Foods You Should Avoid When On A Low-Carb Diet

What exactly is a low-carb diet? This might seem like an easy question, but there are quite a few low-carb diet plans, each with their own rules and restrictions (via the Mayo Clinic). For example, generally speaking, low-carb diets involve reducing one's carbohydrates intake while increasing fat and protein consumption. But while some low-carb diets are very strict, for instance, about eating grains (which contain carbs), others allow them to some extent.

This can make it confusing to not only figure out what low-carb dieting options are available to you, but also what foods are all right if you're trying to follow one of these low-carb diets. And there's still one more possible complication: Low-carb diets aren't only used for weight loss. Sometimes, a person goes on one to lower their chances of developing other health problems, like type 2 diabetes. This can also impact which low-carb diet one chooses and which foods they either avoid or allow in portion-controlled amounts.

All of this can feel overwhelming, which is why we're going to discuss how certain foods are either off the menu or limited on different diets — both the ones that fit the definition of a strict low-carb diet plan to a tee, and others that are less strict but still get categorized as low-carb. 

Even if you're not that familiar with low-carb diets, you've probably heard of the Atkins diet. As Medical News Today explains, someone following an Atkins meal plan would consume small amounts of carbs while eating however much protein and fat they choose. Like the keto diet, the Atkins diet's goal is to put one's body into a state of ketosis, where their body uses stored fat for energy instead of glucose.

There are different phases of the Atkins diet. Certain foods are generally considered not good for this diet, or can only be eaten during certain phases of the diet (and only in small portions). For instance, in phase 1, someone on the traditional Atkins diet is only supposed to eat 20 grams of carbs on a daily basis. Because of this, starchy vegetables like potatoes are out in favor of low-starch vegetables like the leafy greens used in salads. However, by phase 3, an Atkins dieter can begin adding starchy vegetables back to their meals.

If you are considering the Atkins diet, keep in mind that there are different versions of the diet. For example, if only 20 grams of carbs is too restrictive, you might want to try Atkins 40, which allows the dieter to consumer 40 grams of net carbs per day. However, potatoes and other starchy vegetables are still restricted on this diet.

If you live in Miami, you're probably familiar with South Beach. And, yes, this place is where the South Beach diet gets its name (via the Mayo Clinic). To be clear, this diet isn't a strict low-carb one. In fact, the Mayo Clinic notes that it's "sometimes called a modified low-carbohydrate diet." That said, there is a keto version of it that is more carb-restrictive.

Like other diets on this list, the South Beach diet has different phases, each with their own rules and restrictions. For example, during phase 1, a South Beach dieter isn't supposed to drink any type of alcohol. Interestingly, there was some controversy over whether or not beer should be a no-no beverage on the South Beach diet. As the Chicago Tribune reported back in 2004, Anheuser-Busch Co. stated that maltose — a chemical called "the king of all sugars" in the book "The South Beach Diet" — is changed into alcohol and carbon dioxide during the fermentation process of beer. The book's author, Dr. Arthur Agatston, told the Tribune that most of the maltose is fermented out of beer, but also said that "... beer is fattening."

Additionally, Dr. Thomas Wolever, acting head of the department of nutritional science at the University of Toronto, told the Tribune that a beer can have as many carbs as two teaspoons of sugar, and he notes that low-carb beer is an option "if you're really trying to limit carbs."

MedicineNet puts carrots on the "... foods that you need to avoid" list when it comes to low-carb dieting. As Healthline explains, the Atkins diet, which has four phases, calls for limiting or avoiding eating carrots during phase 1 because they are high-carb vegetables. Carrots aren't as high in carbs as potatoes, for example (via Healthline). However, as the U.S. Department of Agriculture (USDA) points out, a cup of sliced raw carrots does have 9 grams of net carbs. 

This brings us to another low carb diet: the keto diet. According to MedicineNet, the standard keto diet usually means consuming 70% fat, 20% protein, and 10% carbs. Carrots, which basically fall between leafy green vegetables (which are low-carb) and tubers like potatoes (which are higher in carbs than carrots) in terms of carb content, could easily fit into the keto diet. But that doesn't mean you can constantly eat them like Bugs Bunny. In fact, if you're on the keto diet, you'll probably want to keep your carrot consumption to a minimum.

