There are many weight loss diets out there. Some focus on reducing your appetite, while others restrict calories, carbs, or fat. Since all of them claim to be superior, it can be hard to know which ones are worth trying. The truth is that no one diet is best for everyone — and what works for you may not work for someone else.
This article reviews the 2 most popular weight loss diets and the science behind them.
1. The Paleo Diet
The paleo diet claims that you should eat the same foods that your hunter-gatherer ancestors ate before agriculture developed.
The theory is that most modern diseases can be linked to the Western diet and the consumption of grains, dairy, and processed foods.
While it’s debatable whether this diet really provides the same foods your ancestors ate, it is linked to several impressive health benefits.
How it works: The paleo diet emphasizes whole foods, lean protein, vegetables, fruits, nuts, and seeds, while discouraging processed foods, sugar, dairy, and grains.
Some more flexible versions of the paleo diet also allow for dairy like cheese and butter, as well as tubers like potatoes and sweet potatoes.
Weight loss: Several studies have shown that the paleo diet can lead to significant weight loss and reduced waist size (1Trusted Source, 2Trusted Source, 3Trusted Source, 4Trusted Source).
In studies, paleo dieters automatically eat much fewer carbs, more protein, and 300–900 fewer calories per day (1Trusted Source, 2Trusted Source, 3Trusted Source, 4Trusted Source).
Other benefits: The diet seems effective at reducing risk factors for heart disease, such as cholesterol, blood sugar, blood triglycerides, and blood pressure (5Trusted Source, 6Trusted Source, 7Trusted Source).
The downside: The paleo diet eliminates whole grains, legumes, and dairy, which are healthy and nutritious.
2. The Vegan Diet
The vegan diet restricts all animal products for ethical, environmental, or health reasons.
Veganism is also associated with resistance to animal exploitation and cruelty.
How it works: Veganism is the strictest form of vegetarianism.
In addition to eliminating meat, it eliminates dairy, eggs, and animal-derived products, such as gelatin, honey, albumin, whey, casein, and some forms of vitamin D3.
Weight loss: A vegan diet seems to be very effective at helping people lose weight — often without counting calories — because its very low fat and high fiber content may make you feel fuller for longer.
Vegan diets are consistently linked to lower body weight and body mass index (BMI) compared to other diets (8Trusted Source, 9Trusted Source, 10Trusted Source, 11Trusted Source, 12Trusted Source).
One 18-week study showed that people on a vegan diet lost 9.3 pounds (4.2 kg) more than those on a control diet. The vegan group was allowed to eat until fullness, but the control group had to restrict calories (13Trusted Source).
However, calorie for calorie, vegan diets are not more effective for weight loss than other diets (14Trusted Source).
Weight loss on vegan diets is primarily associated with reduced calorie intake.
Other benefits: Plant-based diets are linked to a reduced risk of heart disease, type 2 diabetes, and premature death (15Trusted Source, 16Trusted Source, 17Trusted Source, 18Trusted Source, 19Trusted Source).
Limiting processed meat may also reduce your risk of Alzheimer’s disease and dying from heart disease or cancer (20Trusted Source, 21Trusted Source, 22Trusted Source, 23Trusted Source, 24Trusted Source).
The downside: Because vegan diets eliminate animal foods completely, they may be low in several nutrients, including vitamin B12, vitamin D, iodine, iron, calcium, zinc, and omega-3 fatty acids (25Trusted Source, 26Trusted Source, 27Trusted Source, 28Trusted Source, 29Trusted Source).
The Source https://www.healthline.com/nutrition/9-weight-loss-diets-reviewed#section2