The 9 Best Diets for Weight Loss – SI Showcase

The 9 Best Diets for Weight Loss – SI Showcase

Best Weight Loss Diets_hero

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The concept of losing weight is simple—run a caloric energy deficit over time and you’ll eventually shed pounds.

But the key to weight loss isn’t finding a diet that works in theory. It’s finding an achievable diet plan based on your lifestyle and, to some degree, your psychological, genetic and metabolic make up.

Are you a Type A personality who prefers rule-based plans to flexible ones? Where do you tend to gain weight? Can your work-life balance handle food logging? What’s your medical history?

These factors (and more) matter when it comes to choosing an effective weight loss diet—one you can follow through on long-term. They also determine the rate of your fat burn. Is fast weight loss realistic for you? Is it the healthiest route?

This article introduces the best diet for weight loss in various categories, including the best diet for PCOS weight loss and the best diabetic diet for weight loss.

This content is meant to be informative, but should not be taken as medical advice. It is not intended for use as diagnosis, prevention or treatment of health problems. Always speak with your doctor before starting any new supplement or exercise regimen.

Our Picks for the Best Diet for Weight Loss:

  • Best Overall Weight Loss Diet: Nutrisystem
  • Best Psychology-Based Weight Loss Diet: Noom
  • Best Fasting Weight Loss Diet: DoFasting
  • Best Weight Loss Diet for Community Support: WW
  • Best Weight Loss Diet for Diabetes: Mediterranean Diet
  • Best Diet for PCOS Weight Loss: Mayo Clinic Diet
  • Best Weight Loss Diet for Seniors: DASH Diet
  • Best (Mostly) Vegetarian Weight Loss Diet: Flexitarian Diet
  • Best Weight Loss Diet for Pre-Made Food: Jenny Craig
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  • How it works for weight loss: Pick a meal plan that suits your taste and budget, and get fully prepared meals delivered to your doorstep. Each plan comes with an on-demand weight loss coach to guide your weight loss journey.
  • Key foods: There are over 130 meal options. They are mostly low-calorie, low-sugar, high-protein meals designed to promote fast weight loss.
  • Downsides: This may be a less eco-friendly option than cooking for yourself. The meal packaging may generate more waste than usual.

Nutrisystem benefits people who want to eat healthier, but don’t have time to cook meals everyday. With Nutrisystem, you can follow a healthy diet with little effort.

This diet lets you pick the best meal plan for your needs and delivers it right to your door. It includes meals designed by dietitians for women’s weight loss, men, couples and women over 55. You can also choose a plan based on your dietary restrictions and medical history, like the vegetarian or diabetes option.

Ultimately, Nutrisystem is a convenient way to follow a healthy diet plan. It proves you can lose weight without the hassle of daily calorie counting, food logs or meal-prepping.


  • No calorie counting
  • Takes the guesswork out of portion sizes
  • Easy-to-follow
  • Seven-day money back guarantee


  • No vegan or nut-free meal plans
  • Expensive compared to other diets on our list
  • Doesn’t allow you to cook your own recipes
  • How it works for weight loss: Noom combines psychology, human coaching and technology to create a customized diet plan. Integrate it into your everyday routine for long-term weight management.
  • Key foods: Noom focuses on less calorie-dense foods that help you feel full quicker. Your food options are plentiful: fruits, veggies, whole grains, red meats, poultry, fish and low-fat dairy products.
  • Downsides: This diet plan may be hard for ultra busy people to keep up with. It requires you to log your food choices, physical activity, water intake and body weight every day.

Noom is about making behavioral changes that promote life-long healthy eating habits. It pinpoints the reasons you have struggled with dieting, and provides a personalized plan to help you overcome them.

After downloading the Noom app, you’ll complete a 15-minute questionnaire about your weight loss goals, health status and demographics (age, sex, gender etc.). It then provides reasonable daily goals to guide your diet, plus tips to make healthier lifestyle changes across the board.

You can also take part in daily lessons. They aim to help you find the triggers behind your unhealthy eating habits, uncover emotional ties to food and combat psychological barriers that keep you from maintaining a healthy diet long-term.


