What Exactly Is the 4-Day Diet, and How Effective Is It?

4 day diet

What’s the Rina or 4 Day Diet?

The 4 Day Diet, commonly called the 90-Day Diet or Rina Diet, is rapidly gaining popularity, but why? Can it be an effective, healthy way to lose weight over the course of several months? Get the low down on this weight loss solution!

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It’s time for a nutritional change: Rina Diet

All diet plans usually make the same promise: lose weight fast, feel better! However, science and personal experience beg to differ. There are plenty of diets that many self-proclaimed experts swear burn fat fast only to help you put it back twice as fast.

The yo-yo effect of many diets is an issue we face lowering our trust in nutritional programs and people promoting them.

However, while we dissected plenty of bad diet tips we heard throughout the years, one diet seems to stand the test of time and gain popularity among people and health specialists as well.

We are talking about the Rina Diet, known as the 90 Days Diet or the 4 Day Diet. Some people swear by it, while some cardiologists and nutritionists begin to see its long-term advantages.

Before we dive into the science behind the Rina Diet, let’s see how it compares to the Ketogenic diet.

Rina Diet or Ketogenic Diet?

Rina 4 Day eating regimen is a new way to diet. Its principles protect dieters from the dreaded weight yo-yoing and have a generally more positive effect on the body than the majority of weight loss plans.

Like any other approach to shedding those extra pounds, Rina offers nothing fundamentally new. It is based on dissociated food intake and proceeds from the (hitherto unproven) premise that humans cannot metabolize mixed foods as effectively as they can the foods from one group. It suggests adhering to one alimentation group per day on each of the 4 days of the cycle that is supposed to repeat itself for a total of 90 days. More on this in the next section.

On the bright side, dieters on Rina regimen are less likely to cave into their food cravings, they keep metabolism in check by training the digestive systems to process specific types of food during a specific time of the day, and it is more of a lifestyle habit than a diet per se.

The cons of the diet are as follows:

  • You don’t get a sufficient amount of meals per day
  • You have the green light to indulge in junk food
  • You don’t have nutrient diversity from day today

Its close rival and a worthy alternative is the ketogenic diet or keto diet. This regimen aims at nudging the body into relying on fat stores rather than glucose to provide energy. Thanks to keeping the blood sugar levels drastically low at all times, it helps to increase the caloric expenditure and streamline the “metabolic work”. The diet has also proven positive effects in people with unresponsive epilepsy.

However, the downside is also there: increased load on the kidneys, keto-flu, dizziness, cramps, constipation, low blood pressure, and other symptoms, many of which result from ketonic toxicity.

How to prevent these symptoms and ensure that your diet brings about only positive changes? It is essential to make sure that your body is in the state of ketosis, and not ketoacidosis. The difference between these two states is this: while the former is a natural response of the body to intermittent fasting or a low-carb diet, the latter is a dangerous condition in which the higher-than-normal level of ketones causes blood acidity.

To the rescue is a ketone breath meter, a smart device that analyzes your breath to determine the number of ketones in your body. This testing equipment is indispensable whichever low-carb diet you choose to adhere to, and even if you suffer from health conditions that put you in the risk group for developing ketoacidosis.

Now that we have a little foundation on the difference between the two diets you might be thinking about trying out, let’s take a look at the Rina diet’s main principles and try to figure out if it works!

The Science Behind the Rina Diet

What Is the 4 Day Diet and Does It Really Work-The 4-day diet can be traced back to athletes who wanted to offer regular people the chance to live a healthy and pleasant life by following an athlete’s way of eating and approaching nutrition.

In other words, the Rina diet comes with no true restrictions: you can have a burger, a pizza, some cake, and plenty of other delights – as long as you follow the rules on how and when to eat them.

Scientifically speaking, the Rina diet focuses on the human inability to actually process multiple types of food at once. Many of our digestive problems and subsequent health issues come from the fact that we mix and match all kinds of foods in one serving or during the same day.

This is why Rina dissociates foods.

How to Implement the Rina Diet?

The Rina diet is founded on a relatively simple principle: you eat four types of main foods, one food a day, in a four-day cycle that repeats for 90 days (hence the alternative diet names).

The difference between Rina and other diets is that it isn’t a crash one – you don’t lose 30 pounds in one week, you lose them in three months. The supporters of the Rina diet consider it not being a diet at all, but a new lifestyle that trains and strengthens your metabolism.

