The slow-carb diet may help with weight loss, but is it safe?

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Not all low-carb diets are built the same. While many popular diets for weight loss like Whole30 and keto primarily focus on protein, fresh produce, and limiting carb intake, the slow-carb diet focuses on a list of specific weight loss-friendly foods and restricting refined carbohydrates. But what is a slow-carb meal plan, exactly, and how does it work?

The meal plan was created by entrepreneur and podcaster Timothy Ferriss, author of The 4-Hour Body: An Uncommon Guide to Rapid Fat Loss, Incredible Sex, and Becoming Superhuman. In his 2010 book, Ferriss outlines his trademarked ‘slow-carb diet’ which involves eating meat with legumes and vegetables for almost every meal of the day and swapping refined carbs with ‘slow’ carbs —AKA ones that take longer to digest.

Although ‘slow carb’ isn't an official nutrition term, the trendy diet remains popular for weight loss. But what can you eat on a slow-carb diet, and is it actually safe to try? Here are the benefits, risks, foods list, and things to keep in mind when trying it for yourself, according to a registered dietitian.

Meet the expert: Brigitte Zeitlin, is a registered dietitian and owner of BZ Nutrition in New York City.

What is the slow-carb diet?

First, what is a ‘slow carb’? The phrase relates to the concept of simple versus complex carbs: Simple carbohydrates move through the body at a faster pace than complex ones such as legumes or dark leafy greens, says Brigitte Zeitlin, a registered dietitian and owner of BZ Nutrition in New York City. Simple carbs end up being less filling and satiating — plus, they spike your blood sugar compared to complex ones due to the removed fibre. In short: complex carbs = ‘slow carbs’.

The slow-carb diet involves eating five main food groups (animal protein, vegetables, legumes, fats, and spices) across four meals a day for six days of the week, and focusing on carbs that take longer to digest. You get one ‘free day’ per week on which you can eat whatever you want, Zeitlin says.

‘The idea is to follow a very low-carb regimen on the premise that it will increase your body’s ability to break down fat for energy and reduce your overall fat stores,’ Zeitlin says — and in turn, reduce your body weight. By following the slow-carb diet, you might be able to lose 10-20 pounds (4-9kg) in one month even without exercising, per the founder's website. You're also welcome to take various supplements (like calcium and magnesium) while doing the diet, but they aren't a requirement, per the website.

Slow-carb diet rules

The slow-carb diet is based on the following five fundamental rules, per the founder:

1. Avoid ‘white’ starchy carbohydrates

If you are on this diet to lose weight, then you need to avoid all processed carbohydrates (like breads, pastas, cereals, baked goods, etc) for six days per week. If you are on the diet to increase your muscle and strength, then you’re allowed to eat these foods within 30 minutes of finishing a resistance-training workout.

2. Aim to eat the same meals and foods consistently

The slow-carb diet encourages you to re-make the same meals from the approved five groups of foods (animal protein, vegetables, legumes, fats, and spices). That said, eating a variety of different foods boosts your health and helps you manage your weight, per the CDC — so while it's helpful to stick to a few weight loss-friendly foods, don't feel like you have to restrict yourself entirely.

3. Prioritise low-calorie drinks (especially water)

The slow-carb diet boasts the importance of drinking water and other unsweetened tea or coffee drinks. Consuming alcohol, juice, smoothies, or any calorie-filled beverage is discouraged. (If you love a treat and can't stay away, try a low-calorie cocktail or healthy smoothie that will satisfy your sweet tooth and support your health goals.)

4. Don't eat fruit

This diet bans all fruit intake on the premise that they contain too much sugar for weight loss. However, it's worth noting that many experts still recommend fruit on a weight loss plan.

5. Take one day ‘off’ of the diet every week

Based on the slow-carb diet guidelines, you can eat and drink anything you wish on one day per week of your choosing. You may have heard this called a ‘cheat day,’ but we prefer ‘taking a break’. Enjoy yummy foods and make note of how your body feels — you even may find that your new routine has changed how you view healthy, satiating meals.

