The SlimFast Diet: Pros, Cons, & A Sample Meal Plan

Boost your weight loss with this meal replacement that is rich in whey protein, minerals, and vitamins.

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Written by , MSc (Nutrition), CDE Priyanka Sadhukhan MSc (Nutrition), CDE linkedin_icon Experience: 8 years
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SlimFast diet is the newest diet plan that everyone is raving about. This diet plan has helped many people lose weight without any major food restrictions. It is a meal replacement diet plan founded by S. Daniel Abraham in 1977. Since then, it has changed the weight loss game.

The SlimFast diet plan allows you to have three generous meals with intermittent healthy snack bars. This helps boost your metabolism, curb untimely hunger pangs, and improve satiety. This meal replacement shake is made of whey protein, vitamins, and minerals. It is also low in calories and helps achieve healthy weight loss.

This article tells you everything about the SlimFast diet, a sample diet plan, and the pros and cons. Swipe up!

What Is The SlimFast Diet?

Meal replacement bars and drinks for SlimFast diet
Image: Shutterstock

The SlimFast diet is a short-term weight loss program that uses meal replacement shakes, porridges,and meal replacement bars to help one shed fat. It is simple, convenient, easy to follow, and can help you get that full body transformation you desire.Its basic principle is to replace one or two meals with SlimFast shakes, enjoy real healthy foods of your choice, and include 100-calorie snack bars in between meals to curb hunger pangs and promote satiety. It focuses on calorie control, maintaining a healthy lifestyle, and even following a good fitness routine for effective weight loss.

SlimFast includes different formulas to add variety to the diet. It has different programs based on the need – including the SlimFast Keto Shakes, Diabetes Weight Loss Shakes, Advanced Energy System to boost energy levels, and Advanced Nutrition Smoothies Mix that is ideal for the low-carb and low calorie diet. It also contains a starter pack for those who want to kick start their weight loss journey. The Slim Fast Advanced Vitality Pack supports metabolism, alleviates fatigue and tiredness, and helps with weight loss.

The next section helps you understand how the SlimFast diet works.

How Does The SlimFast Diet Work?

The SlimFast diet is an upgraded weight loss program that focuses on the 3-2-1 plan. The principle of this approach is to include 3 healthy SlimFast snacks, 2 healthy SlimFast shakes, and 1 healthy meal of your choice.  By replacing regular meals and snacks with the low-calorie variants, you will be able to lose weight and kick start your body’s metabolic processes (1).

On average, the SlimFast diet provides 1200 calories for women and 1600 calories for men per day. The SlimFast diet plans six meals a day through one full meal (500 calories for women, 800 calories for men), two shakes or smoothies, and three 100-calorie snacks. This diet kick starts your metabolism, curbs hunger, and offers complete satisfaction.

SlimFast offers a variety of 7-day meal planners that can be downloaded from their website. It also has a 30-minute workout regime to suit your weight loss goals.

Can It Help With Weight Loss

The SlimFast diet may promote weight loss.
Image: Shutterstock

If followed as per the guidance, the SlimFast diet does help with weight loss. It works by lowering one’s calorie intake and encouraging one to replace their high-calorie conventional meals with protein-rich shakes, snack bars, and porridges.

A study showed that a very low-calorie diet with restricted carbohydrates (3-10% of total calorie intake) and restricted fat helps lower body weight by 8% in the short-run (2), (3).

A study in the Journal of Nutrition showed that people on the meal replacement SlimFast diet plan lost weight effectively when compared with those on a conventional but structured diet plan (4).

A study published in the British Medical Journal compared the effectiveness of four commercial weight-loss programs in obese and overweight individuals. Dieters on the SlimFast diet plan lost an average of 6 pounds in 4 weeks, along with significant fat loss (5).

Another study showed that the SlimFast meal replacement therapy decreased body weight by 7% and reduced BMI from 40 kg/m2 to 37 kg/m2 over a six-month treatment period (6).

