Pros & Cons of a Low-Carb Diet
What are the benefits of a low-carb diet? Learn about the pros and cons to see if a low-carb diet is right for you.
Low-carb diets are all the rage right now! Keto is a huge trend and more people are becoming aware of lower-carb diets. Low-carb diets have been popular for a long time. The high-fat, high-protein, low-carb Atkins diet became popular in the 1990s while the lower-carbohydrate South Beach Diet (which categorized carbohydrates as “good” or “bad”) was a popular fad in the early 2000s.
Lately, the ketogenic diet is the new darling of the diet world. First developed as a treatment for epilepsy, the keto diet is characterized as high-fat, moderate protein, and low-carb. The goal of a ketogenic diet is to get your body into ketosis, a metabolic state where the body burns its own ketones for fuel.
To put it simply, the body needs glucose for fuel and cells get glucose either through readily-available glucose from carbohydrates or through gluconeogenesis. Gluconeogenesis is the process of glucose synthesis from non-carbohydrate sources of fuel such as your own body fat. Through ketosis, you’ll often lose body fat, which is why a keto diet is so popular for weight loss at the moment.
Differences between keto and low-carb
Although these two terms are often used interchangeably, keto and low-carb are two different diets. In general, a keto diet is extremely low-carb. A typical keto diet will get at least 70% of its calories from fat, leaving carbohydrate intake to 10% or less.
Based on this explanation, keto is always low-carb, but low-carb isn’t always keto. A low-carb diet is much more tailored to the individual, and carbohydrate intake may vary.
A low-carb diet can range anywhere from 5% to 50% of your daily food intake, depending on who you ask. The recommended carbohydrate intake for a Standard American Diet is 45-65% of total calories and often is taken up by excess sugar and snack food consumption. For someone on a Paleo diet, 45-65% of calories from carbohydrates is high. For someone on a vegan diet, it may be more moderate.
In general, a low-carb diet is below 45% of your total daily calories from carbohydrates. There’s no official rule for low-carb diets, and it’s best to play around and see what works best for you. It is important to remember that “low-carb” does not automatically equal a healthy diet and does not automatically equate to weight loss.
Learn more about the differences between clean eating, Whole30, paleo, keto, and vegan.
Let’s talk carbohydrates
Carbs are a source of fuel for the body. They are not inherently bad, as you may have been told. Carbs provide your body with glucose which satisfies your body’s energy needs. The body needs a certain amount of glucose to function. Your brain alone requires as much as 60% of your glucose stores.
While your body can make its own glucose via gluconeogenesis, it’s not always optimal and is naturally a more stressful state for your body to exist in. Think about it–gluconeogenesis is used to create glucose when your body isn’t getting any from food. In more primal times, this often was an emergency measure during times of famine.
You may have heard carbs referred to as “good” or “bad” carbs. Refrain from labeling any macronutrient or food as “good” or “bad” as food is just food. There are certain carbohydrates that offer more benefits which we can refer to as healthier carbohydrates.
Food sources of carbohydrates range from simple sugars to complex carbs such as vegetables. You may know already that foods like pasta, bread, and sugary desserts are sources of carbs. But some people forget that vegetables are also carbohydrates–all vegetables, even non-starchy ones like leafy greens.
Healthier sources of carbohydrates include vegetables (starchy and non-starchy), fruit, whole grains, legumes, nuts/seeds, and sweeteners like honey and maple syrup. There’s no need to fear carbohydrate intake from whole foods, as long as your blood sugar remains stable and you don’t have a health condition requiring a low-carb diet.
Disclaimer: always speak to your healthcare provider before making changes to your diet or lifestyle.
There are certain processed carbohydrates that you might wish to stay away from, as they provide little to no nutrition and can spike your blood sugar in an unhealthy way. These include white bread, pasta, refined sugar (and even unrefined sugars in excess!), crackers, flour, and other processed foods. A typical American meal of a hamburger on a white flour bun, a side of French fries, a soda, and a cookie will easily spike your blood sugar cue to excess carbohydrate intake and an absence of nutritional value.