Foods to eat on the slow-carb diet

The diet is based on five main food groups: protein, legumes, vegetables, fats, and spices. The founder recommends eating these exact foods over and over without adding new options — but of course, no diet is one-size-fits-all, and you're encouraged to find nourishing foods that work for you and your lifestyle. In the meantime, here are the suggested foods for the slow-carb diet:


  • Eggs

  • Cottage Cheese

  • Chicken

  • Beef

  • Pork

  • Fish


  • Lentils

  • Black beans

  • Pinto beans

  • Red beans

  • Soybeans


  • Spinach

  • Asparagus

  • Peas

  • Green beans

  • Sauerkraut

  • Kimchi

  • Avocado

  • Tomato

  • Cruciferous veggies (broccoli, cauliflower, kale, Brussels sprouts)


  • Butter

  • Olive oil

  • Grapeseed oil

  • Nuts


  • Salt

  • Pepper

  • Herbs

  • Seasonings

Foods to avoid on the slow-carb diet


  • Pasta

  • Bread

  • Rice (white and brown)

  • Crackers

  • Cereals

  • Oats

  • Quinoa

Fruits and starchy vegetables

  • Bananas

  • Berries

  • Citrus fruits

  • Potatoes


  • Milk

  • Cheese

  • Yoghurt

  • Cream

Fried food and dessert

  • Ice cream

  • Cake

  • Cookies

  • Fast food

Sugary drinks

  • Fizzy drinks

  • Juice

  • Sweet coffee drinks


  • Sweet wine (except for dry red)

  • Cocktails

  • Beer

Sample meal plan for the slow-carb diet

One of the main rules of the diet is that you're encouraged eat the same things over and over to get you in a routine — a variety of meals is not necessarily the goal or purpose here. The following are a few examples of meals you could enjoy that fit the slow-carb diet bill, according to Zeitlin:


  • Scrambled egg whites (or with one yolk)

  • Spinach omelet

  • Cottage cheese with sliced almonds


  • Grilled chicken with asparagus

  • Lentil bean salad

  • Spinach salad with tuna fish

  • Black beans topped with guacamole


  • Salmon with roasted broccoli

  • Pork and sauerkraut

  • Grilled steak with cauliflower

  • Shrimp and kimchi

  • Chicken breast with black beans

Slow-carb diet benefits

The diet cuts out processed foods, sugary beverages, and other less-nutritious foods, and doing so can certainly yield weight loss results. Allowing for a day of eating whatever you want may help some people feel less deprived, too. (However, the opposite can also be argued).

The online reviews about the slow-carb diet are mixed, but there are certainly lots of positive ones. ‘Even if you don't actually apply any of the techniques, this book will likely make you think about your overall health in a different way,’ one reviewer wrote on Amazon. ‘There is a wealth of information in this book, and it has helped me lose weight, gain strength, and run faster in the last 12 months.’

The same reviewer went on to explain: ‘Like most of Ferriss' work, it could easily be misunderstood. Be clear that it isn't about shortcuts or 'hacks' — it's about efficiently getting maximum benefit from the minimum input — but that 'minimum input' still requires effort and dedication. You'll get out what you're prepared to put in.’ (That's only *one* person's opinion, of course, but valid points.)

Slow-carb diet risks

There are very few pros to fad, restrictive diets like this one, according to Zeitlin. You can definitely lose weight, but she warns it may not be sustainable for everyone. ‘As soon as you reintroduce the healthy food groups that have been removed, like whole grains and fruits, you will regain weight and likely gain back more weight than you originally lost,’ Zeitlin says.

Zeitlin also warns that you may feel guilty about falling off the plan, and you may end up ‘going overboard’ on the restricted foods if you feel deprived while omitting simple carbs, alcohol, and more six days of the week. ‘Additionally, the concept of a free or "cheat" day can create a messed-up relationship with food, reinforcing the notion that they are 'good' foods and 'bad' foods, when some of those 'bad' foods are vitamin-rich fruits and whole grains,’ she adds.

Is the slow-carb diet safe?

The choice is ultimately yours, and you know your body and personality best. Some people have an easier time losing weight by following structured guidelines and strict shopping lists, while others (like people with a history of disordered eating) may find that type of heavy guidance and rigidity harmful or even downright dangerous.

Zeitlin personally doesn’t recommend trying an overly restrictive diet like the slow-carb diet. ‘Diets that encourage cutting food groups out completely don’t support your health goals long-term and can leave you yo-yo-ing up and down with your weight,’ she says.

If you are trying to lose weight, Zeitlin recommends ‘concentrating on foods you should be adding in versus taking out,’ she says. This includes adding in more veggies, lean proteins, whole grains instead of white flour, and fruits. ‘Keep your grains and fruits to two servings each per day and don’t forget to add in more water, along with sleep and physical activity,’ she says.

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