UK Diet Statistics 2021

UK Diet Statistics 2021


What are the Most Popular UK Diets in 2021?

Almost two thirds of all Brits are on a diet most of the time according to Huffington Post, but which diet is the most popular? We conducted a keyword analysis with KWFinder to discover which diets are searched the most by the UK population, therefore indicating which are the most popular. We also analysed the popularity of the diets in social media on Instagram, evaluating the number of posts that are displayed with the hashtag of each particular diet.

Most Popular Diet in the UK 2021

How Popular is Slimming World in the UK 2021?

The Slimming world diet in essence consists of focussing  on eating mostly lean proteins, starches, fruits, and vegetables, as well as smaller portions of Healthy Extras, such as dairy, whole grains, nuts, and seeds. The Slimming World diet attempts to limit foods such as sugary drinks, alcohol, sweets and more by allocating a number of ‘Syns’ to each individual food item and a maximum number of ‘Syns’ that someone on the diet can consume per day.

Slimming World stands out as the most popular diet in the UK, with an average of 418,000 searches per month in the UK which is over double the search volume as its competitor in Weight Watchers. This is also supported by the fact that there are over 26 million posts on Instagram with the hashtag: ‘#slimmingworld’. This is much higher than the closest competitor, #Keto, with just less than 22 million posts. However, it is worth noting that Instagram posts are on a global scale, meaning that #slimmingworld is the most popular diet related hashtag globally. Furthermore, according to statistics, there are currently 900,000 active Slimming World members, highlighting the popularity of both the brand and the diet.

How Popular is Slimming World in the UK 2021?

How Popular is the Keto Diet in the UK 2021?

How Popular is the Keto Diet in the UK 2021?

The Keto diet is a low carbohydrate diet with a focus on consuming more good fats, putting the body in a metabolic state which is described as Ketosis. This lowers blood sugars and insulin in the body which is beneficial for your metabolic rate.

The phrase ‘Keto Diet’ is the second highest searched term that we analysed, with just short of 300,000 average monthly searches in the UK, making it the most popular non-branded diet that we considered. The popularity of the diet is also backed up by our key term research on Instagram, which highlighted that the hashtag ‘#keto’ has appeared in over 21 million posts. Even though users can make multiple posts with the same hashtag, the strength of the popularity of the diet on a global scale is exemplified by these figures and statistics. Moreover, a recent study of registered dietitians in the US found that the Keto diet is the most popular diet in America. While this study wasn’t based in the UK, it still proves the popularity of the health plan and the influence it has on those looking to get healthier.

How Popular is Weight Watchers in the UK 2021?

Weight Watchers also now known as WW is the most popular diet in the world, but when compared with the UK market, it is the third most popular. The diet works by each food item being assigned a number of ‘Smartpoints’, the higher the number of points, the worse the food item. This encourages users to maintain a healthy diet and avoid foods which are unhealthy in terms of sugar and fat content. Members are also encouraged to get fit and earn ‘fitpoints’ with support in the mobile application.

When analysing google search data, the term weight watchers is searched on average 141,000 times per month in the UK which makes it the 3rd most popular diet amongst brits. Supporting this, according to Instagram tags, there has been almost 10 million posts with the tag ‘#weightwatchers’ uploaded. According to the Healthline, 600,000 members joined WW in just 2017 alone, aiding the point of the popularity of the diet plan.

How Popular is Weight Watchers in the UK 2021?

How Popular is Intermittent Fasting in the UK 2021?

How Popular is Intermittent Fasting in the UK 2021?

Intermittent fasting is a dietary method that incorporates periods of eating and periods of not eating anything (fasting). The primary focus on this health plan is based on when you eat and not what you eat with the theory being that a shorter eating duration will lead to less calories consumed over the course of the day. This method is effective if you don’t compensate by overeating in the time slots allocated for food consumption. According to Hopkins Medicine, large time periods with no food make the body use all of its sugar stores and begin to burn fat for energy. This is known as metabolic switching.

