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The best fad diets and how they work 2021

Here’s everything you need to know about the latest dieting crazes.

Every year the number of people pledging to lose weight and get more active rises, especially at New Year and during those pre-summer months. Gyms are packed to the brim and Weight Watchers’ sign-ups spike.

With this motivation of making a change, during these early months of the year, lots of us turn to fad diets to aid our weight-loss goals.

Fad diets receive a lot of bad press and have been met with skepticism by leading experts, but the quick results promised by most of them is still alluring to many, especially when you hear accounts of celebrities like Kim Kardashian, who attributes her post-baby weight loss to the Atkins diet.

With this in mind, here’s a breakdown of the rules and restrictions of the most popular fad diets. Read, compare and see if any of them might work for you.


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1. The Atkins diet

Atkins is one of the most famous diet plans out there. As a general rule it involves reducing your intake of carbohydrates in order to get the body to burn fat instead of the fuel provided by carbs. The diet has been criticised for placing no restrictions on quantities or on protein-rich and high-fat foods, although in recent years Atkins has included more guidance around portion control and healthy food choices. Atkins has been a very successful diet for many but you should do some research into it and talk to a nutritionist about the associated health risks before switching to this diet.


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2. Ketogenic Diet

This diet is all about getting your body to trigger ketosis, a state where your body has no sugar fuel to burn so it burns fat instead, thus resulting in weight loss. It is a very, very low-carb, high-fat diet plan where your daily net carb intake can’t be more than 50 grams. As a result, many people liken it to the Atkins diet. The key difference is that a ketogenic diet limits your daily protein intake to 15–25%, a restriction that the Atkins diet does not have. It’s been criticised for its recommendation that 70% of your diet should be made up of fat.


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3. Palaeolithic Diet

The paleo diet is one of the newest fads on the block, the general premise being to only eat what was available to Neanderthals from the Paleolithic era. This means eliminating processed foods, like breads and sugar, and things like dairy, grains and legumes that would have been difficult to come by before agriculture was invented. The paleo diet is not technically a low-carb diet as these mostly restrict vegetable consumption down to 15% or lower, whereas the paleo diet encourages 35–45% of your diet be made up of non-starchy vegetables. The paleo diet is one of the less criticised fads since the advice to eat fewer processed and sugary foods aligns with the mainstream conventions of a healthy diet. However it has still been criticised since it is likely that Paleolithic humans had very adaptable digestive systems and that they consumed grains, facts which undermine the whole premise of the diet.


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4. Vegan Diet

Veganism has boomed in popularity over the last couple of years. But, could a vegan diet actually help you lose weight? It is widely believed that turning to a vegan diet could help you shed pounds fast and why not? Vegans eliminate all meat and any animal byproducts from their diet. So, no cheese, milk, eggs etc. Instead they eat only plant-based produce such as vegetables, grains, nuts and fruit. If done in a healthy and balanced way, the vegan diet could be a very successful way to lose weight, however, you should steer clear of cooking oils that are high in saturated fat and remember, surviving on bread and pasta alone isn’t going to help your waistline any. The vegan diet is criticised by experts due to the lack of vitamins B12 and D found in the food, so if you do decide to #govegan, consider taking vitamin supplements to keep your red blood cell count high and your bones strong.


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5. The zone diet

The zone diet is another breed of low-carb diet that has very specific recommendations about the amount of carbs and protein that you can eat in a day. It also encourages the idea of eating five small meals (rather than three regular-sized ones) to help you feel fuller across the whole day. According to the official website you need to “eat in the zone” and “balance your plate at every meal with one third protein the size and thickness of your palm, two thirds colorful fruit and vegetable carbs, and a dash of fat”. You are also encouraged to take vitamins and omega supplements and to increase your physical fitness with exercise. All these diet and lifestyle changes are designed to put your body in “the zone” that reduces diet-induced inflammation causing weight gain, sickness and ageing. Most of the claims of this diet are unfortunately unproven and its efficacy has yet to be verified.


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6. Intermittent Fasting Diet

The latest dieting craze to take the world by storm is the Intermittent Fasting Diet. It claims that you can improve your metabolic health, lose weight and even extend your life expectancy. Plus, with there being several different ways you can attack this diet, it’s a fairly versatile plan which, with a bit of discipline, could work for everyone’s lifestyle. The idea is to fast to a routine. The 16/8 method requires fasting for 16 continuous hours each day, and dieters may eat normally for the other eight hours. The 5:2 method is where you would be required to fast for 2 days per week, whilst eating as normal on the other 5. Finally the Alternate-Day-Fasting is where you would fast every other day whilst eating normally on the days in between. The problem with this diet is that you may feel you can eat everything and anything during your can-eat schedule, which is not actually the case. You must maintain a healthy and well-balanced diet throughout to see the results you want. As this diet is still quite new on the scene, it’s not actually been proven or disproven to work long-term just yet and the drastic change in your calorie intake could actually end up slowing your metabolism down.


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7. The Alkaline Diet

This diet was created on the belief that our bodies are prone to health complaints such as arthritis, diabetes and even cancer due to the acidic fluids we are made up of. The idea of The Alkaline Diet is to replace acid-forming foods with alkaline alternatives such as lemons, watermelons, celery, limes, dates and mangoes. Foods that are considered to be acid-forming are things like eggs, meat, poultry and dairy, so, The Alkaline Diet seems to have something in common with the Vegan Diet. As all the foods recommended by this diet are good for your health, it stands to reason that this could be a great weight-loss option. As for the claims that The Alkaline Diet can help you ward off or fight cancer, there is no recorded evidence to support this.


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8.Juice Fasting

Juice Fasting is a popular trend that’s also known as the cleanse and detox diet. It involves switching out all meals for juices made from fresh fruit and vegetables for anything from 24-hours to 10-days. Many people have reported fabulous weight loss results from this diet however it can be a very difficult diet to maintain if you don’t plan it properly and is likely to cause headaches and fatigue. Juices tend to be high in sugar and low in fiber when compared to whole food products which can lead to frequent fluctuation of your blood sugar levels, that paired with the substantially lower calorie intake can ultimately increase the risk of unwanted headaches and less energy.


If you are interested in starting a new diet, it’s worth heading to a doctor or nutritionist to discuss any risks. Your health comes first!



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