SlimFast shakes are rich in protein. One sachet of the shake contains 26 grams of protein per serving. It contains whey protein isolates for optimum supply. Studies show that a high-protein diet increases leptin sensitivity and results in significant weight loss (7).

Furthermore, one review of six studies showed that meal replacement programs like that of SlimFast may result in weight loss in long-term weight management (8).

protip_icon Quick Tip
The intake of high-protein foods, including meat (lean beef), helps decrease hunger pangs (11).

Liz, a food, fitness, and lifestyle YouTuber shared her experience of doing the SlimFast diet for 7 days. She said, “I actually lost 2.5 pounds! Which is good, look I’m actually shocked with that (i)!. However, she admitted that she wouldn’t want to do this diet beyond two to three weeks because it worked with a very high calorie deficit.

In the following section, we have listed the foods you can eat on the SlimFast diet.

Foods To Eat

The main focus of the SlimFast diet is to make meal replacement shakes a part of the major meal. You also will have healthy 100-calorie snacks that help curb hunger pangs. The SlimFast balanced diet emphasizes filling your plate with 50% of vegetables and fruits, 25% of lean protein, and the rest 25% with whole grains.

The following options will help you plan your meals:

    • Vegetables: cucumber, tomato, asparagus, spring onion, artichokes, baby corn, bean sprouts, Italian beans, cherry tomatoes, and bell peppers
    • Leafy vegetables: Spinach, kale, celery, and Swiss chard
    • Fruits: apple, banana, pear, berries, and grapes
    • Lean meats: lean cuts of poultry, beef, and bacon
  • Dairy and dairy products: low-fat yogurt, Greek yogurt, and low-fat milk
  • Legumes: chickpeas, black beans, and lentils

protip_icon Quick Tip
Dairy products provide calcium and protein, which may help in appetite control (12). This way, dairy products in the SlimFast diet may help with weight loss.

In addition to including these foods in your diet, you also need to avoid certain foods.

Foods To Avoid

No foods are restricted in the SlimFast diet plan. But, as it focuses on limiting your calorie intake, the following food groups must be limited or even avoided.

  • Sugar and sugary products
  • Aerated drinks or carbonated beverages
  • Processed foods
  • High-fat fried snacks
  • Baked foods
  • Alcoholic beverages (although a glass of wine is allowed now and then)

The following section includes a sample diet plan. It will help you prepare your meal within an estimated calorie budget.

A Sample SlimFast Diet Plan

Diet Plan 1

MealsFoods To Be Included
BreakfastChunky Chocolate Flavor Shake
Snacks-11 apple
LunchSummer Strawberry Milkshake
Snacks-2Cheddar Flavor Bites
DinnerSmoked mackerel+ beetroot, potato salad with 1 tsp olive oil dressing
Snacks-3SlimFast Chocolate Caramel Treat Snack Bar

 Diet Plan 2

MealsFoods To Be Included
BreakfastSlimFast Creamy Milk Chocolate Shake
Snacks-1SlimFast Sour Cream & Chive Flavor Pretzels
LunchCafe Latte Flavor Shake
Snacks-2Heavenly Chocolate Delight Snack Bar
DinnerMushroom asparagus and bacon risotto
Snacks-3SlimFast Chocolate Caramel Treat Snack Bar

 Diet Plan 3

MealsFoods To Be Included
BreakfastSlimFast Porridge
Snacks-1Cucumber and celery stick with hummus bowl
LunchSpicy barbeque chicken salsa and potato wedges
Snacks-2A small bowl of berries mix
DinnerSlimFast Chunky Chocolate Flavor Shake
Snacks-3SlimFast Cheddar Flavor Bites

 The next section shares some recipes that can add some variety to your routine. Enjoy the healthiest foods within your calorie budget.

