Low Carb Diet: Foods to Eat for Weight Loss

Curious about cutting carbs? Many people attempt a low-carb diet as a means of losing weight. The concept isn’t one-size-fits-all and can apply to a multitude of professionally designed diet plans as well as individual eating habits. Reducing carb intake may have benefits for weight loss and blood sugar management for some people. But it can have negatives like nutrient deficiencies and low energy too.

Here’s what to know about low-carb diets.

A low-carb diet is an umbrella term for several eating patterns that restrict carbohydrate intake. Because the term encompasses a range of diets, there’s no one specific guideline to follow — or carb threshold to stay under.

“Low-carb actually has no formal definition,” explains Lauren Twigge, a registered dietitian based in Dallas. “What is high for some individuals on a low carbohydrate could fall well within a well-balanced meal for others.”

The current recommended daily carb intake, set by the National Institute of Medicine in 2002, is 45% to 65% of calories. A low-carb diet could be any eating pattern where a person eats less than those recommended values, with some diet plans promoting around 26% or fewer calories from carbs, or 130 grams of carbs a day.

With a nuance of individual needs, Twigge adds that “it is difficult and potentially dangerous to set a recommended number of carbohydrates for every single person.”

“People have such different caloric needs throughout the day,” she says. “There is no one-size-fits-all recommendation for a low-carbohydrate diet. Instead, adjusting your carbohydrate intake to contribute a lower percentage of your daily calorie intake could be a better option.”

To measure carb intake, it’s first important to establish your goals – or what percentage of your diet you are devoting to carb consumption, Twigge says. From there, you can familiarize yourself with what foods are carb-dominant – or, contain a high percentage of calories from carbs – and read nutrition labels.

Carb intake will be listed in the “total carbohydrate” line of the label. Most foods contain more than one macronutrient (which includes carbohydrates, proteins and fats) but can be higher in one than another. For example, whole wheat bread is considered a carbohydrate, but provides some amounts of proteins too. Whole wheat bread also contains several beneficial vitamins and minerals.

“Using the food label also allows you to focus on choosing high-fiber carbohydrates and ones that are packaged up with other nutrients,” Twigge says.

If you’re on a diet that calls for 130 grams of carbs per day, you might want to aim for about 10 grams of carbs per snack or 30 to 40 grams of carbs per meal, Twigge adds. However, needs will vary person to person.

Low-carb diets can be effective for weight loss for a few reasons. Some of these include:

Low-carb diets may have benefits for cardiovascular health, including lowering triglyceride levels. Triglycerides are a type of fat found in the blood. The body converts unused calories into triglycerides and stores them to be used as energy later. Reducing the number of carbs you eat can reduce the likelihood that unused carbs will be converted into triglycerides.

Reducing the number of carbs you eat may also help the body burn fat. If we don’t eat carbohydrates, which are our body’s preferred source of energy, we will run out of glycogen – a stored sugar that can be used as fuel. Without enough glycogen, our bodies look for other sources of fuel, starting with fat stores, or those triglycerides.

This can also impact insulin resistance and improve insulin levels. Gabrielle N. Gambino, a registered dietitian at NewYork-Presbyterian/Weill Cornell Medical Center in New York City, explains that insulin is a hormone that supports our bodies’ mechanism for fat storage.

“Some studies have shown a short-term reduction in triglyceride levels, which are a main indicator of heart disease risk, yet other cardiovascular disease markers such as total cholesterol were unchanged after following a low carb, in comparison to other diets,” Gambino adds.

Carbs vary in glycemic index, or GI, which is a scale to measure how quickly and how high a food increases blood sugar levels on a scale of 0 to 100. Pure sugar, or glucose, has a GI of 100. Refined starches also have high GIs.

Eating too many high-glycemic foods comes with health risks, as surges in blood sugar can be dangerous for people with diabetes, and can put others at risk for developing conditions like diabetes. Further, low-GI carbs are digested slower and can help you stay fuller longer, reducing the need for overeating.

