What Is Slimming World?

Find Out If Slimming World USA Is Likely to Work for You

Close-Up Of Food On Table
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Slimming World is a popular weight loss program based in the United Kingdom. Now available for customers in the United States, the plan teaches members to shop for and eat whole, nutritious foods and limit their intake of fatty, sugary, or processed foods. Motivational support and guidance to encourage an active lifestyle are also vital components of the program.

What Is Slimming World?

Slimming World was founded in 1969 by Margaret Miles-Bramwell, a British dieter who struggled with the frustration and guilt of failed weight loss attempts. The program was only available to customers in the UK until 2016 when it became available to dieters in the United States.

The Slimming World program is based on the belief that confidence-building support and healthy food choices can produce weight loss without counting calories or severely restricting food intake. To follow the program, customers sign up for a membership (roughly $10/month) that gives them access to a weekly support meeting and other resources that help them to build meals and practice daily habits that boost weight loss.

Slimming World is available for consumers aged 18 and over with a BMI of 23 or above. Those who have certain medical conditions such as high cholesterol or diabetes may also use the plan with guidance from a physician.

Vegan and vegetarian eaters will also find support on the Slimming World diet. The program is not recommended for women who are pregnant or anyone with an eating disorder.

How Does Slimming World Work?

If you sign up for a Slimming World membership, your weight loss plan will encompass three key components: a food plan, a support plan, and an activity plan.

Slimming World Food Plan

Unlike many popular commercial diets, there are no packaged foods to buy, no shakes or meal-replacement drinks, and no specific calorie goals to meet. Instead, Slimming World members practice Food Optimizing to avoid hunger and stay satisfied. Food Optimizing means that you build meals around foods that fall into one of three categories:

  • Free Foods: Members do not measure or restrict these foods. Free foods include lean meat and poultry, fish and seafood, potatoes, pasta, rice, eggs, beans and lentils, fruits and vegetables, and other foods that are low energy dense (low in calories) and highly satiating (more filling). Some Free Foods are considered Speed Foods and members are instructed to include a certain number of Speed Foods in each meal. Speed Foods are foods that are lower in calories but high in nutrition.
  • Healthy Extras: Members will need to measure and limit foods in this category. Healthy Extras include calcium and fiber-rich foods such as cereal, cheese, milk, and whole grain bread products. These foods provide nutrition and boost satiety, but increase daily caloric intake. Healthy Extras are enjoyed in smaller amounts.
  • Syns. These are foods that some might call indulgences. Syn stands for "synergy," and the word represents all of the treats that bring us enjoyment and help us to stay on track with our diets. Syns include foods like sugary baked goods, candy, ice cream, or wine.

    Even though the program promises that you don't have to measure foods, count calories, or eliminate certain foods, there are rules you need to follow if you want to be successful. So it is realistic that you may feel deprived or struggle as you adjust to eating new foods and limiting or avoiding certain comfort foods that are not on the Free Foods list. But many of the foods that are emphasized on the plan are nutritious and recognized by most health experts to be important for a healthy diet. They are also foods that are likely to help you feel full after eating so you don't get hungry.

    Slimming World Support

    A key component of the Slimming World plan is the support that is offered through the online tools and community. During the first 12 weeks of the program, you'll have access to a structured program that helps you learn about the eating plan. You will also sign up for an online "Slimming Group" that meets at a time that is convenient for you.

    Participation in the Slimming Group is the cornerstone of this program. According to a company statement, "the program is built upon a deep understanding that people who are overweight carry a double burden: the burden of weight itself and the far heavier burden of guilt, self-criticism, and low self-esteem." For this reason, members support each other during the one-hour meeting where the focus is on lifting shame and building confidence.

    Each session is directed by a Slimming World-trained consultant. Before each session, members may choose to log their weight change. No one is required to reveal their progress or their weight to the other group members. However, if they do so, they can expect to get support and feedback regarding their success or struggles. Questions are answered during the meeting and members share tips to help each other stay on track.

    Slimming World Activity Plan

    Although physical activity is strongly encouraged, exercise is not required on the Slimming World plan. In fact, the company acknowledges that exercise is not required to lose weight. But they encourage members to boost daily activity to slim down and to keep the weight from coming back.

    To increase physical activity, Slimming World promotes Body Magic, their program to burn more calories by incorporating more movement into your daily routine. The program was developed in collaboration with Ken Fox, Emeritus Professor of Exercise and Health Sciences, University of Bristol, UK.

