One of my favorite TV shows is “My 600-Lb. Life,” so I’m pretty familiar with Dr. Nowzaradan — also known as Dr. Now — and his no-nonsense approach.

The diet program he uses to prepare patients for bariatric (weight loss) surgery has recently gained popularity as the Dr. Now Diet.

This restrictive diet should only be attempted by people who are preparing for weight loss surgery or who are at imminent risk of serious health concerns due to weight.

In addition, they should only follow the diet under the supervision of a medical team, including a doctor or surgeon and bariatric dietitian.

Here’s what you need to know about the Dr. Now Diet.

Diet review scorecard

• Overall score: 2.2
• Weight loss: 1.0
• Healthy eating: 2.5
• Sustainability: 3
• Whole body health: 2
• Nutrition quality: 2.5
• Evidence-based: 3

Summary: The Dr. Now Diet is designed to help candidates for preoperative weight loss surgery lose weight quickly. However, it’s extremely restrictive and should only be attempted under medical supervision.

The Dr. Now Diet is a very restrictive low carb, low calorie diet.

Dr. Nowzaradan is a Houston-based bariatric surgeon who specializes in weight loss surgery for people with morbid obesity.

He became famous for the reality show “My 600-Lb. Life,” which documents the lives of his patients who weigh more than 600 pounds (272 kg). The show follows their journey before, during, and after weight loss surgery.

Dr. Now is well known because he takes on patients many other surgeons think are too risky to operate on.

Before the patients have surgery, many of them need to lose weight to reduce their risk of complications and show they’ll be able to make the lifestyle changes doctors prescribe after surgery.

Dr. Now puts the patients on a strict low carb and low calorie diet to help them quickly lose weight in preparation for surgery. He details the diet in his book, “The Scale Does Not Lie, People Do.”

Summary

The Dr. Now Diet is a very restrictive low carb, low calorie diet. Dr. Now is a bariatric surgeon who gained fame on “My 600-Lb. Life.” He encourages his patients to lose weight prior to weight loss surgery using this diet.

Dr. Now’s book explains the three main principles of his diet approach using the acronym “FAT”:

• Frequency. This refers to how often you eat. Dr. Now recommends eating two to three meals per day with no snacks.
• Amount. This means how many calories you should consume. He says to limit calorie intake to 1,200 calories or less each day, divided evenly — so 400 calories for each meal 3 times daily, or 600 calories for each meal twice daily.
• Type. The types of food you eat are also important. He says to strictly avoid sugar and choose low fat and low carb foods while increasing the protein and fiber content of each of your meals. Protein and fiber can help make your meal more filling (1).

Dr. Now says that when you begin, make a list of all of your favorite foods, and then remove all the sugary, high fat, and high calorie foods from the list.

What remains should be a regular part of your daily meals while you’re doing the Dr. Now program — that way, it’s easier to stick to.

He also says to focus on minimally processed food and choose small portions, which will help make it easier to meet the restricted calorie count.

This diet is designed for short-term use in the lead-up to bariatric surgery, so don’t follow it for longer than a month or two.

Always make sure you’re under close medical supervision while you’re on this diet.

Summary

Dr. Now recommends sticking to 1,200 calories per day, divided evenly across two or three meals. The diet doesn’t allow snacks or sugary, high calorie, and high fat foods. Dr. Now advises eating more protein and fiber.

This strict, low calorie diet plan does result in fast weight loss, especially in people with higher body weight.

Dr. Now encourages many of his patients who weigh more than 600 pounds (272 kg) to try to lose 30 pounds (14 kg) in just 30 days, and many of them are successful.

In fact, the 1,200 calorie diet is commonly used for preoperative bariatric surgery patients, not just in Dr. Now’s practice.

In one study on 24 women with obesity, participants lost a significant amount of weight with and without exercise in just 13 days (2).

Doctors often recommend preoperative weight loss for people undergoing bariatric surgery because it appears to help reduce complications after the operation.

One study looked at outcomes in more than 480,000 people who had bariatric surgery. The researchers found that weight loss prior to surgery helped reduce the risk of death within 30 days of surgery — even when people lost less than 5% of their body weight (3).

Studies have also found that when people were required to lose weight before they were approved to have weight loss surgery, they tended to have more successful weight outcomes after surgery (4).

Summary

The Dr. Now Diet can induce rapid weight loss, and preoperative weight loss does appear to help improve outcomes in people who have weight loss surgery.

The Dr. Now Diet plan isn’t a good choice, except for those who need to lose weight to have a safe operation.

The 1,200 calorie limit is excessively restrictive for most people and therefore not sustainable.

In fact, long-term extreme calorie restriction might make it harder for you to lose weight.

That’s because your body adapts to calorie restriction by slowing down your metabolic rate, meaning you burn fewer calories. Low calorie diets may also affect your hunger hormones, making you hungrier than normal (5).

Research shows that many of these diets lead to rebound weight gain because of these metabolic changes. As a result, this and other crash diets aren’t a good choice if your goal is long-lasting weight loss (5).

Additionally, very calorie-restricted diets often provide inadequate amounts of nutrients, even if they’re rich in nutrient-dense fruits and vegetables.

For example, one study noted that a high protein, low carb, 1,200 calorie diet — similar to the one Dr. Now recommends — came up short on thiamine, vitamin D, vitamin E, calcium, magnesium, and potassium (6).

While these gaps may not pose immediate health risks, they could lead to complications in individuals following the diet for more than a short-term basis of a few weeks.