Healthy SlimFastRecipes

1. Mediterranean Greek Salad

Mediterranian Greek salad for slim fast diet
Image: Shutterstock

Serves: 2; Prep Time: 15 min; Cooking Time: 5 min; Total Time: 20 min

  • 1 large cucumber
  • ½ cup chopped sun-dried tomatoes
  • ½ cup chopped Roma tomatoes
  • ½ cup sliced red onions
  • ½ cup crumbled feta
  • 3 tablespoons sliced black olives
  • 2 tablespoons olive oil
  • 3 tablespoons lime juice
  • ¼ teaspoon black pepper
  • Salt to taste
How To Prepare
  1. Use a vegetable peeler to shave the cucumber into thin ribbons.
  2. Toss the cucumber ribbons, Roma tomatoes, sun-dried tomatoes, feta, and black olives in a bowl.
  3. Add olive oil, lime juice, black pepper, and salt.
  4. Toss well before eating.

2. Savory Herb Whole Grain Crackers

Savory herb whole grain crackers for slim fast diet
Image: Shutterstock

Serves: 6; Prep Time: 15 min; Cooking Time: 15 min; Total Time: 30 min

  • 1 cup whole wheat flour
  • 2 teaspoons sesame seeds
  • 2 teaspoons mixed herbs, like oregano and basil
How To Prepare
  1. Make a stiff dough with the ingredients and water.
  2. Roll the dough out into thin tortillas (Indian flatbreads or chapatis) and cut them into strips.
  3. Bake at 450°F for 10-15 minutes until they are crisp.

3. Chicken Breast With Brussel Sprouts

Chicken breast with brussel sprouts for slim fast diet
Image: Shutterstock

Serves – 2;Prep Time – 15 min;Cooking Time – 25 min;Total Time – 40 min


  • 8 ounces boneless chicken
  • 3 teaspoons salt
  • 2 stems broccoli
  • 2 spoons olive oil
  • 2 spoons fresh lemon juice
  • ¼ spoon freshly ground pepper
  • 3 cups thinly sliced Brussels sprouts
  • 2 stalks celery
  • ¼ cup hazel stalks
  • ¼ cup flat-leaf parsley
  • 1 ounce parmesan cheese

How To Prepare

  1. Cook chicken with salt in a saucepan. Cover with water and let it boil.
  2. Let it stand for 15 minutes.
  3. Drain the chicken and let it cool aside.
  4. Remove the broccoli stems in the meantime.
  5. Whisk lemon juice, oil, celery, salt, and pepper.
  6. Add the broccoli stems and Brussels sprouts.
  7. Add hazel and parsley too.
  8. Add chicken with dressing.
  9. Divide among 4 bowls.

SlimFast Shopping List

Following a SlimFast diet plan is easy. You need to start with stocking up on SlimFast products along with other foods. We have included them below.

  • SlimFast meal replacements: SlimFast meal shakes, cookies, meal replacement bars, porridge mixes
  • Vegetables: Broccoli, tomatoes, sweet potato, potato (in moderation), asparagus, leafy greens, and Brussel sprouts, capsicum, cabbage, cauliflower, aubergine, all gourds, and okra
  • Lean meats: Beef, poultry, pork, and lamb
  • Fruits: Apple, pear, papaya, cantaloupe, banana, berries, and grapes
  • Dairy and dairy products: Low-fat milk, cottage cheese, unsweetened nut milk, and yogurt
  • Whole grains: Quinoa, steel-cut oats, brown rice, barley, and buckwheat
  • Nuts: almonds, Brazilian nuts, pistachio nuts, pecan nuts, walnuts, pumpkin seeds
  • Oils: Olive, avocado, and cold-pressed coconut oils

The SlimFast diet plan is simple and effective. Like every other diet plan, it does have its share of pros and cons. We will explore them in the upcoming sections.


  • The SlimFast diet plan is an effective weight loss program. It gives results if one follows it properly. Reduction in body weight may alleviate high blood pressure, reduce cardiovascular disease risk, and help in the treatment of diabetes (8), (9),(10).
  • The SlimFast diet schedule also encourages one to exercise for at least 30 minutes a day. Studies have shown that meal replacement plans, along with a structured exercise regime, help shed pounds and improve different biochemical markers (10).