  • 24/7 access to virtual health coaches via the mobile app
  • Addresses the psychology of eating to improve your weight management
  • Provides daily encouragement as you work toward you weight loss goal
  • Curbs overeating


  • Expensive compared to other weight loss apps
  • Only accessible with a smartphone or tablet
  • Requires daily logs some may find time-consuming
  • How it works for weight loss: DoFasting provides a custom-fit intermittent fasting program and expert tools to guide you. It includes workouts, meal plans, a progress tracker and over 5,000 recipes created by professional nutritionists.
  • Key foods: DoFasting accommodates a wide range of food preferences. Instead of restricting foods, it focuses on optimal fasting periods and eating windows. It aims to help you consume fewer calories while still eating foods you like.
  • Downsides: DoFasting requires adherence to a strict fasting schedule. It may not be the best choice for people with unpredictable work and personal schedules.

Scientific evidence suggests that intermittent fasting is one of the best diets for fast weight loss. A recent study found that intermittent fasting may also be helpful for the prevention and management of chronic diseases, such as Type 2 diabetes and heart disease.

DoFasting is an app-based weight loss diet that provides a trackable way to try fasting. The app tailors a fasting schedule to your lifestyle and weight loss goals based on your completed questionnaire. Adjust your plan to try different types of fasting, like 24-hour, 16-hour and 14-hour fasts.

DoFasting promotes additional health benefits outside of weight loss, like improved heart health and enhanced mental function, according to its creators. The goal is to reach a healthy weight and make healthy lifestyle changes to keep the weight off.


  • Lose weight fast while eating your favorite foods
  • Provides at-home workout ideas suitable for all ages and skill levels
  • Expert-recommended recipes you can make in under 10 minutes


  • Requires adherence to a strict fasting schedule
  • Requires a subscription plan that may be off putting to commitment-phobes
WW tracking
  • How it works for weight loss: WW assigns a PersonalPoints™ Budget to members based on their lifestyle and food preferences. It aims to help you eat fewer calories without limiting your food options.
  • Key foods: WW doesn’t restrict what foods you can eat. Instead, all foods have a Point value. You can eat whatever foods you want as long as you stay within your daily and weekly Point budget.
  • Downsides: WW requires you to log what you eat and keep track of your food Points throughout the day. It may be overwhelming for people with hectic schedules.

Formerly known as WeightWatchers, WW is ideal for people who struggle with food cravings and portion control. It allows you to eat whatever you want as long as you don’t go over your allotted points.

WW is an excellent diet for people who value community support. Membership grants you access to an exclusive digital community you can lean on for tips, motivation and emotional support. You can also have a personal coach and receive one-on-one coaching sessions. Check-in weekly to review your progress and set goals for the next week.

Keeping up with your food Points is easy using the WW app. It allows you to scan a food item’s barcode while you shop so you can see its Point value. You also get 12,000 recipes, weekly 30-minute group workshops and on-demand workout videos for all levels.


  • Eat whatever foods you want
  • Access millions of community members for tips and motivation
  • 24/7 access to a personal coach
  • Achieve healthy lifestyle changes, like drinking more water and getting more sleep


  • You have to track every meal and snack

Best Weight Loss Diet for Diabetes: Mediterranean Diet

Mediterranean Diet_Source iStock
  • How it works for weight loss: The Mediterranean diet is all about replacing unhealthy food choices with healthy foods from every food group. For example, red meat is avoided and replaced with lean protein sources like fish. It’s based on the eating habits of Mediterranean countries, like Greece, Spain, Italy and Morocco.
  • Key foods: Your food options are flexible with a Mediterranean diet. Use olive oil as your primary source of fat and eat lots of plant-based foods and whole grains. Saturated fats should be replaced with unsaturated fats (healthy fats). Eat fish, poultry and lean meats. Limit red meats. Eat fruit as dessert. Add low-fat dairy products like yogurt.
  • Downsides: This diet requires you to cook your own meals, so it might not be the best weight loss diet for people with busy schedules or without cooking skills.

The Mediterranean diet offers many health benefits alongside weight loss. According to a recent study published by the Journal of Internal Medicine, it may reduce the risk of Type 2 diabetes and cancer. It may also help lower high blood pressure and high cholesterol. The American Heart Association endorses it as a heart-healthy diet.

