by the liver.

How keto works...

  • Glucose is stored in your liver and released as needed for energy. However, after carb intake has been extremely low for one to two days following the keto diet, these glucose stores become depleted.
  • Your liver can make some glucose from the protein you eat via a process known as gluconeogenesis, but it cannot make nearly enough to meet the needs of your brain, which requires a constant fuel supply.
  • Ketosis can provide you with an alternative source of energy. Ketones, or ketone bodies, are made by your liver from fat that you eat and body fat. 
  • On a low-carb high-fat diet (LCHF) glucose and insulin levels decrease (through the lack of sugar and carbohydrates being consumed), so the liver increases the production of ketones in order to provide energy, you are then considered to be in nutritional ketosis.


To encourage ketone production, the amount of insulin in your bloodstream must be low. The lower your insulin, the higher your ketone production.

And when you have a well-controlled, sufficiently large amount of ketones in your blood, it’s basically proof that your insulin is very low and therefore, that you’re enjoying the maximum effect of your low-carbohydrate diet. 

Can keto be effective?

Let’s compare keto to fasting for a moment. Although both fasting and a keto diet will allow you to achieve ketosis, only a keto diet is sustainable over long periods of time. In fact, it appears to be a healthy way to eat that people can potentially follow indefinitely.

A low-carb diet lowers your levels of the fat-storing hormone insulin, allowing your fat deposits to be used for energy production. When your body is using fat from food you consume and your body fat for energy, you tend to want to eat less calories than you expend. This results in losing weight without hunger. 

Is keto bad?

Keto receives a fair amount of bad press from those who may not be nutritionally clued up on all the facts. People may see consuming less carbs as a dangerous thing. 

In the western world, it is deemed perfectly normal to consume a beef burger with fries and coke, but if you ask for the beef burger without the bun and salad instead of fries, and water instead of coke, you are suddenly somehow following a dangerous or unhealthy diet. 

However, a ketogenic diet doesn’t mean you miss out on important food with high nutritional value. You are simply replacing high carb foods with little / no nutritional value other than calories, for low carb foods that contain lots of healthy fats. 

Forexample, on the keto diet, you would turn the high carb meal into a keto meal with less overall calories and more nutrition by skipping the bread bun and having a salad. 

What can you eat on the keto diet?

There are loads of keto friendly foods, including:

  • Fresh vegetables
  • Low sugar fruit (berries)
  • Good quality meat
  • Fish & seafood
  • Eggs
  • Plain yoghurt
  • Dark chocolate

Can you drink milk on keto?

Reports suggest that dairy milk isn’t the best addition to a keto diet as milk contains lactose, which contains carbohydrates. Some recommend that unsweetened almond milk and coconut are good choices. 

Can you drink alcohol on keto?

Regular drinking is a high contributor to weight gain over time as most alcoholic drinks are high in sugar and carbs, especially beer. It might be best to steer clear of alcohol to see the best results from your keto diet.

However, your diet is what you make of it! If the keto diet and low alcohol consumption fits into your lifestyle, then great.

Which foods are high in fat?

You’ll be pleased to know that there are plenty of great options for your diet that include high levels of healthy fats that help you with your keto diet. These include:

  • Eggs
  • Avocado
  • Oily fish (salmon, tuna, mackerel, sardines, etc)
  • Cheese
  • Good quality meat and poultry
  • Full fat yoghurt
  • Whole milk
  • Butter
  •  Seeds & nuts (as found in abundance in Purition)

Is keto worth it?

You can guarantee noticeable results quickly with keto, but only if you stick with it. The good news is that proponents of the diet claim:

  • Increased energy levels
  • Improved mental alertness 
  • Generally fewer ailments

So, sticking with it has some serious upside. You can say goodbye to hunger on a keto diet because the body has access to lots of energy (body fat).

You will be less hungry, which is why many on the keto diet also incorporate fasting. Getting up in the morning for a carb fix is something the body does not do anymore, meaning, you can wake up and go without breakfast without worrying about the next carb fix. 

But remember, returning to eating as you did before, like with any other dietary change, will see weight gain return. If you have steadily been gaining weight for years, any temporary change you make is only ever going to have temporary results. If you return to eating the same way as before, the results (gradual weight gain) will still be the same. 

Is keto effective for other health concerns?

There have been reports made that the keto diet has eased diabetes symptoms and may improve blood glucose levels while reducing the need for insulin.

Similarly, some have reported that the keto diet has aided symptoms of arthritis, with reduced joint pain. However, there have been limited scientific studies into this, so it is always worth consulting with a medical professional if you are unsure about the keto diet working for you.

Regarding the keto diet relieving symptoms of IBS, there has similarly been limited study on this, however, a small amount of research conducted found that the keto diet provided some relief of symptoms of IBS. You can find out more about this specific study here. 

Who should not do a ketogenic diet?

For most people, the ketogenic appears to be very safe, although there are plenty of myths which suggest otherwise. However there are three groups of people who will require special consideration before following the keto diet:

  • Those who take medication for diabetes
  • Those who take medication for high blood pressure
  • Those who are breastfeeding 

Despite the many proven benefits of the ketogenic diet, it still is seen as controversial to some. The potential danger does regard certain medications, including those listed above. You should discuss changes in medication and lifestyle changes with your doctor if you are in any way concerned. They can advise you on the best way forward. 

Exercise on the keto diet

It’s worth noting that during the first few weeks, when you’re switching from a carb-rich diet to the opposite, your overall exercise game might decrease. 

This is brought on by the low carb flu as your body adjusts, and will likely pass within a few weeks. There are benefits of a high fat diet and high endurance sports, and similar benefits have been seen with powerlifting and weightlifting. 

For non-endurance sports, though, then you might find you need a greater carb intake. If this sounds like you, just take in more carbs on a day when you need to be at your best.  

Purition for the keto diet

Graphic of a drinking glass with the whole food ingredients listed inside.

Unlike meal replacement shakes that are full of flavourings and junk food, Purition is made of real food. With a high protein serving in every portion, our products are made of whole grains, seeds, nuts... and that’s it. 

We believe in making delicious products using the freshest ingredients. We know there’s a big difference between flavour and flavourings – and that’s what makes us different. 

Purition is low in carbohydrates, low in sugar and compatible with a keto diet. It contains just the right amount of protein, as well as around 6g fibre to aid and slow digestion and 12g wholefood fats, with no synthetic ingredients whatsoever.

Purition and ketosis

Purition can be a great addition to your diet when your body is in ketosis, as it is similar to fasting.

Both work by extending time the body uses fat instead of food. Similar to how you may enjoy Purition on a fasting diet as a delicious breakfast smoothie or small meal, so too can you enjoy Purition on a keto diet. 

You are getting a great supply of protein, will feel full after a tasty meal, but you aren’t consuming lots of carbs. Here at Purition, we know a thing or two about how keto works and how you can enjoy Purition products without being restricted. 

Find out more about using Purition support a keto diet.


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