  • Over-dependence on meal replacement shakes could keep you away from natural and seasonal food sources.
  • The program is expensive to be followed over extended periods.
  • It could limit healthy cooking options.
  • There is no mention of portion control in healthy meal plans.
  • It does not mention weight maintenance plans.
  • The diet mostly focuses on restricting calories with a high-protein meal shake. It may not be suitable for people with kidney disorders, gout, etc.

Should You Try The SlimFast Diet Plan For Weight Loss?

The SlimFast diet plan is an excellent way to reduce pounds and get your body in shape. It is a simple plan that works without compromising on your meal intake. It emphasizes eating at regular intervals to boost your metabolism and curb hunger pangs – promoting healthy weight loss. The SlimFast meal replacement diet plan easily fits into your busy schedule and gives you the exact results that you wish for. However, there is no scientific evidence on the long-term effectiveness of the SlimFast diet plan. Hence, it is recommended you check with your doctor prior.

The SlimFast diet may aid in weight loss. However, it may not be for everyone as the products are highly processed and may be unsuitable for people with food sensitivities. Check out the next section for SlimFast meal replacement alternatives that you can try.

Alternatives To SlimFast

Here is a list of some homemade alternatives:

  • DIY Shakes: Make your own meal replacement shakes using fresh ingredients and keeping your food sensitivities in mind. Experiment with low-calorie ingredients such as protein powder, unsweetened almond milk, raw cacao powder, and flax seeds.
  • Low-Calorie Cookies: Make low-calorie cookies at home with ingredients such as oatmeal, peanut butter, or Greek yogurt to keep you full.
  • DIY Meal Bars: Make your own meal bars at home using high-protein ingredients such as quinoa, nuts, seeds, soy, or muesli.

Infographic: The SlimFast Diet – Foods To Eat And Snack Ideas

The SlimFast diet is a well-known weight loss strategy that has been around for a while. While this method can help you lose weight and improve your health, the best results come from following the diet to the T, which includes knowing which foods to eat and which to stay away from. Check out the infographic below to learn more about the foods you can eat while following this diet.

the slimfast diet foods to eat and snack ideas(infographic)

Illustration: StyleCraze Design Team

The slim fast diet has gained the attention of many, especially all the weight watchers out there. This diet helps one lose weight, and the lost weight is maintained. This diet is based on meal replacement bars, protein shakes, and porridges that help shed fat. The calorie choices are lowered in this diet. You can, however, include many vegetables, leafy greens, fruits, and dairy products in this diet. On the other hand, processed foods, carbonated drinks, baked foods, and alcoholic beverages are strictly restricted. You can include any of the recipes mentioned in this article in your slim fast diet. This diet not only aids in visible weight loss but also caters to your overall health.

Frequently Asked Questions

How many carbs are in SlimFast?

Depending on the kind of SlimFast product you opt for, it may have between 7-25 gms of carbohydrate content.

Does SlimFast work in 2 weeks?

With an estimated weight loss of 1-2 pounds per week, you can begin to notice changes around 2 weeks with SlimFast.

Is Slim Fast keto effective?

The SlimFast Keto Shakes are especially made for a keto-friendly diet routine.

Key Takeaways

  • The Slimfast diet not only helps you lose weight but also helps maintain it.
  • Made up of whey protein, multivitamins, and minerals, this low-calorie meal replacement helps boost your metabolism while keeping your hunger pangs in check.
  • Available in different formulations, these cater to different diet plans, address diabetes, support healthy eating and weight loss, and increase vitality.
slim fast diet

Image: Stable Diffusion/StyleCraze Design Team

The SlimFast diet is an easy and much healthier choice compared to other diets. Watch the video below to see how it compares to counting calories and decide which one is best for losing weight. Check it out now!

Personal Experience: Source


Articles on StyleCraze are backed by verified information from peer-reviewed and academic research papers, reputed organizations, research institutions, and medical associations to ensure accuracy and relevance. Read our editorial policy to learn more.

