Slimming World Diet Analyzed

Fact Checked

A Program That Works By Focusing On “Food Optimizing”

If you’re looking to lose weight the chances are that you’ve looked into various diets, from Atkins to Weight Watchers and everything in between. These kinds of organized diets break things down into easy to understand, manageable steps so users can take their weight loss one bite-sized chunk at a time.

Launched in 1969, Slimming World is a weight loss organization that runs a highly successful and critically acclaimed dieting programs for people in the UK and the USA.

The main part of a Slimming World plan focuses on Food Optimizing – this is what makes or breaks a weight loss plan. A survey of over 2000 people following Food Optimizing found that 78% of them bought more fruits and vegetables than before, 74% ate less fatty food, 61% ate less sugary food and 58% ate fewer ready meals and takeaways.

Over 80% of people also reported improvements in their health such as improved digestive function and fewer aches and pains.

There are three things to consider when starting food optimization in a Slimming World plan:

1. Free Foods

Described by Slimming World as ‘the key to your success’, these are foods that participants can eat as much of as they like. Free Foods include vegetables; lean meat; potatoes; pasta; fruit; fish and eggs.

The Slimming World plan takes into account how satisfying a food is compared to the calories and nutrition provided; Free Foods are those that provide high satiety and relatively few calories so the consumption of these naturally leads to reduced calorie intake.

A typical meal consisting entirely of free foods would be steamed vegetables with boiled potatoes and grilled chicken breast, or a mushroom omelette with a side salad.

2. Healthy Extras

Healthy Extras are foods that are considered important in a balanced diet but contain more calories than the Free Food options.

In the Healthy Extras section are foods such as cheese, milk, cereals and whole wheat bread, providing calcium and fiber to the Slimming World participant’s diet. Healthy Extras are also often things used to cook with Free Foods, for example cooking potatoes in butter or using olive oil as a dressing on a green salad.

3. Syns

Syns are the foods that are highest in calories (and often sugar) such as alcohol, crisps, sweets, chocolate, biscuits and cake. Slimming World participants are allowed a certain number of Syns to make sure nobody feels deprived and to ensure you don’t go wildly off track after craving a ‘forbidden’ food.

Slimming World does not recommend that users ‘cancel out’ Syns with exercise or use exercise as a way to ‘earn’ more Syns, but rather to simply enjoy small amounts of these foods while incorporating exercise into their daily lives as a healthy and sustainable choice.

They Reward Positive Changes

Somewhat unique to Slimming World is that it focuses on rewarding and praising those who are seeing weight loss results, no matter how small.  Slimming World refers to itself as “a positive lifestyle program”, hence why the program actively makes an effort to celebrate customers’ milestones, whether it be the first pound of weight loss or six months’ of continued healthy diet and exercise.

The theory is that with positive reinforcement, and by boosting the self-esteem of fellow Slimming World dieters, the chances of the follower returning to their old negative eating patterns are minimized even further.

IMAGE group sessions promise to never be judgmental or embarrassing; rather they offer a supportive community and environment in which people can share the same goals, struggles and successes.

How Slimming World’s IMAGE Therapy Sessions Work

Weekly group support sessions known as IMAGE therapy (Individual Motivation and Group Experience) are an iconic part of the Slimming World program. Experienced Consultants, each of whom have already completed Slimming World successfully, lead the sessions with current dieting participants. Everyone at the session is weighed to keep track of how their progress is going; successes are celebrated and individuals can ask for help and support with areas they are finding difficult.

You’ll share recipes and tips on eating out and meal planning, get help recognizing where your weight loss journey could be made easier and of course meet like-minded people and new friends. Other events at IMAGE Therapy include raffles, motivating talks and even social evenings out with the group.

You’ll Be Following The Body Magic Exercise Program

A physical activity program that complements Slimming World’s Food Optimizing plan, Body Magic helps participants shed pounds quicker by introducing exercise in a gentle and manageable way. Using psychological and scientific principles of behavior of change, Body Magic helps users to find their personal motivations for weight loss and to identify the most enjoyable and sustainable ways of bringing physical activity into their lives.

The program follows government recommendations of completing 30 minutes of exercise five times per week and is tailored to be suitable for everyone no matter their fitness level or weight. Users log their FIT data (Frequency, Intensity and Time) and work towards Bronze, Silver, Gold and Platinum certificates to acknowledge their hard work and achievements.

Slimming World works to not just get people active, but incorporate sustainable lifestyle changes that go beyond just a fad diet. Consultants work with users to overcome psychological barriers to exercise, build confidence, redefine what counts as ‘activity’ and continue to support them until active living becomes a natural lifestyle.

