What Should You Not Eat on a Low Carb Diet?
Max Carmody, MSc
On a low carb diet, there are big yes’s, and big no no’s. So what foods exactly should you try to avoid when going on a fairly standard low carb diet?
When on a low carb diet, you should not eat too much sugar, certain high carb fruits and starchy vegetables, too many starchy foods like pasta and potatoes, too much protein, or too many saturated and trans fats.
Sugar is one of the biggest no no’s on a low carb diet. 1 gram of sugar has 2.3 grams of simple carbs. Although some sources claim that a serving of sugar has up to 28 grams of total carbs. If you’re not on a low carb diet, then a moderate amount of simple sugars are not a bad thing, they can be found in some healthy fruits.
All carbs are eventually broken down into sugars, As sugar levels rise, insulin is released. Insulin moves sugar from the blood to the cells, where it is used for energy. Carbs in some types of foods, like white rice or white flour, are broken down quickly and cause blood sugar to rise quickly.
Increased insulin levels lead to weight gain and fat storage. If your body has too much insulin and too much sugar, your body stores the sugar as fat that doesn’t get burned.
Ultimately, sugar has a very high amount of calories per gram, but it does not make you feel satiated. You are still hungry after consuming it. Even beyond a low carb diet plan, most diets advocate cutting sugars and not having too high of a sugar consumption. If you would like to read an article I have written about what the healthiest way to eat low carb is, you can find it here.
A lot of sugars that people are consuming in their diets are also refined carbs. Refined carbs are sugars and starches that don’t exist in nature. They come from natural foods that have been “processed” to refine them. All sugars, except those that come from a natural whole food like fruits, are refined carbohydrates. Refined carbs are generally frowned upon on low carb diets. This could look like the sugar in a pack of Twinkies, for example.
Avoid Certain Fruits and Vegetables
It might not seem immediately intuitive to have to avoid certain fruits and vegetables on a low carb diet. After all, we are always told to eat more fruits and vegetables. And in general, they are pretty good for you. However, some fruits and vegetables are high in carbs.
Bananas contain a very high amount of carbs, 20 carbs for 100 grams of banana. The average banana is more than 100 grams. Grapes also have very high amounts of carbs, 16 grams of carbs per 100 grams of grapes. If you’re worrying about carbs on your diet and still want to get some healthy fruit in, berries tend to be your best choice. Half a cup of raspberries contains 3 grams of carbs.
You should definitely be eating vegetables as part of a low carb diet. However, be very mindful of the kind of vegetables that you are eating. A basic rule of thumb is that vegetables grown above the ground are less starchy, and those grown below the ground are more starchy, although this is just a rule of thumb and should not be followed 100%.
Starchy vegetables may cause a spike in your blood sugar. Here are some examples of starchy vegetables that you don’t want to eat too much of: corn, white potatoes, sweet potatoes, green peas, acorn squash, butternut squash, turnips, and carrots. If you would like to find out what you SHOULD be eating on a low carb diet, you can find an article here on the subject.
Avoid Starchy Foods
There is no exact definition of “starchy foods”. However, when I say to avoid starchy foods, I mean the bulk of foods not either in the sugar category, or the fruits and vegetables category. This would include foods like bread, pasta, rice, beans, and potatoes.
Starchy foods are our main source of carbs In general, starchy food provide us with a lot of our daily nutrition, and are not necessarily a bad thing. However, if you are specifically trying to follow a low carb diet, then you do not want lots of starchy foods.
Sometimes, starchy foods are called complex carbohydrates. These are necessarily always the exact same thing, but the terms are sometimes used interchangeably. Starchy foods mostly include breads and grains, although they can also include starchy vegetables, and beans. Some starchy grains are “pasta, breads, popcorn, crackers, tortillas, cereals, rice, oatmeal, barley, and millet” Potatoes would be a starchy vegetable.
Whole grains, although generally healthy if you’re on an ordinary diet, are to be avoided on a low carb diet. This would include barley, oatmeal, etc. You should be avoiding “potatoes, potato chips, french fries, corn products and popped corn”. Beans and lentils are a bit of a grey area. They are high in carbs, but also high in protein. On a more extreme low carb diet, you would probably want to avoid these things, but if you are going for more of a moderate carb diet, they may be ok in reasonable amounts as long as you don’t overdo it. If you would like to find out if it is ok to eat cheese on a low carb diet, you can find an article here that I wrote.
Avoiding too Many of the Accepted Food Groups
This is a mistake I have made myself when doing low carb diets. I eat so much protein or fat because it falls into the “accepted” food groups, that I do not lose weight as fast as I should be. Many diets are not actually the protein “free for alls” that people believe them to be. For example, one popular diet, Atkins recommends that people actually eat moderate amounts of protein. Excessive steak, cheese, eggs, and foods like this shouldn’t be overeaten.
Eating too much protein can convert the protein into glucose through a process called gluconeogenesis. Your body stores any excess sugars as fat, through this process. If you do overeat protein foods, you can stall the process into ketosis, or get knocked out of the fat burning stage.
There is an ideal daily amount of protein that you want to be aiming for based on your body weight. You should be eating 1.2 – 1.7 grams of protein for your weight in kilograms, and a kilo is 2.2 pounds.
Fat is generally an accepted food group for low carb diets, but be careful also eating too much saturated fat and trans fat. Saturated fats are found in things like butter, cheese, and red meats. You can have a little, just don’t overdo it.
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