The 3 Day Diet Guide: How It Works, Results + Potential Side Effects

The 3 day diet plan is another name for the 3 day Military Diet.

So, what exactly is the 3 day diet? What can you eat on the 3 day diet plan? Is there a good 3 day weight loss diet that actually works? What is a reasonable 3 day weight loss result to expect?

In this guide, we will discuss the 3 day diet, its pros and cons, potential 3 day weight loss results, and healthier alternatives that will help you lose weight in 3 days.

We will look at: 

• What Is the 3 Day Diet?
• How to Follow the 3 Day Diet Plan
• Is the 3 Day Diet Good for Weight Loss?

Let’s get started!

What Is the 3 Day Diet?

Despite being called the “military diet,” the 3 day diet plan is a fad weight loss diet popularized on social media designed to be a “quick fix” for rapid weight loss. 

Therefore, rather than being characterized as a healthy, sustainable dietary pattern like the Mediterranean Diet or DASH Diet, the 3 day weight loss diet is more of a crash diet that fails to provide adequate nutrition in a balanced and health-supportive way for the long term.

That said, due to the extreme nature of the 3 day weight loss diet and the way that fad diets often manage to obtain somewhat of a cult or viral following online, there are many social media posts where people have followed the 3 day military diet and reportedly achieved impressive weight loss success.

Therefore, while we do not support the principles of the 3 day diet as written if you like to follow an extreme diet for rapid short-term weight loss, you may be interested in learning about the 3 day diet plan.

How to Follow the 3 Day Diet Plan

Although the 3 day diet may sound like a 3 day weight loss diet and then you’re done, it’s actually a seven-day cycle that is supposed to be followed at least 4 times back to back for a total of one month or more.

The 3 day diet meal plan provides only 1,100–1,400 calories: Approximately 1,400 calories on day 1, 1,200 calories on day 2, and 1,100 calories on day 3.

Portions are also very small; you can see the full 3 day meal plan here.

After the 3 day diet meal plan with the above foods, you have four days of “free eating,“ though this is a bit of a misnomer because the diet is still restricted to 1500 calories, which again is well below the daily caloric recommendations for weight maintenance for most adults.

However, 1500 calories per day is much more reasonable for someone trying to lose weight in a healthier, sustainable way, particularly because you can choose more well-balanced meals with healthy fats, complex carbohydrates, more fruits and vegetables, fewer processed foods, and high-quality protein.

After these four days, many people go back onto the 3 day diet meal plan and begin to cycle again for at least four times, depending on their weight loss goals and commitment to the 3 day weight loss meal plan versus another weight loss diet.

In addition to these 3 day diet foods, the 3 day diet meal plan allows you to drink water and herbal tea as much as you want, and you can have caffeinated tea or coffee up to two times per day. 

However, you are not allowed to add any sugar, sweeteners, artificial sweeteners, milk, creamers, etc. to your drinks.

Is the 3 Day Diet Good for Weight Loss?

The 3 day diet plan is designed to be a weight loss diet.

In fact, the creators of the 3 day military diet promise rapid weight loss of up to 10 pounds (4.5 kg) in one week and 30 pounds in one month. 

Purportedly, the 3 day diet weight loss results are due to the fact that it severely restricts calories, and includes specific foods that the creators of the diet say “rev your metabolism” to aid weight loss results.

If you look at these 3 day weight loss claims, they are poorly founded on actual science.

You have to burn 3500 calories over what you consume to lose 1 pound of body fat, which essentially means that you have to create a caloric deficit of 3500 calories to lose a single pound.

Thus, in order to lose 10 pounds of fat in a week, you would need to create a caloric deficit over the week of 35,000 calories.

This works out to a daily caloric deficit of 5000 calories, which is virtually impossible, especially on a sustained basis for an entire week.

Similarly, though not quite as extreme, the 3 day weight loss diet says you can lose 30 pounds in one month, which is essentially equal to losing one pound per day.

Here again, this would require a daily caloric deficit of 3500 calories every single day of the month.

The 3 day diet meal plan is a high-protein diet that is extremely low in total calories, total fat, and complex carbohydrates.

Though there is no research backing these claims, the 3 day diet is said to induce a “metabolic boost” due to specific pairings of foods in the 3 day diet meal plan.

The severe caloric restriction on the 3 day weight loss diet will certainly create a caloric deficit for almost every adult, particularly if you have a larger body size and are physically active. 

According to the 2020-2025 United States Dietary Guidelines, adult men should consume a minimum of 2,200–2,400 calories, while adult females should consume at least 1,600–1,800 calories per day.

However, the claims that you can lose 10 pounds in one week are misleading.

Thus, the 3-day diet is a significant caloric deficit, but it is virtually impossible to create the caloric deficit necessary to lose 10 pounds of fat mass, so much of the weight loss you will experience on the 3 day diet plan is water weight.

Because the 3 day weight loss meal plan is a high-protein and a low-carbohydrate diet, you will burn through most of your glycogen stores (stored carbohydrates)

For every gram of glycogen the body stores, an extra 3-4 grams of water are also retained by the body.

Therefore, when you burn through your glycogen, you will lose a significant amount of water weight.

Water weight loss on the 3 day diet is accelerated as well due to the removal of alcohol and most high-sodium foods (except hot dogs), both of which also increase water retention.

Plus, because the 3-day diet meal plan is so meager in terms of caloric intake and volume of food, even the weight of the food in your digestive tract will decrease by a couple of pounds because you’re hardly putting anything in your stomach from a heft/mass standpoint.

All this is to say that you may see a significant drop in your body weight on the scale after following the 3 day weight loss diet, but a good portion of the weight lost on the 3 day diet will be water weight. 

This weight will return once you start eating more carbohydrates again and consuming a higher volume of food overall.

Most importantly, the military diet includes some highly-processed foods like hot dogs and foods with very low nutritional value, like saltines and vanilla ice cream, and it is very low in fiber.

Ultimately, the 3 day military diet is not advisable as a healthy approach to weight loss.

If you need to lose weight quickly, cutting carbohydrates will help shed water weight, but again this is not true fat loss.

Instead, the most sensible and sustainable approach to healthy weight loss is to strive for 1 to 2 pounds per week, by following a nutrient-dense diet and being physically active. 

You can decrease your caloric intake and increase your caloric expenditure to generate a modest caloric deficit of 500 to 1000 calories per day and aim to choose whole, natural, unprocessed foods from a variety of food groups rather than severely restricting what you are eating and how much you are eating.

A healthy diet that may fit your needs is the Mediterranean diet. Check out our guide here for more information.