We asked experts what they think of this diet that just jumped the pond.
But apparently there is no catch with Slimming World, a popular U.K.-based program that's now available in the U.S., says Yvonne Sanders, head of operations for Slimming World.
Word is, this very principle—eating your favorite foods without any weighing, counting, or measuring—is what makes the program effective. "Because you're eating many delicious foods that you enjoy (including small amounts of foods that most diets ban, like sweets), you never feel hungry or deprived, and are more likely to make healthy eating a choice instead of a chore," says Sanders.
Read on to find out how the Slimming World program works—and more importantly, if it will work for you.
Slimming World's Food Optimizing eating plan is based on the principles of energy density (the calories per gram in a food) and satiety (how filling a food is). The program encourages you to eat a long list of everyday foods that are low in calories and highly satisfying freely, without the need to weigh or measure portions. These are called Free Foods and include grub like fruits and veggies, lean meats, eggs, grains, and pasta. In the Slimming World guide, some Free Foods are marked with a P (Protein-rich) or an S (Speed) symbol. P foods are super-filling and keep you full longer, while S foods are low in calories yet satiating, helping you slim down at an efficient pace.
The other two nutritional pillars of the plan are Healthy Extras and Syns. Healthy Extras are measured amounts of foods that are higher in calories but contain vitamins and minerals that are important for weight loss and overall health—for example, foods that are high in calcium (think: milk and cheese) and fiber (whole-wheat bread and cereals). Participants are to nosh on two picks from the calcium-rich foods list and one from the fiber-based foods list daily.
Syns, short for synergy, include controlled amounts of treats, such as wine, chocolate, cake, potato chips, and sauces. Depending on your weight, height, and lifestyle, you'll be given a certain number of Syn points to spend each day. Each treat has a Syn value attached—so you'll have to cash in your Syns to enjoy that post-work glass of wine.
"It's the synergy between Free Foods, Healthy Extras, and Syns that makes the process of Food Optimizing unique, effective, and easy to live with in the long-term," says Sanders.
In conjunction with healthy meal plans, Slimming World encourages physical activity using a "baby steps" approach. The program wants users to work up to the ultimate goal of 30 minutes of exercise, five times a week. There are food and activity trackers to help you set goals, celebrate milestones, and stay motivated.
The best thing about the Slimming World program is that it encourages participants to nosh on a wide variety of nutrient-dense whole foods, with particular emphasis on fruits, veggies, and lean protein, all of which are satiety-promoting eats, says Edwina Clark, R.D., head of nutrition and wellness at Yummly.
It's also a less restrictive program, seeing as the list of free foods is fairly extensive, while other foods (dairy, grains, even sweets) are allowed in moderation. Unlike diets that ban certain foods or food groups, this isn't an elimination diet. All foods remain on the table (pun totally intended), which decreases the odds of experiencing the binge-guilt-repeat pattern that can strike—say, during an off day—and derail your weight loss efforts, says Clark. (Hit the reset button—and burn fat like crazy with The Body Clock Diet!)
Another big pro: Hydration with non-caloric beverages is a key principle of the program. "Weight-loss programs often neglect hydration," says Clark. "Meanwhile, it can have a profound impact on hunger and appetite control." Many of the pangs attributed to being famished, such as a noisy stomach and MIA energy levels, also strike when your body needs to be topped off with water. Staying properly hydrated is one of the easiest ways to keep your calorie intake in check without even trying.
Finally, there's a community page to share your weight-loss journey and success stories with others, giving you a strong support system with which to reach your goal weight. "This sense of community has been shown to be a beneficial model, especially when looking at other successful companies (Weight Watchers, Jenny Craig) which encourage camaraderie, inspiration, and healthy competition amongst members," says New York-based registered dietitian Tracy Lockwood.
A few caveats to keep in mind: Portion size guidance appears to be limited. So even though not having to count calories or obsess over portion sizes is a perk, keeping an eye on food quantity is a major component of weight loss, says Clark. Choosing inappropriately large portions of foods—even Free Foods—could lead to weight gain. And without mastering the basics of calorie counting and portioning, you may struggle to keep the weight off if you eventually decide to go rogue.
"While certain foods allowed on the Free Foods list may contribute to satiety, some are also calorie-dense and nutritionally poor," says Caroline Apovian, M.D., director of the Nutrition and Weight Management Center at the Boston Medical Center. "These include white noodles, potatoes, and rice, among others." These foods will provide very little to your body, nutritionally speaking, while contributing significantly to your daily caloric intake. "In addition, a few of these foods spike blood sugar, but don't have the protein or fiber content to sustain that energy, leading to an energy crash and cravings later on," she says.
Other questionable foods on the Free Foods list, like duck, goat, and lamb are high in pro-inflammatory saturated fats and should be consumed in moderation, says Clark. Same goes for processed meats, such as Canadian bacon, ham, and pastrami (also on the Free Foods list). Additionally, some of the free flavorings, like soy sauce and bouillon cubes, can be high in sodium and can cause water retention in some, particularly when consumed in excess.
There's also a heavy restriction on fats and oils that could sabotage your weight loss efforts in the long run, says Lockwood. "By not incorporating the appropriate amount of healthy fats in your diet, your body isn't provided with a sense of satiation, which could lead to grazing all day on foods that may not even fill you up, let alone satisfy you," she says. This could, ultimately, send your scale numbers in the wrong direction.
As long as you keep an eye on the higher-calorie free foods, there are plenty of positives that you can pull from the Slimming World program to give your weight-loss efforts a boost. "This is a good plan, and if someone is enjoying Slimming World and meeting their goals, they should stick with it," says Apovian. Adding more protein and vegetables to your diet, limiting sweets, and becoming more active are all proven weight loss strategies.
This program also teaches the importance of setting goals and planning ahead, which fosters commitment and accountability. The built-in social support, educational materials, and affordability are just icing on the (syn-worthy) cake.