28th February, 20203 min read

What is the ketogenic diet?

Medical reviewer:
Healthily's medical team
Healthily's medical team
Tomas Duffin
Tomas Duffin
Last reviewed: 28/02/2020
Medically reviewed

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The ketogenic (or ‘keto’) diet was first developed over 100 years ago as a treatment for epilepsy.

Starving yourself for a short period of time was thought to reduce seizures because when you don’t eat, the body produces substances, called ketone bodies, which can help to correct abnormal nerve signals that may cause epilepsy.

But how the diet is used has evolved over time, and it’s now popular among those who want to burn fat.

When it comes to weight loss diets, low-carbohydrate and high-protein eating plans tend to dominate. But the keto diet is a little different - followers have to stick to low-carbohydrate and high-fat meals.

The diet has no shortage of celebrity fans, but a debate about its potential risks and benefits continues.

So is this diet safe, and is it right for you?

Weight loss benefits of the keto diet

Even though the keto diet is a popular way to lose weight, research into how well it works is lacking. A 2004 critical review of previous studies found some evidence that following a high-protein diet may be more effective for weight loss than a low-fat diet.

But this doesn’t mean that the high-fat keto diet is an effective way to lose weight, especially in the long term.

Keto diet foods

Health benefits of the keto diet

It’s sometimes said that the keto diet can improve conditions like heart disease, Parkinson’s disease, Alzheimer’s disease and even cancer, but there’s little scientific evidence to support these claims.

What has been more closely studied is the idea that the keto diet can help people with epilepsy that doesn’t respond to medication.

Findings from an 11-study review, published in the Cochrane Database of Systematic Reviews in 2003, suggest that the diet may reduce seizures and other symptoms of epilepsy. However, as these studies were fairly small in size (66 adults and 778 participants in total), the results can’t be taken as conclusive proof that the keto diet improves epilepsy symptoms.

Risks of the keto diet

The keto diet is a high-fat and low-carbohydrate diet. This means that a typical day on the diet involves increasing your fat intake and severely limiting how many starchy carbohydrates you eat.

Some fat is good for you, but eating too much saturated fat can raise your cholesterol levels and increase your risk of heart disease.

A 2019 scientific review, published in the journal Nutrients, also highlighted that as the keto diet involves cutting out lots of foods, it may put some elderly people at risk of not getting all the nutrients they need.

Saturated fat butter

Is the keto diet right for me?

The keto diet has its risks and benefits, and as there’s no one-size-fits-all diet, it’s difficult to conclusively say who should or shouldn’t follow the ketogenic style of eating.

It’s worth bearing in mind that the keto diet requires a lot of commitment and you’ll need to restrict what you eat.

If you’re interested in the keto diet and would like more guidance on it, see a dietitian for advice.

Alternatively, if you’d like to know more about how to lose weight safely, read this article on how to diet.

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