If a person is interested in weight loss, he or she might hear numerous weight loss diets. 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 6 most popular weight loss diets and the science behind them.
1. Low-Carb Diets
This kind of diet has been popular for decades, especially for weight loss. Though there are several types of low-carb diets, all involve limiting carb intake to 20–150 grams daily. The primary aim of the diet is to force your body to use more fats for fuel instead of using carbs as a main source of energy.
How it works:
A low-carb diet emphasizes unlimited amounts of protein and fat while severely limiting your carbohydrate intake. When carbohydrate intake is very low, fatty acids enter your bloodstream and are transported to your liver, where some of them are converted into ketone bodies. Your body can then use fatty acids and ketone bodies as its primary source of energy without carbohydrates.
Numerous studies have shown that low-carb diets are very helpful for weight loss, especially for overweight and obese people. They seem to be very effective in reducing dangerous belly fat that can get stuck around your organs.
People who practice very low-carb diets often reach a state called ketosis. Many studies have noted that ketogenic diets result in more than twice the weight loss compared to low-fat, calorie-restricted diets.
Low-carb diets tend to reduce your appetite, making you feel less hungry and leading to an automatic reduction in calorie intake. In addition, a low-carb diet may benefit many major disease risk factors such as blood triglycerides, cholesterol levels, blood sugar levels, insulin levels and blood pressure.
Low-carb diets are not for everyone. Some people feel great on the diet, while others feel miserable. Some people may experience an increase in “bad” LDL cholesterol. In extremely rare cases, very low-carbohydrate diets can lead to a serious condition called non-diabetic ketoacidosis. This condition appears to be more common in lactating women and can be fatal if left untreated.
However, low-carbohydrate diets are safe for most people.
2. The Paleo Diet
The paleo diet claims you should eat the same foods your hunter-gatherer ancestors ate prior to the development of agriculture. The theory suggests that most modern diseases are associated with the Western diet and the consumption of grains, dairy products and processed foods. While it is debatable whether this diet actually provides the same foods your ancestors ate, it has been linked to several impressive health benefits.
How it works:
The paleo diet emphasizes whole foods, lean proteins, vegetables, fruits, nuts and seeds while discouraging processed foods, sugar, dairy products and grains. Some more flexible versions of the paleo diet also allow dairy products such as cheese and butter, and tubers such as potatoes and sweet potatoes.
Several studies have shown that the Paleo diet can lead to significant weight loss and waist size reduction. In the studies, paleo dieters automatically reduced carbohydrates, increased protein and ate 300-900 fewer calories per day.
This diet appears to be effective in reducing risk factors for heart disease, such as cholesterol, blood sugar, blood triglycerides and blood pressure.
The paleo diet eliminates whole grains, legumes and dairy products, all of which are healthy and nutritious.
3. The Atkins Diet
The Atkins diet is the most famous low-carb weight loss diet. Its proponents insist that you can lose weight by eating as much protein and fat as possible, as long as you avoid carbohydrates. The main reason low-carb diets are so effective for weight loss is that they reduce your appetite. This allows you to eat fewer calories without having to think about it.
How it works:
The Atkins diet is divided into four phases. It begins with an induction phase in which you eat less than 20 grams of carbohydrates per day for two weeks. Other phases include slowly reintroducing healthy carbohydrates into your diet as you approach your goal weight.
Extensive research has been conducted on the Atkins diet and found that it can lead to faster weight loss than low-fat diets. Other studies point to low-carb diets as being helpful for weight loss. They are particularly successful in reducing belly fat, the most dangerous fat that resides in your abdominal cavity.
Numerous studies have shown that low-carb diets, such as the Atkins diet, can reduce risk factors for many diseases, including blood triglycerides, cholesterol, blood sugar, insulin and blood pressure. Low-carb diets also improve blood sugar, “good” HDL cholesterol, triglycerides and other health indicators better than other weight loss diets.
As with other very low-carb diets, the Atkins diet is safe and healthy for most people, but can cause problems in rare cases.
4. Intermittent Fasting
Intermittent fasting allows your body to cycle between fasting and eating. Rather than restricting the foods you eat, it controls when you eat them. Therefore, it can be seen as a dietary pattern rather than a diet.
The most popular methods of intermittent fasting are:
- The 16/8 method: Involves skipping breakfast and restricting your daily eating period to eight hours, subsequently fasting for the remaining 16 hours of the day.
- The eat-stop-eat method: Involves 24-hour fasts once or twice per week on non-consecutive days.
- The 5:2 diet: On two non-consecutive days of the week, you restrict your intake to 500–600 calories. You do not restrict intake on the five remaining days.
How it works:
Intermittent fasting is often used for weight loss because it leads to relatively easy calorie restriction. It allows you to eat fewer calories overall – as long as you don’t overcompensate by eating more during the eating periods.
Intermittent fasting is usually very successful for weight loss. It has been shown to result in weight loss of 3-8% over a period of 3-24 weeks, which is a big advantage compared to most weight loss diets. In addition to causing less muscle loss than standard calorie restriction, it may also increase your metabolic rate by 3.6-14% in the short term.
Intermittent fasting reduces markers of inflammation, cholesterol levels, blood triglycerides and blood glucose levels. In addition, intermittent fasting has been associated with increased human growth hormone (HGH) levels, improved insulin sensitivity, improved cellular repair and altered gene expression.
Animal studies also suggest that it may help new brain cell growth, extend life span, and prevent Alzheimer’s disease and cancer.
Although intermittent fasting is safe for well-nourished and healthy people, it is not for everyone. Some studies point out that it is not as beneficial for women as it is for men. In addition, some people should avoid fasting, including those who are sensitive to drops in blood sugar levels, pregnant women, breastfeeding mothers, adolescents, children, and people who are malnourished, underweight, or nutritionally deficient.
The Bottom Line
There is no perfect diet for weight loss. Different diets work for different people, and you should choose one that suits your lifestyle and tastes. The best diet for you is the one that you can stick to for a long time.