There are so many diets out there but not all of them are effective. Some of them are even harmful to our health. To find an effective and healthy method that will show you results in 1 month, we recommend you read this article.

Bright Side has uncovered 8 diets that have been proven effective scientifically. We’ve outlined their key rules and learned about their possible side effects.

7. A cyclical diet

The cyclical diet has nothing in common with other diets that require we suddenly stop consuming enough calories for a long period of time. On the contrary, people who have invented this diet claim that such methods shock our body, causing it to save energy and slow down our metabolism.

The standard format for a cyclical diet is 5-6 days of low-carb dieting and 1-2 days of high-carb eating. Australian scientists think that long, restrictive diets lead to adaptive thermogenesis. That means the body slows down all processes to survive while it starves. A cyclical diet lets you avoid the process of thermogenesis and your body continues to actively burn calories. The 2-week split is the most suitable. You can also try this option: from Monday till Wednesday, you have a strict diet with the regular amount of calories decreased by 30-40%; and from Thursday till Saturday, you’ll have “relaxing” days when the amount of calories increases by the same percentage. Sunday is the transition day.

Active strength and cardio workouts when the level of glucose is extremely low are prohibited for people who suffer from heart disease. This diet isn’t recommended to people who have kidney, liver, or digestive issues.

6. The Perricone diet

Dr. Nicholas Perricone is an American nutritionist and dermatologist. His diet can help you get fit and improve your skin thanks to fish fats that slow down aging.

You’re allowed to eat big amounts of fish, protein, fruit, and vegetables while on this diet. You have to exclude products like sauces, sweets, alcohol, and pastries. It’s crucial to consume the allowed products in a certain order. First, you eat food containing protein, then you eat fiber, and then foods containing carbs (fruits). This order helps to slow down the process of sugar absorption which contributes to fat deposition. You can try this method for 3 days and if you like it, you can prolong it for 1 month.

There are no contraindications.

5. The Paleolithic diet

This diet is also called the Paleo diet or the stone-age diet. It was designed by American nutritionist Loren Cordain. It requires the consumption of foods that were presumed to have been available to or consumed by humans during the Paleolithic era. As we remember learning in school, they hunted and collected berries and plants.

If you follow this diet, you have to focus on non-processed meat, vegetables, fruits, nuts, honey, berries, mushrooms, and fish. You should avoid eating any processed foods like dairy products, grains, sugar, salt, legumes, sweets, and so on. According to Cordian, these products cause health problems as they contradict the genetic structure of human beings. There’s a study that proves the paleolithic diet really helps with weight loss.

If you stop consuming dairy products, grains, and legumes, this may result in calcium, iron, and magnesium deficiency. A great amount of meat and saturated fats may cause cardiovascular system problems. The diet is quite controversial, so it’s recommended to follow a short-term paleolithic diet only.

4. Tim Ferriss’ diet

The author claims that this diet can help you lose up to 22 lb in 1 month. These are not just empty promises: Tim used his own method to get fit. The program consists of 4 simple rules.

Here are Ferriss’ recommendations: First, avoid carbs such as bread, rice, potatoes, and fried products. Second, eat the same few meals. There are 3 groups: protein, legumes, and vegetables. For breakfast, eat eggs with legumes and vegetables, for lunch, eat baked beef with legumes and spinach, and for dinner, have some boiled chicken breast with beans and asparagus. Third, don’t drink calories like soda, alcohol, packed juice, sweet tea, or coffee. Fourth, take one day off per week when you can eat your favorite snacks like fast food, sweets, and so on. This trick helps you fool your body so that it doesn’t slow down your metabolism and continues burning fat.

There are no contraindications.

3. The Atkins diet

This high-protein, low-carb diet was developed by cardiologist Robert Atkins.

If you follow this diet, you’ll have to reduce the number of carbs you consume and increase the amount of protein. The diet allows eggs, chicken without the skin, low-fat fish and seafood, low-fat dairy products, hard cheese, and tofu. In the beginning, you’re not allowed to consume fruit, sugar, legumes, grains, nuts, pasta, sweet pastries, or alcohol; but after the induction is over, you may slowly add back some of these products. You won’t starve since you can eat as many protein-containing foods as you want. All in all, because of the carb deficiency, your body has to pull the energy out from your fat reserves.

Be patient and slow while starting this diet: it’s not a balanced one. Since you’ll have a deficiency of carbs, this can lead to headaches, fatigue, dizziness, and constipation. You have to consume missing microelements with vitamins. What’s more, the diet is prohibited if you suffer from certain diseases (e.g. diabetes). So before you start following this diet, you should consult your doctor.

2. The Ornish diet

Dean Ornish is a Clinical Professor of Medicine at the University of California, a cardiologist, and Bill Clinton’s personal physician consultant. His diet is low-fat and high-carb. It helps to lose weight, has a great impact on the cardiovascular system, and reduces blood pressure and the level of cholesterol.

According to this method, your menu should consist of no more than 10% fat. Ornish’s ratio of carbs, protein, and fats is rather controversial: there should be 10% fat, 15% to 20% protein, and 70% to 75% good carbs. You should avoid consuming alcohol, all sources of caffeine, avocado, butter, nuts, and sweets. You’re allowed to eat beans, legumes, grains, fruit, and vegetables. It’s also recommended to reduce the amount of meat you eat. If you want to eat meat, it’s better to choose lean chicken meat.

The medical community approves the Ornish diet and confirms all the positive effects it has on the body. The effectiveness has also been proven by Ornish’s personal research published in the Journal of the American Medical Association and by Stanford University scientists’ research conducted in 2007.

Similarly to many other diets, this method has been criticized. For example, if you fail to design and follow a proper menu, a deficiency of protein, vitamin B12, and other useful substances can occur. Nevertheless, the diet has existed for more than 40 years and proves that it’s useful and healthy.

1. The Volumetrics diet

This diet was developed by Barbara Rolls, a professor of nutritional sciences at Pennsylvania State University. The main idea of her diet is that you shouldn’t care about the amount of food you eat, you can eat as much as you want.

According to Rolls, awareness of the energy density of food, which is the number of calories in a specific amount of food, is the key to achieving healthy, long-term weight loss. You don’t have to avoid eating unhealthy food. The thing is, you have to eat a low-calorie product before you eat a high-calorie meal. Such low-calorie foods are: vegetables, soups, smoothies, and so on. Thus, you eliminate the feelings of hunger and feel full. Different studies prove that the system works and highlight that reducing the density of your menu helps people lose weight, stay fit, and teaches them to control their hunger.

There are no contraindications.

Bonus: The egg diet

Egg diets are really useful if you follow all the necessary rules. Eggs contain protein which is extremely important for our skin, nails, and hair. There are 2 types of effective egg diets: a long-term and a short-term one. But the short-term diet has too many contraindications, so we recommend to follow the long-term egg diet instead.

If you want to try a long-term diet, it’ll last for 1 or 2 weeks. Your breakfast will consist of 2 eggs and 1 grapefruit, your lunch will consist of an egg, a grapefruit or a salad without dressing, and for a supper, you’ll have 1 egg and 3.5 oz of low-fat meat or fish with vegetables. Don’t salt your food — sprinkle some lemon juice on your dish instead.

This diet is quite balanced. As long as you don’t avoid eating any of these products, your body won’t suffer from any deficiency. You just have to make sure you’re not allergic to grapefruit. It’s also recommended to reduce the number of workouts per week as not to exhaust your body.

Of course, it’s important to go to the gym to let your body recover and get fit while the extra pounds disappear. So if you follow a diet, don’t forget about exercise!

Have you tried any of these diets? Share your experience and results to inspire others!