This is a great option for people who already follow a plant-based diet or want to start. No food is off-limits with this diet, not even processed foods. Nonetheless, highly processed foods and high-fat foods should be avoided.

We rank the Mediterranean diet as the best diabetic diet for weight loss because it strictly limits sweets and high-sugar foods, recommending fruit and nonfat yogurt in their place. It also emphasizes daily servings of low and zero-sugar foods like vegetables, brown rice, legumes, lentils and lean protein. These foods are relatively low on the glycemic index (GI) scale and don’t cause significant spikes in blood sugar levels.


  • Inexpensive; no subscription or membership costs
  • Flexible food options
  • Promotes long-term health benefits
  • Accommodates a diabetic diet


  • Requires you to cook your own meals
  • Self-guided; doesn’t include coaching or community support

Best Weight Loss Diet for PCOS: Mayo Clinic Diet

Mayo Clinic Diet_Source Mayo Clinic
  • How it works for weight loss: Follow the Mayo Clinic Healthy Weight Pyramid to eat foods that are filling but low in calories. It focuses on portion sizes so you consume fewer calories during meals and when snacking.
  • Key foods: Your choice of food is flexible. The diet encourages unlimited amounts of fruits and veggies and restricts the consumption of sweets to 75 calories a day. Whole grains, fish, lean protein (nuts) and healthy fats are also recommended.
  • Downsides: Since the natural sugar in fruit affects your intake of carbohydrates, this diet may temporarily raise your blood sugar, especially if you eat a lot of fruit.

The Mayo Clinic Diet is designed to help you lose six to ten pounds in the first two weeks, making it one of the best diets for fast weight loss. If you have the will power, repeat the two-week process and potentially drop 12 to 20 pounds in one month. However, it is very restrictive. Doubling it won’t be easy if you’re not motivated.

The Mayo Clinic Diet is broken into two phases as follows:

Phase 1 is called the “lose it” phase. You learn how to break five unhealthy habits and add ten healthy habits to your everyday routine. You can’t eat any sugar that doesn’t come from fruit, nor drink alcohol or eat out. You can’t even eat while watching TV.

Phase 2 is the “live it” phase. It transitions you to a new health-conscious routine, one that prioritizes healthy eating habits and regular exercise. You come to view your food choices as preventative healthcare, instead of a short-term method of losing weight.

The Mayo Clinic Diet is a flexible weight loss diet that you can tailor to your food preferences and dietary restrictions. If you need extra guidance, choose one of the five different meal plans: the Original Mayo Clinic Diet, Higher Protein, Health Keto, Vegetarian or Mediterranean. In addition to healthy eating, participants are encouraged to do at least 30 minutes of physical activity every day.

Women with polycystic ovary syndrome (PCOS) who need to lose weight should consider this diet. We rank it as the best diet for PCOS weight loss because healthy lifestyle changes are key to treating PCOS. Healthcare providers commonly recommend that women with PCOS lose weight using a low calorie diet and moderate exercise.


  • Developed by medical professionals
  • Reduces health risks
  • Accommodates PCOS weight loss
  • Fast weight loss


  • The first two weeks of the program are very restrictive

Best for Seniors: DASH Diet

DASH Diet_Source iStock
  • How it works for weight loss: The DASH Diet follows a 28-day eating plan of guided meals and recommended workouts to help you lose weight and improve your heart health. On top of that, it provides tips for long-term weight management, like how to deal with stress and improve the quality of your sleep.
  • Key foods: DASH is similar to the Mediterranean diet. It includes fruits, vegetables, whole grains, lean meats and nuts. It limits food high in saturated fat, cholesterol and trans fat. It strictly limits sweets, sugary beverages, red meats and high-sodium foods.
  • Downsides: The DASH diet restricts certain foods, so it’s not the best option for people who want to eat cake and have their weight loss too.

DASH stands for Dietary Approaches to Stop Hypertension. As the name suggests, the program was created to help people lower their blood pressure using a healthy diet. We rank DASH as the best diet for weight loss for seniors because 70 percent of adults over 65 have high blood pressure.

