In the world of diets, it can be overwhelming with the choices available — keto, paleo, flexitarian, just to name a few.
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But for those trying to lose a lot of weight, the protein-sparing modified fast diet, or the PSMF diet, may be a good short-term option.
Doctors typically recommend this diet for a person who has obesity. And you should be supervised by a doctor or registered dietitian while on the PSMF diet.
So, how does the PSMF diet work? By consuming low amounts of calories and carbohydrates and high amounts of protein, the idea is that weight loss happens quickly.
“It’s a modified keto,” says registered dietitian Beth Czerwony, RD. “The majority of your calories are going to come from protein. There’s very minimal fat and your options include lean protein with limited vegetables. You won’t eat fruits, starchy vegetables, breads or pastas. And this will help your body go into ketosis, which is a fat-burning mode.”
Czerwony explains how the PSMF diet works and its pros and cons.
How it works
The PSMF diet is divided into two phases: The intensive phase and the refeeding phase.
During the intensive phase, which typically lasts about six months, you’ll eat about 800 calories per day. The goal is to consume about 0.7 grams of protein per pound of your body weight.
When it comes to carbs, you’ll want to eat about 20 grams or less a day — with those carbs coming from vegetables. You’ll also need to avoid any added fats that come from foods like oils and salad dressings.
“Most of the time, people stay on it on average of about six months because they get bored, they get tired or they want some variety,” says Czerwony.
Your doctor or dietitian will monitor any nutritional deficiencies and may recommend that you take magnesium, potassium and/or sodium supplements.
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