However, high-GI foods aren’t inherently bad and not everyone needs to exclude them from their diet. Sometimes, paying attention to the GI of a food simply incentivizes people to consume more fiber and produce. Especially if your diet is rich in whole foods and devoid of processed foods already, adding a high-glycemic banana or sweet potato is unlikely to have a negative impact on your health. For example, brown rice consumed with lean protein and non-starchy vegetables will have less of a glycemic impact than brown rice consumed by itself.

When you cut fat or calories, you also usually slash your carb intake, and vice-versa.

“Creating a calorie deficit is an essential component of weight loss,” Twigge says. “Carbohydrates tend to be the easiest macronutrient to overeat, and this can cause people to eat above their daily calorie needs, leading to weight gain.”

“When individuals lower their carbohydrate intake or begin to follow a low-carbohydrate diet, they are often removing many of the foods that they may have been overeating.” When this happens, she adds, the next step can be weight loss.

However, calorie reduction is a primary mechanism for weight loss in many diets – not only those that are low in carbs. So, while low-carb diets can promote weight loss, the composition of macronutrients might not deserve all the credit.

For example, some studies on dieting have found that low-carb diets, moderate-carbohydrate diets and low-fat diets all incur similar levels of weight loss..

Melanie Murphy Richter, a registered dietitian nutritionist based in the Los Angeles area and instructor of nutrition physiology at the University of California–Irvine, says that “due to the nature of our food supply, most of our processed foods are extremely high in added sugar.”

Added sugar refers to sugar that has been slipped into a food product for flavor or shelf stability purposes. And like sugar of all varieties, added sugar is a carb.

“When the average person avoids carbohydrates, this severely limits their consumption of processed foods that are high in added sugar,” Richter says. “This means they are quickly eliminating many excess calories each day, which results in quick weight loss.”

Carbohydrates are the body’s primary source of energy and can be found in many nutritious and good-tasting foods – so following a low-carb diet may turn you into a bit of a picky eater. The good news is that there are several foods that are low in carbs, if not void of carbs altogether. Being extra vigilant of your food’s nutritional makeup can help you know what to eat and avoid.

Robin Foroutan, an integrative dietitian nutritionist based in New York City and a spokesperson at the Academy of Nutrition and Dietetics, says she utilizes and recommends low-carbohydrate diets in her practice all the time. If assisting a client in following this sort of meal plan, she likes to give them suggestions of foods they can eat first, to jumpstart their journey.

Foroutan says that fruits like berries, kiwi, apple and grapefruit fit well with low-carb meal plans, as they are “high in antioxidants and lower in sugar than many other fruits.”

Sometimes, when people cut down on carbs, they hyper-focus on increasing protein intake. Increasing protein can be healthy for someone who is protein deficient, but isn’t necessary for everyone. As is, most Americans eat more protein than recommended. The recommended daily allowance, or RDA, for protein is 0.36 grams per pound of body weight.

It’s important to note that these are minimum recommendation numbers. Some studies suggest that the RDA for protein is not sufficient for all individuals and that people with high energy expenditure (like people who exercise frequently) need more protein.

Additionally, some researchers suggest that people over the age of 60 could benefit from an increase to 0.4 or more grams of daily protein per pound. This means that a 60-year-old female who weighs 170 pounds should aim to consume 70 to 84 grams each day. For reference, a 4-ounce cooked chicken breast contains 34 grams of protein, a ½ cup of cottage cheese contains 14 grams and a cup of milk contains 8.

But it’s important not to only focus on protein intake, and to include healthy fats and (some) carbs in a low-carb diet. Overall, foods that have between 0 to 10 grams of carbs per serving can be considered low in carbs, Twigge says.

Several types of fruits and vegetables – like bananas and green peas, for example – are high in carbs. That doesn’t mean those foods aren’t good for you – they are – but if your goal is to eat fewer carbs, you might have to make some sacrifices.

Carbs can also sneak up in unexpected places, Richter says. “Because added sugar is in so many foods like sauces, creams, alcoholic beverages, juices and other similar foods, most people don’t realize how many carbs they are actually eating in foods that aren’t classically considered carbohydrate food.”

Like the term low carb, high carb has a malleable definition per person and per goal. For the most part, foods are considered high in carbs if they contain 30 or more carbohydrates per serving. Most foods have this information available on their nutrition facts label. For foods like unlabeled fruits or vegetables, information is available online.