The DASH eating plan emphasizes the consumption of essential nutrients like calcium, magnesium and potassium. “The ability to maintain calcium balance worsens and bone loss accelerates after 50 years of age. Your risk of fracture also increases with older age. In fact, several studies have shown that calcium combined with low daily doses of Vitamin D reduces fracture risk and increases bone density,” says Mayo Clinic Endocrinologist Dr. Robert Wermers.


  • Designed to lower blood pressure
  • Easy-to-follow 28-day eating plan
  • Good for seniors
  • Nutrient-rich foods for optimal vitamin and mineral intake


  • Strictly limits sweets and sugary beverages; sweet-tooths beware

Best (Mostly) Vegetarian Weight Loss Diet: Flexitarian Diet

Flexitarian diet
  • How it works for weight loss: Plant-based diets are low-calorie and low-fat. A diet that prioritizes eating fruits and vegetables while limiting meat is an effective way to shed body fat. It’s often recommended as a treatment for obesity.
  • Key foods: This is a mostly plant-based diet with high daily servings of fruits and vegetables, especially leafy greens. It limits meat consumption to three times a week. Your meats should be organic, free-range and/or grass-fed. Whole foods and non-meat proteins are encouraged. It strictly limits highly processed foods and sugary beverages.
  • Downsides: This diet may leave you feeling hungry. A primarily plant-based diet can significantly reduce your calorie intake. You may not feel as full as usual after meals.

Often called a semi-vegetarian diet, the Flexitarian diet is a flexible version of a vegetarian diet. Plant-based foods are emphasized, but you can still eat meat occasionally.

A Flexitarian diet may help you get rid of stubborn belly fat. According to one study, adherence to a plant-based diet was associated with lower abdominal fat.

The Flexitarian diet may also help reduce blood pressure, blood cholesterol and the risk of developing Type 2 diabetes.

If you’ve ever considered going full vegetarian, or even vegan, the Flexitarian diet is a great way to ease into those restrictive diets while also losing weight.


  • May help burn belly fat
  • Provides additional health benefits
  • Eco-friendly


  • May leave you feeling hungry
  • How it works for weight loss: Jenny Craig uses portion-controlled meals and snacks to help you eat fewer calories. You eat six small portion size meals per day, but only between the hours of 9am and 7pm.
  • Key foods: In the first stage of the diet, you can only eat Jenny Craig foods. These are meals created and sold by the program. They include common foods like lasagna, pizza, cupcakes and ice cream, made with high quality ingredients. In the second stage, participants transition to home-prepared meals, focusing on small portion sizes and a low calorie intake.
  • Downsides: The program is expensive compared to other alternatives. It might not be ideal for those on a tight budget.

Jenny Craig is a household diet name, like the Atkins diet or Paleo. Its popularity, to some extent, says a lot about its credibility as an effective weight loss diet.

A typical Jenny Craig plan allots a daily caloric intake of 1,200 (which is very low for almost all adults) to 2,300 calories, depending on your sex, age and weight loss goals. It includes intermittent fasting, with a 10-hour eating window and a 14-hour fasting period. The program also recommends 30 minutes of physical activity five days a week.

A key component of the Jenny Craig diet is the individualized support from Jenny Craig coaches. However, these coaches are not registered dietitians or health professionals. They are previous members of the program who achieved successful weight loss results.



  • Expensive
  • Some meal plans promote excessively low calorie allotments

How We Chose the Best Diets for Weight Loss

In general, we looked for diets that encourage people to consume a healthy variety of foods without demonizing or cutting out complete groups, have science-backed results, focus on actual food rather than diet products and are actually possible for people to stick to.

How to Choose the Best Weight Loss Diet for You

Choosing the best weight loss diet for you requires finding one that gels with your lifestyle and accommodates your personality. It also helps if it aligns with your food preferences. Consider your health status and budget, as well.

Ultimately, you have to set realistic expectations based on everything you know about yourself. What motivates you? Are you organized enough to keep a daily food log? How much spare time can you dedicate to your weight loss goals? Are you willing to count calories every meal? How well can you control your food cravings?

