Weight loss isn’t just a fitness goal. It’s an entire industry filled with a multitude of products, exercise programs, and diets that all promise the same results. This explains why there’s so much confusion about how to actually lose weight. How many calories should you consume? Should you do cardio or strength training? What supplements and powders should you take?
Amidst all the conflicting information, it’s well-known that some diets are better than others in terms of long-term, sustainable, and healthy weight loss. But that same diet may not work for everyone, depending on dietary restrictions, food allergies, wellness goals, pre-existing health conditions, and other factors.
To help you decide between the best and worst diets for weight loss, here’s what actual dietitians and doctors have to say.
#1 The Mediterranean Diet
What is the Mediterranean diet?
The Mediterranean diet is the #1 best overall diet ranked by U.S. News. It’s known for being high in healthy fats like olive oil and fish. Nothing is off-limits on this diet, though some foods like eggs, poultry, dairy, red meat, and processed foods are eaten in moderation to keep saturated fat low.
Is the Mediterranean diet effective for weight loss?
Because the diet is rich in fruits, vegetables, whole grains, legumes, and nuts, the calorie distribution naturally leans toward healthier foods. This can create the caloric deficit needed for weight loss. The Mediterranean diet is not a fad diet, but rather a shift to a healthy lifestyle. It’s named after the Mediterranean population, which tends to have fewer deaths related to heart disease.
Do experts recommend the Mediterranean diet for weight loss?
The American Heart Association recommends the Mediterranean diet as a heart-healthy diet, but it can also aid weight loss. Being non-restrictive, the Mediterranean diet has the psychological benefit of disrupting the vicious starve-binge cycles perpetuated by diet culture, which tends to promote restrictive, unsustainable diets that inevitably lead to failure.
“An ‘eat less’ mindset can set us up for a cycle of guilt when unfair expectations are not met due to the biological consequences of food restrictions, such as increased cravings,” says Rachel Fine, RD, of diets with a long list of non-compliant foods. “A Mediterranean-style diet can help one build sustainable habits using a balanced and inclusive approach to eating, which can further help one achieve the weight goals they are aiming for.” 2
#2 A Plant-Based Diet
What is a plant-based diet?
A plant-based diet is much like a vegan diet with one major difference: It emphasizes whole, unprocessed plants, so processed vegan foods aren’t encouraged. The foods consumed on a plant-based diet are predominantly fruits, vegetables, nuts, seeds, grains, legumes, and soy protein.
Is a plant-based diet effective for weight loss?
Because a plant-based diet is associated with lower BMI, it’s no surprise that it’s effective for weight loss. Research has shown that a plant-based diet is an effective treatment for obesity.
One study even found that following two simple rules—eliminating animal products and reducing oils—encourages steady, long-term weight loss without restricting calories or exercising.
Do experts recommend a plant-based diet for weight loss?
Monisha Bhanote, MD, recommends a plant-based diet for weight loss as well as its other benefits: lower blood pressure, blood sugar, cholesterol, and risk of chronic diseases.
“One of the reasons a plant-based diet can help with weight loss is because this diet is packed with fiber. Fiber can help fill you up without adding extra calories,” says Dr. Bhanote. “Removing animal products, such as meat, dairy, and eggs, also removes a significant amount of fat from your diet.” 3
#3 The Engine 2 Diet
What is the Engine 2 diet?
The Engine 2 Diet takes a plant-based lifestyle to the next level. In addition to eliminating animal products, the diet restricts oils, processed foods, added sugars, and added salt. Followers stick to whole foods like grains, legumes, fruits, vegetables, nuts, seeds, tofu, and tempeh.
Is the Engine 2 diet effective for weight loss?
The Engine 2 diet is more restrictive than a traditional vegan diet, but if weight loss is your goal, this diet gets the job done in a healthy way. It’s low in fat, yet rich in fiber, vitamins, and minerals, according to U.S. News.
Do experts recommend the Engine 2 diet for weight loss?
One of the main reasons why the Engine 2 diet is effective for weight loss is that it’s high in fiber. Increasing your fiber content to at least 30 grams per day can help with weight loss, according to an Annals of Internal Medicine study.
According to Hillary Pride, RD, “The heavy focus on fruits, vegetables, legumes, and whole grains of the plant-based Engine 2 Diet means you will be consuming plenty of fiber, which has been shown to increase satiety and promote weight maintenance.” 4
#4 A Flexitarian Diet
What is a flexitarian diet?
If you’re hesitant to go full vegan but still want to dip your toes in the trend, consider a flexitarian diet. It’s exactly what it sounds like: mostly vegetarian but with the flexibility of consuming animal products when desired. Because the diet is so flexible, there are no set rules, restrictions, or must-eat foods. Much like the Mediterranean diet, a flexitarian diet encourages consuming foods in moderation with nothing being strictly off-limits.
Is a flexitarian diet effective for weight loss?
A fully vegan diet has been shown to aid weight loss, and a flexitarian diet has many of the same properties. In fact, research indicates that a flexitarian diet has health benefits related to body weight, metabolic health, blood pressure, and reduced risk of diabetes.
Do experts recommend a flexitarian diet for weight loss?
Being flexible with your diet prevents the feeling of failure and minimizes the feeling of deprivation from foods you love. “Physical, mental, and emotional satisfaction are key on a weight-loss diet so that the approach can be sustainable and help someone reach their goal in a sane and healthy manner,” says Jessica Cording, RD.
According to Cording, a flexitarian diet has the added benefit of encouraging weight loss while also allowing the occasional consumption of foods that would normally be restricted. This can be the difference between success and failure and makes someone more likely to stick to their weight management regimen long-term. 5
#5 The Ornish Diet
What is the Ornish diet?
The Ornish diet has been around for a long time, so its popularity has been buried by newer diets. However, modern-day dieters shouldn’t sleep on this way of eating because it grants you the power to eat unlimited amounts of compliant food groups. These buffet-style foods include fruits, vegetables, grains, and legumes. It’s a low-fat diet, so animal products high in fat, such as meat and dairy, are eaten in moderation.
Is the Ornish diet effective for weight loss?
The Ornish diet has always been categorized as a heart-healthy diet. It not only reduces the risk of heart disease, but it can actually reverse heart disease through diet and lifestyle. This way of eating also lowers blood pressure and cholesterol levels.
In terms of weight loss, the Ornish diet can be just as effective as all its other health benefits. Unlike low-carb diets, the Ornish diet is high in carbs. However, complex carbohydrates are the good kind of carbs, and they don’t inherently cause weight gain like processed carbs because they’re higher in digestion-slowing fiber.
Do experts recommend the Ornish diet for weight loss?
The Ornish diet is recommended to people for a variety of benefits, including sustainable weight loss. “The Ornish Diet can encourage weight loss since it shuns most processed foods and encourages whole, unprocessed foods, lots of high-quality proteins and fiber, which can leave people feeling full on less energy and ultimately lead to weight reduction,” says Monica Auslander Moreno, RD.
“It also encourages exercise and stress management, which can assist with weight loss. Unlike other diets, it doesn’t allow for rampant access to full-fat foods. Portions of healthy fats (nuts, avocado, olive oil, etc.) are explicitly detailed to avoid inadvertent high energy intakes even from healthy fats,” Moreno explains.