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Why the 5:2 Diet (Fasting Diet) Doesn't Work

Why the 5:2 Diet (Fasting Diet) Doesn't Work

Dieting is not an art form nor is it something that should be of immense difficulty. Dieting comes down to simple math and science.

The laws of thermodynamics state that in order to lose weight we must simply intake less calories than we are putting into the body either by way of eating less food or expending more energy. However, time and time again new fad diets promising a huge range of results will appear with fancy guidelines and techniques geared towards success.

Related: Intermittent Fasting Diet - Is it For You?

People hopping from diet to diet each hope to see amazing results with little to no effort. One of the newer diets that have appeared is the 5:2 diet or the fasting diet.
5 2 Fasting Diet

How the 5:2 Diet Works - Extreme Fasting

The 5:2 diet essentially encourages fasting two non-consecutive days of the week and eating without caloric restriction the other five days of the week. The two fasting days may be completely fasted or allow for extreme caloric restriction.

The diet states that men should remain under 600 Calories on fasting days while women should remain under 500 Calories. While this diet in theory could work for some individuals, the truth of the matter is this plan is flawed in several ways setting the dieter up for likely failure.

The 5:2 Diet Encourage Extreme Fasting

Extreme fasting is detrimental. While intermittent fasting calls for 16 hours of fasting with approximately 8 hours of eating, the 5:2 diet recommends eating under 600 calories per day. For most men and women this equates to eating only about 25% of the daily recommended value of calories for healthy individuals.

This likely will result in the person feeling lethargic, drowsy, and severely lacking energy. Furthermore, training on these days with such low calories will be nearly impossible due to lack of energy. While it is possible these low calorie days can be offset as rest days it's always nice to be able to train as an option regardless of the day's current diet.

The 5:2 Diet Encourages Binge Eating

By creating a plan that encourages people to not count calories five days of the week, the likelihood of binge eating is vastly increased. Eating just a few hundred calories extra on the five non-fasting days will completely negate the fact that fasting occurred two days of the week.

People are always better off maintaining a constant caloric deficit every day of the week to slowly progress towards their goals. If people on the 5:2 diet get the idea that they may consume whatever they want most of the time there is a stronger likelihood of over indulging on fatty, sweet, calorie-dense food items.

The 5:2 Diet Can be Unsafe

Fasting can be unsafe. There are several short and long term side effects associated with fasting. In the short term people not used to fasting may experience symptoms including: headaches, dizziness, lightheadedness, fatigue, low blood pressure, and heart arrhythmia.

Furthermore, lower energy levels and fatigue may hinder the ability to perform the necessary daily tasks for survival. Also, research has shown that in some cases fasting may actually slow down one?s metabolism.

In the long term, fasting can negatively affect the functions of the body?s organs including the liver and kidneys. While some people may be able to function fasted the vast majority of the population will tend to experience some sort of ill side effects.

The 5:2 Diet is a Poor Way of Entering a Calorie Deficit

Caloric restriction is simply just numbers. Whether you are cutting 3500 calories per week on a daily basis or just a couple of days, the caloric restriction for the week will remain the same.

However, by severely lowering your calories a couple of days per week you will have difficulty performing a solid workout or even just functioning at optimal levels. This is in stark contrast to a moderate caloric deficit daily that will not hinder your energy levels and overall life performance.

The Bottom Line

Any type of diet simply comes down to taking in less energy than your body needs to maintain it's current state by way of caloric restriction or energy expenditure. There is no need to take drastic measures or follow trendy fad diets to reach your overall weight loss goals.

Practice moderation and consistency in order to achieve the absolute best results possible.

Be sure to follow me on Instagram @ryanrodal and subscribe to my YouTube channel MuscleMinds for more great nutritional advice and workout tips!
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