The PSMF diet (Protein Sparing Modified Fast)

THE PRINCIPLES OF THE DIET

The primary goal of the PSMF (Protein Sparing Modified Fast) diet is to promote rapid mass loss while preventing loss of muscle mass. To do this, the diet must keep insulin levels low. This avoids storing carbohydrates by turning them into fatty tissue. It is advisable to have regular physical activity while doing this diet.

To promote the production of glucagon rather than insulin, the priority must be to reduce carbohydrate intake as much as possible.

• All foods containing large amounts of carbohydrates are therefore prohibited in the diet: bread, sugary products, cereals, and a majority of fruits.
• Fat intake is also reduced to a minimum : a few grams of oil are allowed each day.
• To avoid loss of muscle mass, proteins are important during the diet: they can be found in meat and fish.

The main foods allowed are : fish, shellfish, egg white, poultry, chicken, lamb, low-fat cheese, low-carb vegetables such as mushrooms, zucchini, asparagus, carrots, broccoli, cauliflower…

Foods to avoid are : fatty meats, milk, fruit juices, sodas, sausages, breads, fruits rich in carbohydrates.

The PSMF diet has several phases to follow for about a month . It is not recommended to follow this diet any longer to avoid health problems. Before starting such a diet, it is recommended to seek the advice of your doctor, to avoid deficiencies that can lead to more serious complications for the body.

1- Active stage

This attack phase of the PSMF diet is very low calorie and should last a maximum of one week . It helps to wake up the metabolism and reduce insulin production to tap into fat stores.

Typical menu during the active phase

Don’t forget to take all the necessary nutritional supplements: potassium, sodium, calcium, omega3.

2- Transition phase

This phase of the PSMF diet allows you to slightly increase the level of calories ingested while continuing to keep insulin levels rather low. Mass loss is less impressive during this phase, which can last between one and two weeks .

Standard menu of the transition phase

Here again, food supplements are essential, as well as the consumption of a sufficient quantity of water.

3- Maintenance phase

This period can last several weeks and makes it possible to maintain a gradual weight loss and to limit as much as possible the regain of weight after stopping the diet.

Typical menu of the maintenance phase

You can continue to take certain nutritional supplements if you feel the need. Continue to drink between 1.5 and 2L of water per day.

ADVANTAGES

The main benefit of the PSMF diet is very rapid weight loss . This is a particularly low-calorie diet, especially in the active phase. During four weeks of dieting, you can expect a loss of about 4 to 6 pounds, mainly of fat . Muscle loss is limited, especially if physical activity has been maintained during the diet, which is highly recommended.

Other benefits can be seen in the body. The drop in the level of insulin increases the risk of insulin resistance , especially in patients with type 2 diabetes. This drop also leads to a drop in the level of glucose in the blood, which leads to the establishment of a new metabolism.

The PSMF diet is also quite simple to set up and requires only a scale and little time in the kitchen. The list of authorized foods is rather simple to find. It is possible to eat frozen foods if certain foods are not grown in certain seasons. Be careful, however, to weigh the food well before putting it to cook and to vary the meals according to your desires.

DISADVANTAGES

The PSMF diet should be approached with caution and it is generally not recommended to start it without the advice of a doctor. The massive reduction in calories ingested associated with the disappearance of carbohydrate foods can lead to weakness during the day, especially if physical activity is continued.

The sudden change in diet can lead to other much more troublesome side effects: diarrhea or constipation, hair loss, hypotension, menstrual disturbances or even headaches . These symptoms may only be temporary but are nonetheless difficult for some people to live with. In the long term, such a diet can also become dangerous for the cardiovascular system by increasing cholesterol levels and blood pressure. A diet that is too high in protein can also become toxic to the kidneys.

It is also extremely difficult to maintain a social life during the follow-up of the diet because of the few authorized foods and especially the prohibition of carbohydrates and the limitation of fats. In addition, the resumption of lost weight is almost inevitable in the months following the end of the diet. It is therefore important to consult your doctor before starting and taking the prescribed nutritional supplements.

ORIGINS OF THE REGIME

The PSMF diet is the ancestor of high protein diets like the Dukan diet. It comes from a work written by Dr. Georges Blackburn in 1971. This work is entitled  Protein Sparing Modified Fasting  which can be translated as  “Modified diet with protein preservation” . Professor at Harvard University and researcher, he was able to establish the body’s protein needs that help preserve muscle mass during a fast.

But in 1977, a few years after the book was published, more than 50 people died of heart problems. These had in common to have followed this diet in particular. Protein supplements used during fasting have been shown to be of poor quality and lacking in an amino acid called tryptophan.