Restrictive diets also cause changes to the gut microbiota, the beneficial bacteria that populate your large intestine.

Maintaining a healthy balance of these gut bacteria is crucial for optimal health and digestion. However, restrictive diets may reduce both the overall population and the diversity of the bacteria present (7).

Finally, don’t attempt the Dr. Now Diet without medical supervision, especially if you have any medical conditions or are taking medications. If you’re looking to try this diet, be sure to speak with a healthcare professional beforehand.

Summary

Dr. Now’s diet plan isn’t a good choice for most people. It’s only suitable for certain situations, like prior to weight loss surgery. It’s restrictive and not sustainable, and don’t attempt it without medical supervision.

The following lists detail foods to eat and avoid while on the Dr. Now Diet.

Foods to eat

Dr. Now’s diet plan allows these foods, along with other high fiber, high protein, low fat, and sugar-free foods.

• Lean protein sources: egg whites, lean cuts of meat, chicken breast, turkey breast, beans, tofu, fish
• Fats and oils: cooking spray, small amounts of oil for cooking
• Lower sugar fruits: all whole fruits, except watermelon, cantaloupe, banana, and mango
• Most vegetables: all vegetables, except potatoes
• Certain nuts and seeds: flax seeds, chia seeds
• Nonfat dairy: plain nonfat yogurt, skim milk
• Whole-grain carbs: wheat bread, wheat or corn tortillas, whole-wheat pasta in moderation
• Zero-calorie sweeteners

Foods to avoid

Dr. Now provides his patients undergoing bariatric surgery with a list of foods to avoid on the diet. The list includes foods you would expect, like cookies and French fries, but also some surprising foods, like oatmeal, popcorn, and peanuts.

His reasoning is that oatmeal is high in carbs, popcorn is often doused in fat, and peanuts are high in calories and easy to overeat.

Here are the foods to avoid on Dr. Now’s diet plan:

• Some sources of protein: high carb or sugary protein shakes, high fat meats, processed meats (like hot dogs, bacon, sausage), battered and fried meats (like fried chicken), eggs
• Some fats and oils: butter, olive oil, vegetable oils
• Fruits higher in sugar: fruit juices, fruit canned in syrup, fruits that have more natural sugar (watermelon, cantaloupe, banana, and mango)
• Potatoes: includes French fries
• Most nuts and seeds: peanut butter, peanuts, almonds, cashews, pistachios, sunflower seeds
• Full fat and sweetened dairy: sweetened yogurt, sorbet, ice cream, milkshakes, chocolate milk, full fat cheese
• Certain carbs, especially refined products: crackers, chips, popcorn, white rice, brown rice, waffles and pancakes, white bread, pasta
• Sugar-containing sweets: cookies, candy, cakes and pastries, ice cream, honey, syrup

Dr. Now encourages avoiding several nutritious foods due to their calorie content, including eggs, olive oil, nuts, and seeds.

In addition, Dr. Now suggests limiting whole-wheat bread and other whole-grain carbs, although they’re not totally banned from the diet.

Summary

Dr. Now encourages eating high protein, high fiber, low calorie, low fat, and sugar-free foods on his diet program. The diet bans several nutritious foods due to their calorie content, including oatmeal, olive oil, nuts, and eggs.

Here’s a sample menu you could follow for 3 days on the Dr. Now Diet. Since there are no snacks allowed on the diet, you’ll only see breakfast, lunch, and dinner suggestions below.

Day 1

• Breakfast: 2 ounces (57 grams) egg whites with spinach, mushrooms, and 1 ounce (28 grams) part-skim mozzarella on 2 pieces whole-wheat toast, ready-to-drink low carb protein shake
• Lunch: 3 ounces (85 grams) grilled chicken, salad with 2 tbsp. (30 grams) vinaigrette dressing
• Dinner: 3 ounces (85 grams) broiled salmon with asparagus

Day 2

• Breakfast: 1 cup (245 grams) plain nonfat yogurt with stevia and 1/2 cup (75 grams) blueberries, 1 cup (240 mL) skim milk, 2 pieces turkey bacon
• Lunch: 1 cup (238 grams) tuna salad made with nonfat Greek yogurt instead of mayo, whole-grain pita, celery, and carrots
• Dinner: spiralized zucchini with 4 ground turkey meatballs, marinara sauce, and 1 ounce (28 grams) part-skim mozzarella

Day 3

• Breakfast: fruit smoothie with 1 cup (240 mL) skim milk, 1 scoop protein powder, 1 cup (150 grams) strawberries, 1/2 avocado
• Lunch: 1 cup (240 grams) broccoli stir-fry with 3 ounces (85 grams) tofu
• Dinner: 2 cups (478 grams) low fat chicken and vegetable soup, side salad with 1 tbsp. (15 grams) vinaigrette dressing

Summary

The above meal plan details 3 days of meals that provide approximately 400 calories in each meal and stick to the foods allowed on the Dr. Now Diet.

The Dr. Nowzaradan Diet, or Dr. Now Diet, is a restrictive, 1,200 calorie diet designed to promote rapid weight loss in people who are about to undergo weight loss surgery.

While it does have its place in certain medical contexts, it’s not for most people — and certainly not a suitable option if you’re looking for a diet that you can stick with long term to promote slow and sustainable weight loss.

The diet should also be done under medical supervision.

Unless a healthcare professional has recommended you try this diet, it’s likely best to avoid it. Instead, consider making gradual lifestyle changes that result in lasting weight loss.