What’s the best weight-loss diet? From Keto Diet to 800 Diet - how plans compare, and are they healthy?

The New Year often sees people go on the hunt for a diet plan - but are they really the best way to lose weight?

<p>There are many weight loss diets on the internet - but can they be trusted? (image: Shutterstock)</p>

There are many weight loss diets on the internet - but can they be trusted? (image: Shutterstock)

The clean slate a New Year offers leads many people across the UK to consider their lifestyles.

According to a YouGov poll, a quarter of Brits make a New Year’s resolution every year.

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Improving fitness is the top goal, but it is closely followed by losing weight.

Tackling your waistline is not easy to achieve, and there can be a lot of misinformation out there on how best to go about it.

So, NationalWorld has sought out the advice of leading diet expert and spokesperson for the British Dietetic Association (BDA) Priya Tew to get her advice on weight loss dieting.

Here is her take on the leading diets - from the Keto Diet to the 800 Diet - as well as her top tips on the best way to shift unwanted pounds.

Many people attempt weight loss diets at the start of a new year (image: Shutterstock)

Keto Diet (and other low-carbohydrate diets)

The Ketogenic diet is a low-carb, high fat diet that aims to get the body to burn fat rather the carbohydrates for its energy

The Ketogenic diet is a diet that is used clinically for the treatment of epilepsy.

It was not designed to be used as a weight loss diet.

Whilst low-carb diets can be effective for helping with weight loss, this is not because carbohydrates are something we need to restrict or are a magic cure for weight loss.

It is down to an overall reduction in energy intake.

Getting more fruit and veg into your diet can be a good way of achieving weight loss (image: Shutterstock)

Vegan Diet

The Vegan Diet involves people ditching meat and other foods derived from animals. It is particularly popular at this time of year due to the Veganuary challenge

This is not a diet to follow specifically for weight loss, but a way of eating, or a lifestyle, that requires dedication and attention to nutrition.

There are nutrients such as: calcium, iron, zinc, iodine, selenium, vitamins B12 and omega-3 fatty acids that are harder to get on a vegan diet, so planning your food intake and having a good knowledge is key.

Choosing to eat more plants and adding diversity to your diet, while still eating some animal products, can also be a more manageable way of eating without going fully vegan.

The Mediterranean Diet is viewed as being very healthy, but it might not see you lose weight (image: Shutterstock)

Mediterranean Diet

The Mediterranean Diet follows the traditional healthy eating habits of people from countries bordering the Mediterranean Sea, like France and Spain. It’s high in vegetables, fruits, legumes, nuts, beans, cereals, grains, fish, and unsaturated fats such as olive oil

This is an evidence-based way of eating with proven health benefits for your heart and long term health.

It is not a weight loss diet, but if you increase your intake of fruit and vegetables, wholegrains and lean proteins, it is likely to lead to weight loss if your body needs to lose weight.

The Mediterranean Diet is a way of eating that is definitely good to follow.


The FODMAP Diet is one that is low in carbohydrates that ferment in the digestive system. These can be found in products like soft fruits and dairy. It stands for Fermentable Oligo-, Di-, Mono-saccharides And Polyols

The low-FODMAP diet is another evidence-based diet that is used in the treatment of irritable bowel syndrome (IBS).

It is not designed for weight loss and should not be used as a way to lose weight!

Instead, it is a way of working out if there are any foods that upset your digestive system by eliminating them and then later reintroducing them to your diet.

It is a complex diet that should be followed with dietetic support.

(Priya Tew is the author of a book on this subject which is available from the Waterstones website)

Meal replacement diets often involve consuming calorie controlled shakes (image: Shutterstock)

The Cambridge Diet (and other meal replacement diets)

The Cambridge Diet is an example of a meal replacement diet, where participants consume particular foods or shakes with a particular onus on calorie control

Meal replacement diets are sometimes used by dietitians to help people lose weight.

But these are used in a structured way, with education and support to help the person to move back to eating a normal diet.

The problem with doing these diets on your own can be that you do not get education and support.

So, whilst you may lose the weight quickly, the weight does not stay off in the long term.

800 diet (and other fasting diets)

The 800 Diet is an example of a fasting diet, where people restrict their calorie intake on certain days of the week or for certain periods of the day. The 800 Diet itself was developed by TV doctor Dr Michael Mosley

Whilst these diets can work for some people, there are many for whom fasting is not sustainable or comfortable.

We shouldn’t be punishing ourselves with diets but should instead find an enjoyable way of eating that sustains our health long term.

For most people, a fasting diet is going to be a short term fix.

The Paleo Diet involves consuming a lot of the lean meat it is believed our ancestors ate more than 10,000 years ago (image: Shutterstock)

Paleo Diet

The Paleo Diet involves consuming food and drink that our ancestors had access to in the Paleolithic era, which spanned from 10,000 to 2.5 million years ago. It involves eating lean meats, fish, fruits, vegetables, nuts and seeds and shuns foods that became popular with the advent of farming, for example, dairy.

This is a fad diet that cuts out food groups.

Any diet that does this is one to steer clear of.

Whilst it may help you lose weight, it will not be long term weight loss and it could lead to a restrictive way of eating that stops you getting all the nutrition your body needs.

Priya Tew’s top tips

I actually would not advocate you go on a weight loss diet or even focus on weight loss at all.

We know that a large percentage of diets just do not work.

Instead of going on a diet that is unlikely to last, focus on what you can add into your lifestyle to improve your health habits.

Eat more fruit and vegetables, switch to wholegrain versions of foods, increase your water drinking, move your body daily and improve your sleeping habits.

Practice tuning into your body’s needs when it comes to hunger, feeling full and getting satisfaction from your food.

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