If milk jumped out to you on this list, you’re not alone. Richter says that milk is, surprisingly, also considered a carbohydrate. She explains that “the more liquid found in a dairy product, the higher the content of carbohydrates.”

When crafting a low-carb meal or snack, Twigge says it’s important to focus on what nutrients you are using to fuel your body – rather than what you are leaving out to deplete it.

“It is essential to not just minimize carbs, but to pair these lower-carb foods with a satiating protein or fat,” Twigge adds. “This will help keep you fuller for longer and not only provide your body with the nutrients it needs but will also make it much easier to stick with a low-carb diet.”

She adds that because many people treat carbohydrates as the base of their meal, she encourages clients following a low-carb diet to “visualize building their plate around non-starchy vegetables instead.”

“How can you have the vegetable become the main part of your plate?” Twigge says she asks clients. A good answer would be: “To have a spinach salad, grilled chicken, oil vinaigrette, chopped pecans and a few diced strawberries for a high-fiber carbohydrate.”

Twigge’s recommendations for building a low-carb plate:

Keeping some carbs, especially those that are high in fiber or whole grain, and keeping carb intake consistent across meals, can also be important in supporting blood sugar levels, she says.

For a low-carb diet to support health – and healthy weight loss – it’s key to replace carbs with other nutritious foods packed with macronutrients, vitamins or minerals. For optimal nutrition, research suggests adding in more plant-based foods and not overdoing it with animal byproducts.

A 2018 study in the journal the Lancet Public Health found that, on average, people who maintained a low-carb diet – defined as getting less than 40% of calories from carbs – were more likely to eat animal fat and animal protein than plant-based fats and proteins.

This group also experienced a higher mortality rate, with findings varying based on the “source of macronutrients,” according to the researchers. They found that “mortality increased when carbohydrates were exchanged for animal-derived fat or protein and mortality decreased when the substitutions were plant-based.”

“We really concluded that it’s not enough to focus on carbohydrates alone, but we really need to consider the types of foods replacing carbohydrates,” says lead study author Dr. Sara Seidelmann, a cardiologist, nutritionist and researcher at Brigham and Women’s Hospital and Harvard Medical School in Boston.

“The reality is that in the U.S. and European populations, eating low-carb is primarily an animal-based endeavor,” Seidelmann says.

When low-carb diets are too high in animal protein and too low in plant-based proteins and fats, some of their health benefits go away, Foroutan says.

There are several different low-carb diets and approaches to low-carb eating. Three well-known ones are the Atkins diet, paleo diet and keto diet. Here are a few low-carb diets:

The Atkins diet is a low-carb diet that prioritizes protein, small amounts of fat and vegetables. Within the Atkins diet are subsets including the Atkins 20 and the Atkins 40. The Atkins 20 is the original Atkins diet, where people start out by eating no more than 20 grams of carbohydrates a day. With the Atkins 40, dieters begin with a maximum of 40 carbs a day. As the diet progresses, carb allowances go up.

The paleo diet is a low-carb diet that features a pre-agriculture revolution menu. People are to avoid processed foods and focus on eating foods like nuts, seeds, lean proteins and vegetables.

The ketogenic, or keto diet, is one of the lowest low-carb diets. It prioritizes foods that are low in carbs but high in protein and fat. It’s been prescribed for decades to treat medical conditions like epilepsy and is used to manage Type 2 diabetes. The keto diet has more recently become popular for weight loss, raising concerns among some health experts. The diet involves getting only about 5% to 10% of a person’s calories from carbs, while the lion’s share – around 70% to 80% – comes from fat and the balance from protein.

“In terms of ketogenic diets (the very-low-carbohydrate diet plans), the long-term effects of this metabolic shift are yet to be completely understood. The body releases calcium stores when in ketosis, which may lead to issues with bone density. Furthermore, excessive protein intake may lead to kidney injury, if prolonged, in certain populations. People living with diabetes need to be careful when lowering their carbohydrate intake significantly, especially those on insulin regimens, (as) improper dosing adjustments could lead to a life-threatening condition called ketoacidosis,” Gambino says.