  1. Guo, Xiaohui et al. “Effects of a Meal Replacement on Body Composition and Metabolic Parameters among Subjects with Overweight or Obesity.” Journal of obesity vol. 2018 2837367. 26 Dec. 2018, doi:10.1155/2018/2837367
  2. Strychar, Irene. “Diet in the management of weight loss.” CMAJ : Canadian Medical Association journal = journal de l’Associationmedicalecanadienne vol. 174,1 (2006): 56-63. doi:10.1503/cmaj.045037
  3. Finer, Nicholas. “Low‐Calorie Diets and Sustained Weight Loss.” Wiley Online Library, John Wiley & Sons, Ltd, 17 Sept. 2012,
  4. Noakes, Manny et al. “Meal replacements are as effective as structured weight-loss diets for treating obesity in adults with features of metabolic syndrome.” The Journal of nutrition vol. 134,8 (2004): 1894-9. doi:10.1093/jn/134.8.1894
  5. Truby, Helen et al. “Randomised controlled trial of four commercial weight loss programmes in the UK: initial findings from the BBC “diet trials”.” BMJ (Clinical research ed.) vol. 332,7553 (2006): 1309-14. doi:10.1136/bmj.38833.411204.80
  6. Huerta, S et al. “Feasibility of a partial meal replacement plan for weight loss in low-income patients.” International journal of obesity and related metabolic disorders : journal of the International Association for the Study of Obesity vol. 28,12 (2004): 1575-9. doi:10.1038/sj.ijo.0802792
  7. Weigle, David S et al. “A high-protein diet induces sustained reductions in appetite, ad libitum caloric intake, and body weight despite compensatory changes in diurnal plasma leptin and ghrelin concentrations.” The American journal of clinical nutrition vol. 82,1 (2005): 41-8. doi:10.1093/ajcn.82.1.41
  8. Heymsfield, SB. “Weight Management Using a Meal Replacement Strategy: Meta and Pooling Analysis from Six Studies.” Database of Abstracts of Reviews of Effects (DARE): Quality-Assessed Reviews [Internet]., U.S. National Library of Medicine, 1 Jan. 1970,
  9. Champagne, Catherine M et al. “Dietary intakes associated with successful weight loss and maintenance during the Weight Loss Maintenance trial.” Journal of the American Dietetic Association vol. 111,12 (2011): 1826-35. doi:10.1016/j.jada.2011.09.014
  10. Institute of Medicine (US) Subcommittee on Military Weight Management. “Weight-Loss and Maintenance Strategies.” Weight Management: State of the Science and Opportunities for Military Programs., U.S. National Library of Medicine, 1 Jan. 1970,
  11. Protein from Meat or Vegetable Sources in Meals Matched for Fiber Content has Similar Effects on Subjective Appetite Sensations and Energy Intake—A Randomized Acute Cross-Over Meal Test Study
  12. Milk supplementation facilitates appetite control in obese women during weight loss: a randomised, single-blind, placebo-controlled trial
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Garima Singh
Garima SinghMSc (Nutrition), DNHE, DDHN
Garima Singh is a certified nutritionist and dietitian with over 7 years of experience. She provides both in-office and virtual consultations and works with individuals, groups, offices, and schools. She has a passion for cooking foods in a way to make them healthy as well as palatable.

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Priyanka Sadhukhan
Priyanka SadhukhanNutritionist, CDE
Priyanka is a nutritionist and a Certified Diabetes Educator. She has over 8 years of experience in nutrition and dietetics with a strong research background. She is passionate about science and how it can be applied to one’s daily lifestyle.

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Ravi Teja Tadimalla
Ravi Teja TadimallaSenior Editor
Ravi Teja Tadimalla is a senior editor and a published author. He has been in the digital media field for over eight years. He graduated from SRM University, Chennai, and has a Professional Certificate in Food, Nutrition & Research from Wageningen University.

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Sindhu Koganti
Sindhu KogantiSenior Health & Wellness Writer
Sindhu Koganti is a Certified Health and Nutrition Life Coach and has over 6 years of experience in writing on health and wellness topics. She has a bachelor’s degree in biotechnology from Acharya Nagarjuna University, Guntur, and a diploma in nutrition from Fab Academy.

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