For years, several diets for weight loss have emphasized protein while minimizing carbohydrates. But while the slow carb diet also uses that approach, it offers very detailed guidance on foods to eat and avoid, along with supplements to consider.
The slow carb diet was created in 2010 by entrepreneur and lifestyle guru Timothy Ferriss, who wrote The 4-Hour Body. The book was a New York Times bestseller, and the slow carb diet took off.
But while the slow carb diet has some similarities to other high protein diets like the keto diet, it’s definitely different. Here’s what the slow carb diet involves, plus whether dietitians think it’s worth trying.
Meet the experts: Scott Keatley, R.D., is co-owner of Keatley Medical Nutrition Therapy; Keri Gans, R.D.N., is author of The Small Change Diet.
What is the slow carb diet?
The slow carb diet is an eating plan that’s based on five rules. “It’s not unreasonable to expect to lose 10–20 lbs of fat,” Ferriss wrote of the diet on his blog. “This is true even without exercise.”
The slow carb diet leans heavily into the idea that you can get big results from making small changes. Ultimately, the slow carb diet promises to help people burn fat and lose weight.
Ferriss provides a lot of details about the diet, including a list of foods that are allowed over the course of six days. On the seventh day, followers are encouraged to have a cheat day where they can eat whatever they want.
During the six main days, followers are encouraged to have several meals a day, focused on five main food groups: animal protein, vegetables, legumes, fats, and spices. You should also avoid refined carbohydrates, fruits, and high-calorie drinks on the diet.
Each meal should focus on animal protein, vegetables, and legumes, and you can have as much of these as you’d like. Ferriss also suggests taking certain supplements, but notes that it’s not a required part of the diet.
How to follow the slow carb diet
The slow carb diet has five rules that followers are expected to adhere to:
Avoid ‘white’ carbohydrates.
That includes carbs that can be white. Meaning, no bread, pasta, rice, potatoes, or grains.
Eat the same meals.
You don’t need to have the exact same thing at every meal, but the diet encourages having just a few of the same dishes, especially for breakfast and lunch.
Avoid drinking your calories.
The diet encourages having plenty of water. Followers can also have unsweetened tea, coffee, or any other calorie-free beverage, but discourages drinks that contain significant calories. The diet has an exception of one to two glasses of dry red wine per night.
Don’t eat fruit
Ferriss says that fructose, the sugar in fruits, can increase blood fat levels.
Have one cheat day a week.
Ferriss encourages followers to “go nuts” during this day.
What foods can you eat on the slow carb diet?
The diet breaks foods into five groups: protein, legumes, vegetables, fats, and spices. Ferriss recommends picking a few foods from those groups and sticking with them because, as he says, the more foods you can choose from, the more likely you are to go off of the diet.
The slow carb diet recommends building your diet around these foods:
Proteins
- Eggs
- Chicken (breast or thigh)
- Fish
- Beef (preferably grass-fed)
- Pork
- Lamb
Legumes
- Lentils
- Black beans
- Pinto beans
- Red beans
- Soybeans
Vegetables
- Spinach
- Mixed vegetables (broccoli, cauliflower, or any other cruciferous vegetables)
- Sauerkraut, kimchi
- Asparagus
- Peas
- Broccoli
- Green beans
The diet suggests having less of these foods:
Fats
- Butter
- Olive oil (for cooking)
- Grapeseed or macadamia oil (for cooking)
- Nuts
- Ghee
- Creamer (dairy-free, up to 2 teaspoons a day)
Spices
- Salt
- Garlic salt
- White truffle sea salt
- Herbs
Foods to avoid on the slow carb diet
While the slow carb diet doesn’t put limits on how much you can eat, it does suggest avoiding these foods:
Fruits
That includes both fruit and fruit juices. (However, you can have these on the cheat day, if you want.)
Dairy products
While butter and ghee is allowed, traditional dairy products like milk, cheese, and yogurt are not.
Refined carbohydrates
Ferriss refers to these as “white” carbs, which includes bread, pasta, rice, potatoes, and grains.
What is the slow carb diet cheat day?
The slow carb diet cheat day is part of the main principles of the diet. During this day, Ferriss says you can have whatever you want. He suggests picking one day a week to do this to “go nuts.” His recommendation is Saturday.
Slow carb diet supplements
Daily supplements are not required on the slow carb diet, but Ferriss suggests several to help fill nutritional gaps and support weight loss. Those include:
- 99 mg of potassium
- 400 mg of magnesium
- 1,000 mg of calcium
- 20 to 25 mg of policosanol
- 100 to 300 mg of alpha-lipoic acid
- 325 mg of epigallocatechin gallate
- 200 mg of garlic extract
There are a few potential benefits to going on the slow carb diet. Cutting out things like “white” carbohydrates “eliminates common sources of calories and potential blood sugar spikes, which can lead to overeating and cravings,” says Scott Keatley, R.D., co-owner of Keatley Medical Nutrition Therapy.
The diet’s restrictive nature can lead to weight loss, says Keri Gans, R.D.N., author of The Small Change Diet. “Almost any time you eliminate an entire food group, such as fruit and dairy, you will lose weight,” Gans says.
The emphasis on unprocessed, high-protein foods may help some people feel fuller and more satisfied while promoting muscle preservation, Keatley says. “It also removes many calorie-dense, low-nutrient foods, which can lead to short-term weight loss success,” he adds.
The diet is also big on eating plenty of vegetables and legumes, which are packed with nutrients, Gans points out. “In the beginning, another pro for some individuals is the very limited menu,” she says. “Fewer daily choices to make can make it easier to stay on course.”
There are some definite cons to this diet, according to nutritionists. “This approach is overly simplistic and risks demonizing nutrient-dense foods like fruit and dairy, which provide essential vitamins, minerals, and other health benefits,” Keatley says.
The supplements are likely recommended because the diet is so restrictive, he says. “While supplements may mitigate some issues, they can’t fully replace the variety of nutrients available in whole foods, making the reliance on them a red flag for the diet’s overall quality,” Keatley says.
While Gans says the diet’s repetition may be helpful at first, it can get old after a while. “This will eventually become a con as the repetition will cause many people to rebel,” she says.
Gans also isn’t a fan of the diet removing entire food groups, which is a move that she calls “misguided.”
Sample slow carb diet meals
There is no calorie counting on the slow carb diet, and Ferriss says you should eat as much as you’d like. However, he recommends picking three to four meals and repeating them for at least the first two weeks. Sample meals he suggests:
Breakfast
Three scrambled whole eggs, lentils, and spinach
Lunch
Grass-fed organic beef, pinto beans, mixed vegetables, and extra guacamole
Dinner
Salmon, asparagus (or lentils), and coconut cauliflower curry mash
Is the slow carb diet safe?
In the short term, the diet can be safe. But dietitians have concerns about long-term healthy while following the slow carb diet.
“For most individuals, the slow carb diet is not a sustainable or optimal approach to weight loss,” Keatley says. “While it may deliver short-term results, its restrictive nature and reliance on supplements make it less appealing compared to balanced dietary patterns that include a variety of nutrient-dense foods.”
Gans also doesn’t recommend trying this diet. “Far better, less restrictive, healthier options are available that will promote weight loss and keep a person’s sanity,” she says.
Dietary supplements are products intended to supplement the diet. They are not medicines and are not intended to treat, diagnose, mitigate, prevent, or cure diseases. Be cautious about taking dietary supplements if you are pregnant or nursing. Also, be careful about giving supplements to a child, unless recommended by their healthcare provider.