    As a Slimming World member, you'll use evidence-based strategies to gradually increase daily movement and build your own sustainable activity plan. The goal of the program is to eventually participate in 150 minutes of moderate intensity activity per week.

    There is no specific exercise program provided but members get an online interactive activity planner that is backed up by a series of rewards. Members are encouraged to explore activities that they already enjoy. 

    Is Slimming World Effective?

    As a Slimming World member, you can expect to put a great deal of time and energy into changing your lifestyle and your daily habits. But the activities that you are encouraged to participate in are grounded in a great deal of sound evidence. So for many dieters, this may be a smart path to sustainable weight loss.

    Science Behind Slimming World

    Several studies published in peer-reviewed journals or presented at major conferences have supported Slimming World as an effective weight loss program:

    • A study published in BMC Public Health evaluated weight change outcomes in 1,356,105 adult participants during their first three months’ attendance in Slimming World. Researchers reported that average amount of weight loss was approximately 8.5 pounds, with average attendance reported at 7.8 sessions. For participants attending at least 75 percent of possible weekly sessions, average weight loss was nearly 15 pounds.
    • A study presented at the UK Society of Behavioural Medicine in 2016 evaluated 356 Slimming World participants (all women) after three years.  At the time of the survey, those currently attending a Slimming World group had lost 9.6 percent body weight on average, while those no longer attending were currently 4.4 percent lighter compared to when they first joined a group.
    • A study published in the Journal of Human Nutrition and Dietetics evaluated 67 male members of Slimming World and found that men who were members for 12 weeks lost an average of 9.2 percent of excess weight and at 24 lost an average of 10 percent of excess weight.

    It is important to note that most of the published research findings and statistics promoted by Slimming World are also funded by the company and/or conducted by the Slimming World research team. But the basic foundation of their program (building a nutritious eating and sustainable activity plan) is supported by other well-respected agencies, including those in the United States.

    For example, the structure of the eating plan follows similar guidelines as the USDA's Choose My Plate program, which encourages Americans to fill their plate with vegetables, fruit, whole grains, and lean meat. Additionally, the program encourages dieters to limit their intake of empty calories and to fill up on satisfying whole foods (with an emphasis on fruits and vegetables) to promote wellness, a nutritional approach supported the True Health Initiative.

    Lastly, the program encourages members to incorporate 150 minutes of moderate exercise per week, a recommendation supported by the American College of Sports Medicine and other health agencies.

    Will I Lose Weight on Slimming World?

    The Slimming World program is designed to support weight loss at a rate of 1-2 pounds per week. Most experts agree that this is a reasonable and sustainable rate at which to lose weight. However, whether or not you slim down on the program and the amount of weight that you lose will depend on a few factors.

    While the foundation underlying Slimming World's food, support, and movement plan is sound, the program may take more work than other popular commercial programs like Jenny Craig or Nutrisystem. No foods are provided, so members must learn to prepare their own meals and make numerous food choices throughout the day. For some, this approach may be overwhelming. In simple terms, this program doesn't provide the convenience or flexibility offered by other weight loss systems.

    In addition, members need to have access to reasonably healthy goods and services for this program to work. If you don't have a market nearby where you can purchase nutritious food, and if you don't have time to prepare meals, you may have a hard time sticking to the plan. You also need to find the time and energy to create a program to increase daily movement for the activity plan to be effective.

    Lastly, the program has been criticized by the National Health Service in England for not providing enough information to members about calories and portion sizes. The organization did, however, give the program a relatively good rating, stating that the meals are generally balanced.

    Many diet experts would argue that the key to sustainable weight loss is a strong personal commitment to healthy living and a foundation of nutritious food choices. So if you have the time and energy to learning about smarter eating, and if you have the motivation to build and sustain a pattern of daily movement, this may be a smart program for you.

    A Word From Verywell

    No diet or weight loss program works perfectly for everyone. So before you choose to invest in a commercial program, it's smart to evaluate a few of them to compare. Ask yourself key questions about your lifestyle, your budget, and your past dieting history to make sure you choose the program that is most likely to work for you.

    Keep in mind that the weight loss program you choose may not be the most popular plan, or the plan that has worked for your friends and family members. But if it is an eating and lifestyle plan that works well with your daily routine, it's more likely that you will be able to stick to it long enough to see results on the scale and then adopt a maintenance plan to keep the pounds off for good.