The Dukan diet is an extremely low-carb diet where users embark on a purely protein meal plan and then slowly add in vegetables and other foods – on some days. The diet is geared toward weight loss.

The OPTAVIA diet is a pre-packaged meal subscription that comes with foods like fatty fish, fruits and some carbohydrates. Dieters can purchase different packages which have varying instructions for meal timing and consistencies.

Eating only refined carbohydrates and sugar can increase your risk for health problems like heart disease and diabetes. But cutting them out entirely can be dangerous too. Further, there’s no consensus on whether a low-carb diet – or any diet – is optimal for weight loss.

“When people remove or severely limit a large number of foods in their diet, there is the potential for an increased risk of nutrient deficiencies,” says Summer Yule, a registered dietitian and health educator based in Avon, Connecticut.

Restricting foods can also lead to disordered eating or unhealthy, abnormal eating behaviors. “If the person thinks that a diet approach may trigger disordered eating behaviors, they should not adopt the strategy,” Yule says.

A low-carb diet can likewise be dangerous for diabetes management. That’s because low-carb diets are extremely restrictive and may not provide dieters with enough nutrients. Further, “low carbohydrate diets tend to lack whole grains, and foods rich in whole grains have high fiber content which are main players in diabetes management,” Gambino says.

What’s more, cutting carbohydrates will “significantly limit our overall fiber intake which is needed for optimal digestion and immune health,” Richter says. “We may feel more tired and lethargic when reducing carbohydrates, as carbs (glucose) is our body’s preferred energy source.”

Carb reduction can also increase the risks of losing muscle mass, put a strain on the kidneys (especially if consuming too much protein instead) and impair the body’s ability to turn on the Krebs cycle, which is the physiological process of turning nutrients from carbs, fats and proteins into energy, she says.

“Without carbohydrates, this cycle will not turn on and will severely impact our ability to create energy to perform everyday tasks,” Richter says.

From preference to personal health needs, there may be several people who should not follow a low-carb diet. Here are a few groups for which the diet could be a bad idea.

People with already low blood sugar could risk even lower levels if they reduce their carb intake, Twigge says. She recommends “not to be too strict when you reduce your carbohydrate intake, continue to eat nutrient-dense sources of carbohydrates, and include similar amounts of carbs at each meal and snack to avoid getting low blood sugar.”

Lowering carbohydrate intake can cause people to miss out on fiber, which supports several mechanisms of the body including digestion and hunger-fullness cues.

Without high enough carb intake, someone may experience brain fog or dizziness – which can be a result of low blood sugar, Twigge says. People who are prone to this should not follow a low-carb diet.

If you experience symptoms after starting a low-carb diet, it is a good idea to grab a high-fiber nutrient-dense carb to snack on, Twigge adds.

People with or at risk for developing eating disorders should also not follow a low-carb diet.

“In general, if a person is healthy, I recommend that people follow the Dietary Guidelines,” Yule says – which does not call for a low-carb diet.

“Always remember that low carb does not mean no carbs,” Twigge says. “You should still aim to focus on including high-fiber carbohydrates like fruit, whole-grain carbohydrates like whole-wheat products and nutrient-dense carbohydrates like those found in dairy milk to ensure you are not missing out on essential nutrients.”

Continuing to eat carbs like whole grains, which are good sources of fiber, minerals and vitamins, can benefit people’s diets, Richter says. “Our carbohydrate needs vary and change depending on our stage of life.”

Gambino says that if patients request low-carbohydrate diets, she suggests “clients try to follow a Mediterranean, low-inflammatory diet in addition to their carbohydrate limits. This means avoiding fried, saturated, animal-based fats like bacon and sausage as much as possible and opting for oils and nuts as mainstay fat sources.”

“I wouldn’t recommend cutting out extensive amounts of carbohydrates unless following a specific diet prescribed to you by a dietitian or other medical professional,” she says.

Health professionals advise tailoring eating plans to fit your body and health goals. It also needs to be sustainable. Input from a registered dietitian – and talking with your doctor if you have any health concerns – can help determine what’s best for you.