Slimming World has great results with its Body Magic program. 37% of participants said they had more energy than before; 33% said that they had a new-found enjoyment of exercise; 31% said they had improved their posture; 25% reported an improvement in mood and decreased stress and 22% said they slept better after increasing their exercise.

Does Slimming World Work For Slimming?

The Slimming World program is ultimately a sustainable, low-calorie diet and lifestyle plan that, if followed correctly, will undoubtably help the follower lose weight (the exact amount of weight depends entirely on the individual).

Slimming World state that their unique approach to weight loss is based on top quality science including nutritional research and behavioral psychology; it’s no wonder then that the diet organization has an excellent reputation for delivering results.

The average Slimming World member losing almost 4kg after three months, and for participants committing to 75% or more of the weekly group sessions, the average loss was almost 7kg! Over a 12-month period those members attending at least 75% of sessions lost an average of 12.7kg, making the program a highly effective weight loss plan.

Slimming World continually assesses their program and policies to ensure they’re staying up to date with the best nutritional and weight loss research in order to deliver maximum benefit to its users.

Slimming World’s Optional Ready Meal Products

Slimming World Ready Meals

Lots of people assume that by becoming a paid member of weight loss organization such as Slimming World that they’ll also be required to spend a fortune on the program’s own-brand foods (we’ve seen this many times in the past with programs like Nutrisystem and the South Beach Diet), but thankfully Slimming World does not require anything more from its members beyond the membership fees.

You’ve probably seen many of Slimming World’s food products in the low-calorie isle of your local Iceland – these are not required by the program, but instead they’re there to simply make sticking to the program itself easier and more convenient (as they remove the need to manually prepare low-calorie meals yourself).

As long as you’re able to ensure that the meals you’re making yourself are low in calories, you can use normal groceries.

Here are two examples of how a Slimming World day can look:

Slimming World Meal Plan 1:

  • Breakfast: Two scrambled eggs, grilled tomatoes, mushrooms sautéed in olive oil and wholemeal toast.
  • Snack: A tropical fruit salad of watermelon, mango, papaya and banana with a squeeze of lime and passionfruit.
  • Lunch: Tuna salad with boiled egg and wholegrain brown rice, plus a couple of squares of dark chocolate.
  • Snack: A homemade smoothie ice lolly made from frozen bananas and raspberries.
  • Dinner: Spaghetti bolognese with lean chicken mince instead of beef, sautéed in low-calorie spray with chunky Mediterranean vegetables and accompanied by a small glass of red wine.

Slimming World Meal Plan 2:

  • Breakfast: Homemade muesli with Greek yoghurt and fresh fruit.
  • Snack: Dried vegetable crisps and an apple.
  • Lunch: Hummus and falafel with a fresh green salad and crudités.
  • Snack: A banana.
  • Dinner: Chickpea and sweet potato curry with brown rice, green beans and carrots, plus a cookie.

Memberships Types

In the UK, members have a choice of group or online membership starting at £4.95 per week. In the US users can purchase a three-month membership for $30 or one month for $15.

When you join, you’ll get:

  • Access to a friendly online group run by an experienced Consultant.
  • 24/7 access to a supportive online Slimming World community.
  • Hundreds of healthy recipes and menu plans.
  • A meal planning and activity tool.
  • A complimentary book to guide you through the Slimming World plan.
  • An app for access to the Slimming World community and to enter your weekly weigh-ins.


Slimming World is a highly successful diet and weight-loss organization that has helped over a million people make improvements in their health and sustainable changes in their lifestyle.

Rather than a fad diet, Slimming World created a whole support network for those looking to lose weight, ranging from sound dietary advice to group therapy sessions. The aim of Slimming World is not just to instruct followers on how to lose weight by changing up their diet and lifestyle, but to help them implement and understand the changes they make, so it can be carried on over the long term.

The foods suggested by Slimming World are everyday items that require no specialist knowledge of nutrition or cooking, making this program a great one for people wanting to lose weight quickly, safely and with the support of people who have done it before them.

While it’s not free to join, it’s hardly expensive (costing less than £5 per week). What’s more, Slimming World don’t try and milk their customers for further revenue by forcing them to buy a bunch of additional products they don’t need – the Slimming World products are entirely optional!

In the end, the proof really is in the pudding – though you’ll not be eating much of that while doing Slimming World!

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Fact Checked

This article has been reviewed and fact-checked by a certified nutritionist, and only uses information from credible academic sources.