  • Principle 1: No matter what type of food you eat one day, you should have only fruits for breakfast. This might sound a little strange, but fruits help your digestive system work properly. No matter what you have for lunch or dinner throughout the 90 days period, your morning breakfast should contain fruits only.
  • Principle 2: You need to keep a schedule of what and when you eat. Rina’s diet allows you to have breakfast between 7:00 a.m. and 11:00 a.m., lunch between 12:00 p.m. and 2:00 p.m., and dinner between 6:00 p.m. and 8:00 p.m. There are no intermediate snacks in between the main three meals and no dinner later than 8:00 p.m.
  • Principle 3: All throughout the 90 days of dieting, your dinner has to be ½ of the food quantity you had for lunch.
  • Principle 4: Drink a lot of water all day long and try engaging in cardio exercise at least once in two days.

The Rina 4 Day Diet Cycle

Day 1 – Protein Day

  • Breakfast: fruits (accompanied by seeds and nuts if you like)
  • Lunch: this is the day when you can have proteins in the shape of lean, broiled, grilled, or roast meat, fish, eggs, or dairy products – if you choose one type of protein source, keep it all day long and don’t mix meats with cheeses. Also, don’t mix steak with fries, but you can always have a large side of fresh salad.
  • Dinner: the same protein source with a salad – but half the portion you had for lunch.

Day 2 – Starch Day

  • Breakfast: fruits (accompanied by seeds and nuts if you like)
  • Lunch: this is the vegetable day, so you can have any kind of boiled or roast veggies: peas, green beans, corn, lentils, carrots, potatoes, beans, etc. You can also have some rice or a slice of bread, salads, and seasoning.
  • Dinner: same as lunch, but half the quantity

Day 3 – Carbohydrates Day

  • Breakfast: fruits (accompanied by seeds and nuts if you like)
  • Lunch: you can have pasta and pizza (without meat or cheeses), but mixed with veggies, tomato sauces, and other carbs’ sources. This is the day when you can have a slice of cake, some dark chocolate, or a scoop of ice cream.
  • Dinner: same as lunch, but half the quantity

Day 4 – Vitamins Day

  • Breakfast: fruits (accompanied by seeds and nuts if you like)
  • Lunch: this is the day when you can eat all possible fruits and vegetables, preferably raw or steamed. Fruit salads, veggie salads, nuts, seeds, and cooked legumes can be eaten every two hours.
  • Dinner: don’t forget to have your last serving of fruits and veggies before 8:00 p.m.

After this 4-day cycle, you should repeat the whole program, starting again with the protein day.

Another main aspect of the Rina diet is Day 29 – it is an important landmark of the program, as you should be able to spend a whole day drinking only water and not eating anything else. Some people aren’t able to go through this day, but you should at least try.

If it is too hard, keep up with the vitamins’ day.

How Does the 4 Day Diet Truly Help?

As we said, Rina is not a short-term diet, but a lifestyle change that trains your metabolism and internal organs to work better. In order to keep the results (Rina helps you lose between 30 and 50 pounds during the 90 days), you should also implement a “maintenance” program for another 90 days.

The maintenance program also requires you to eat only fruits for breakfast, but make small dietary changes: if you had proteins for lunch, you can have legumes for dinner for instance.

More Tips to Make the Rina Diet Work

Just like any other diet, the 4-day diet is based on your willpower. The main idea is to not skip any of the four main foods in the cycle, as they are essential for human survival.

Sometimes you can go sideways and have a small portion of a certain type of food during a day bound to a different type of food.

However, if you keep the 80-20 proportion (80% of what you eat is on the plan and 20% is off the plan), you will be able to lose weight naturally.

Also, probiotics are always a good idea whenever you’re switching to a new diet. Check out DigitalHealthPost.com to see their recommendations on getting a good probiotic for you.

As per experts, high-intensity interval training workouts with strong pre-workout supplements can also greatly help you to achieve your fitness goals.


No matter what happens, keep in mind to drink plenty of water and engage in physical exercise, be it cardio, running, Pilates, yoga, or just power walking.

Rina or the 4-day diet, while having strong scientific roots in medicine and science, is not a miracle cure that allows you to magically tone and firms your body in the absence of physical training.

Have you ever followed the Rina diet? Did it work?

Updated 5/6/18

After graduating from University of Colorado, Master of Public Health, Ethel Huizar decided to develop a career as a health writer. Now she is a Contributing Editor at Home Remedy Book, where she writes about health problems and concerns, aiming to help people lead nourishing lives.
Ethel Huizar
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What Exactly Is the 4-Day Diet, and How Effective Is It?