Intermittent fasting is the 4th most popular diet plan based on search results in the UK (134,000 average monthly searches), with Weight Watchers just beating it to the 3rd position by only 7000 searches per month. However, the number of posts with the hashtag ‘#intermittentfasting’ has a much lower number of posts on Instagram than ‘#weightwatchers’ with less than 4.5 million posts. This could be down to the popularity on the global scale or potentially due to the lack of shareability of posts with this hashtag. Additionally, according to the International Food Information Council Foundation, intermittent fasting was the most popular diet in 2020 in the US. However, intermittent fasting is sometimes seen as a eating schedule rather than a diet, explaining why search results for the term may be lower.

How Popular is 5:2 Fasting in the UK 2021?

The 5:2 diet is a form of intermittent fasting where somebody can eat as normal for 5 days in the week, but fast on 2 of the days in the week, eating a maximum of around 500-600 calories per day. This diet is effective as insulin levels are reduced and improves insulin sensitivity. However it is only effective if on the off days, you don’t overeat and maintain a balanced diet.


The search term ‘5:2 diet’ was searched almost 26,000 times per month and has almost 140,000 posts on instagram with the hashtag ‘#52diet’. The 5:2 diet is currently the most popular form of intermittent fasting.

How Popular is 5:2 Fasting in the UK 2021?

How Popular is 16:8 Fasting in the UK 2021?

How Popular is 16:8 Fasting in the UK 2021?

The 16:8 diet is also a form of intermittent fasting, however, it is the lesser popular method of the two covered in this article. The diet entails fasting for 16 hours a day and consuming all calories in the remaining 8 hours of the day.


The search term ‘16:8 diet’ is searched on average 10,300 times per month and there are just over 28,000 posts on instagram with the hashtag ‘#168fasting’ which is the most popular hashtag surrounding the form of intermittent fasting.

Other Popular Diets in the UK 2021

Also covered by our research and making the top ten most popular diets in the UK based on search volume in the UK include: the Exante Diet, Cambridge Diet, Slim Fast, Paleo Diet and the Atkins Diet. 

  • The Exante Diet accumulates 39,500 average monthly searches and has over 122,000 posts on instagram with the tag ‘#exante’.


  • The Cambridge Diet generates 31,800 average monthly searches and has over 300,000 posts on instagram with the tag ‘#cambridgediet’. The increased popularity on Instagram when compared to ‘#exante’ may be due to the Cambridge Diet being more popular worldwide or alternatively, being more easily shared on social media.


  • Slim Fast gains 27,600 average monthly searches in the UK and is the third most popular branded diet behind Slimming World and Weight Watchers. On Instagram, there are more than 260,000 with the tag ‘#slimfast’.


  • The Paleo Diet has 25,700 average monthly searches. However, notably, there are over 15 million posts on Instagram with the hashtag ‘#paleo’ and almost a further 2 million posts with the hashtag ‘#paleodiet’. Furthermore, globally there are 270,000 monthly searches for the term ‘Paleo Diet’ highlighting its popularity on the international scale. Therefore, this implies that the Paleo diet plan is yet to gain the average popularity in the UK that it experiences in countries like America.


  • The Atkins Diet has 20,000 average monthly searches and appears in over 1 million posts on Instagram, once again highlighting the shareability and global reach of the health plan.

Summary: Diet Statistics UK Roundup

To conclude, in the UK, Slimming World is by far the most popular diet plan, however, when compared with the likes of the US, diets such as Weight Watchers, Intermittent Fasting and the Paleo diet appear to be the most popular. The Keto diet and Intermittent fasting are vastly the most searched for non-branded diets in the UK, with Keto generated a large volume of social media coverage on Instagram.


We hope these statistics have been helpful and interesting to you and additional resources have been listed below.

Additional Resources


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