By answering these questions, you’ll be in a better position to narrow down your diet plan choices. The more honest you are with yourself, the better your chances of finding an effective weight loss plan that delivers the results you want.

Who Should Avoid Weight Loss Diets

Most weight loss diets are, effectively, just a healthier or lower-calorie way of eating, which makes them generally safe for many people. However, extreme weight loss diets intended to promote rapid weight loss come with added health risks. Consult your physician about your weight loss goals for additional guidance.

People who should avoid weight loss diets include, but aren’t limited to:

  • Individuals whose physician advises against losing weight
  • Individuals with a history of eating disorders (e.g. anorexia nervosa, bulimia nervosa)
  • Individuals with medical conditions that require specific nutrient intake or restriction

If you’re unsure if a weight loss diet is appropriate for you, talk with your doctor or a registered dietician.

Diets That Help You Burn Belly Fat

Belly fat is notoriously hard to get rid of, and there’s an evolutionary reason why. “The body preferentially sends fat to the waist so that the stored energy is near the vital organs in case they need it,” says registered dietitian Betsy Opyt, R.D.

If you’re looking for a solution to burn off stubborn belly fat, there’s good and bad news.

The good news is that burning belly fat to achieve a flatter stomach is possible, and may be enhanced by certain diets.

The bad news, however, is that there’s little conclusive scientific evidence to support the idea of targeting belly fat through dieting alone.

“It’s impossible to target belly fat specifically when you diet. But losing weight overall will help shrink your waistline; more importantly, it will help reduce the dangerous layer of visceral fat, a type of fat within the abdominal cavity that you can’t see but that heightens health risks,” says Kerry Stewart, Ed.D., director of Clinical and Research Physiology at Johns Hopkins.

In other words, burning belly fat through dieting requires that you shed total body fat in the process. Nonetheless, there are dieting strategies you can use to burn belly fat faster.

One such strategy is to focus on curbing carbs, rather than fats. When researchers at Johns Hopkins compared the effects of a low-carb diet to a low-fat diet, they found that a low-carb diet led to an average of 10 more pounds of weight loss compared to a low-fat diet. These results suggest that a low-carb diet may be one of the best ways to burn belly fat while also reducing your overall body weight.

Physical activity is another proven way to burn belly fat. “Exercise seems to work off belly fat in particular because it reduces circulating levels of insulin—which would otherwise signal the body to hang on to fat,” says Kerry Stewart, Ed.D.

This all suggests that a low-carb diet combined with regular exercise may be the best way to get rid of belly fat.


How do you detox your body to lose weight?

“Detox” is a misleading term. As long as you don’t have any sort of medically diagnosed problem with your kidneys or liver, you do not need to do any sort of detox. Your organs do the work of clearing any toxic substances from your body.

What foods help burn belly fat?

Following a low-carb diet can help you burn belly fat. Eat more vegetables, lean protein sources and fruits. Eliminate foods that are high in trans fat and carbohydrates from your diet. Avoid highly processed foods, as well.

Eat fish and non-meat protein sources instead of red meats. Always opt for unsaturated fats (healthy fats) over saturated fats. For example, use extra virgin olive oil on your salad instead of high-fat dressing. Avoid solid cooking fats like butter, lard and shortening.

What drinks help with weight loss?

Drinking only water can significantly lower your daily intake of calories, carbohydrates and sugar.

These drinks may also help with weight loss:

  • Green, black and ginger teas
  • Coffee
  • High-protein, low-calorie drinks
  • Apple Cider Vinegar (ACV) drinks
  • Fruit and vegetable juices

How long should I be on a diet?

Stick to your diet until you reach your desired healthy weight goal. Try to transition your new diet into an everyday routine of healthy, mindful eating. This will improve your weight management long-term and curb future weight gain.

Final Thoughts

Taking a personalized approach to dieting improves your weight loss results. Diet fads will come and go, but your personal character traits are more or less permanent; they will likely contribute to your weight loss more than anything else. Custom-fit your next diet to your unique self, and positive results will surely follow.

Also, take comfort in the fact that if you don’t see results right away, you are likely improving underlying aspects of your health by following a healthier diet. Don’t give up! With or without weight loss, improving your health is always a worthy cause.

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