When one thinks of dieting, they might imagine permanently cutting certain foods from their diet. But this isn't the case with the Atkins diet. As the Mayo Clinic explains, Atkins has four phases, and you can even opt to start at phases 2 or 3. However, if you do decide to do all four phases, you'll find that phase 1 is the most restrictive when it comes to carbs. 

The traditional Atkins diet limits carbs to just 20 grams a day during the first phase. As US News & World Report explains, a half-cup of cooked brown rice exceeds that 20-gram limit. In fact, both the Mayo Clinic and US News & World Report note that one really shouldn't start reintroducing whole grains like brown rice until they're at phase 3 of the Atkins diet (the pre-maintenance phase). And even then, if the Atkins dieter finds that they're starting to regain their lost weight, they're advised to start cutting back on their carbs again until they reach their weight loss goal.

While low-carb diets in general can help with weight loss, they can have their downsides. As the Mayo Clinic notes, going low-carb may lead to constipation. And as MedicineNet points out, brown rice is a natural way to help with constipation since it's a whole grain.

The Mediterranean Diet puts the emphasis on plant-based foods, including the primary source of fat for the diet: olive oil (via eMedicineHealth). However, the Mediterranean Diet usually doesn't allow oils that are processed, refined, or hydrogenated.

Hydrogenated oil is when a manufacturer adds hydrogen to certain types of oil, like vegetable oil (per Medical News Today). As a result, the oil becomes solid fat at room temperature, and foods with this hydrogenated ingredient have a longer shelf life. One can find both fully hydrogenated and partially hydrogenated oils on the market. As the American Heart Association explains, partially hydrogenated oils are a major source of trans fats when it comes to processed foods. Trans fats have been shown to raise cholesterol, and might increase one's chances of developing health problems like type 2 diabetes, stroke, and heart disease.

While consuming olive oil is built into the Mediterranean diet and is a good source of antioxidants, you still need to check the food label when choosing a brand of olive oil (via Medical News Today). This is because some olive oils contain refined oil.

While the South Beach diet isn't a strict low-carb diet, it does have certain restrictions. For instance, phase 1 of the diet puts both fruit and fruit juices on the "off-limits" menu (via WebMD). With that said, there are some important details about fruit juice to keep in mind, especially once you reach phase 3 of the South Beach Diet.

According to Healthline, fruit juice and sugar-sweetened soda can contain similar amounts of sugar. Additionally, they have the potential to cause weight gain. Wait, does that mean fruit juice and soda are basically the same when it comes to one's health? Well, no. For one, their potential to cause weight gain is connected to calories and how much of them you drink. Also, drinking portion-controlled amounts of fruit juice might help lower the chances of developing health issues like heart disease and type 2 diabetes. Additionally, as research in Advances in Nutrition points out, fruit juice has nutrients that are usually not in soda.

While fruit juice is typically not allowed during the first phase of the South Beach diet, by phase three, it's up to you to pick not only what foods to eat, but also how much (via WebMD). Just remember to exercise good portion control, and make sure to check a particular juice's Nutrition Facts Label for ingredients like added sugar.

No list of foods that are bad for low-carb diets would be complete without mentioning bread. This is one way that low-carb dieting is notably different from Western diets, which tend to categorizes whole wheat bread as a healthy choice (via Livestrong). Keep in mind, however, that Western diets involve consuming more carbs (sometimes as much as 65%) compared to various low-carb dieting options, per the Mayo Clinic.

If you are used to a Western diet, you might think you can squeeze in a small amount of whole wheat bread on a low-carb diet. Well, let's crunch the numbers. If you're on the standard keto diet and are only consuming 20 net carbs daily, then according to Livestrong, making yourself a sandwich with two slices of whole wheat bread could exceed your carb allowance for the day. If you choose a low-carb diet that allows for more carbs (such as Atkins 40), then technically you could eat that sandwich (per Medical News Today). But just because you can, doesn't necessarily mean you should.

As Livestrong points out, if you use up all your carbs on whole wheat bread, that might mean you're not getting the right amount of fiber. In the case of the sandwich, adding fiber-rich leafy greens can help offset this problem. Remember: You can craft your low-carb diet based on your individual goals and needs.