Who might benefit from a low-carb diet?
There are situations in which a low-carb diet is medically therapeutic. Whether it’s ketogenic or not, a low-carb diet has been found to be beneficial in those with the following conditions:
A ketogenic diet has been used as a treatment for epilepsy for nearly a century, as it simulates a state of fasting (recorded as a treatment for epilepsy for over two thousand years!).
Type II diabetes & Insulin resistance
More research is needed for official recommendations, but there is promising evidence that a low-carb diet may be effective for Type II diabetes management, due to the lower levels of insulin in the blood.
Obesity & Pre-diabetes
A low-carb diet is generally beneficial for those with blood sugar regulation issues such as obesity and pre-diabetes (and hyperglycaemia/hypoglycaemia) because blood sugar remains more stable in the absence of high carbohydrate intake. For obese patients, a ketogenic diet may be effective for weight loss in the short term.
Conditions affecting the brain
The ketogenic diet, in particular, is brain protective and can be beneficial for those with various conditions related to brain health such as Parkinson’s, Alzheimer’s, autism and brain cancer. The benefits of this diet are often related to ketone production, so a low-carb diet without ketosis would not provide the same benefits.
Net Carbs vs. Total Carbs
If you’ve ever heard of keto or low-carb diets, chances are that you’ve also heard the term “net carbs.” Net carbs are simply total carbohydrate grams minus total fiber grams. There are different camps within the low-carb diet world that advocate for or against calculating net carbs versus total carbs.
Some argue that net carbs are sufficient when determining carbohydrate intake since the presence of fiber slows down the impact of carbohydrates on your blood sugar. Others argue that this does not impact the amount of insulin required to manage the carbohydrate intake, so calculating net carbs do not matter.
What can you eat?
If you choose to follow a low-carb diet, be sure you’re not unintentionally restricting yourself. A low-carb diet should still contain all three macronutrients and supply you with all micronutrients. Eat a diet rich in the following:
- Animal protein (vegan sources of protein are usually high-carbohydrate as well, so following a vegan/vegetarian low-carbohydrate diet may be unnecessarily restrictive)
- Healthy fats
- Non-starchy vegetables
- Low-glycemic fruit (such as moderate servings of berries)
- Starchy vegetables in moderation (depending on your specific daily carb goal)
Signs a low carb diet is working for you
A low-carb may be the answer that some people are looking for to feel better and manage their weight. If you give a low-carb diet a try, look out for the following signs it’s working for you:
Easy weight loss: if you’re losing weight at a healthy pace after limiting your carbohydrate intake, it may mean your body responds well to the limitation of carbs.
Satiated appetite: you’re restricting carbohydrates, but you feel satiated after meals and have effective hunger cues.
Good sleep quality: you’re sleeping through the night and feel rested upon waking.
Stable energy levels: you feel energetic and don’t experience lags throughout your day.
Signs a low carb diet is not working for you
Just because a low-carb diet is popular right now doesn’t mean it’s the best diet for you. Watch out for the following signs that a low-carb diet is not working for you.
Diminished Workout Recovery: If you’re feeling completely depleted or notice longer-than-normal recovery times after hitting this gym, chances are that you don’t have sufficient glycogen stores to fuel your workout and subsequent muscle repair.
Hungry: If you walk away from meals feeling less than satiated, or your appetite increases, you may need more carbohydrates in your diet.
Mood Swings and Brain Fog: Insufficient carbohydrate intake often leads to insufficient fiber intake. Without fiber to feed them, good gut flora can be crowded out by bad gut flora. Our gut health is directly related to our mental health; your low-carb diet may be harming your gut, and therefore your mood and brain health. Going too low-carb may make you feel restricted and therefore alter your mood.
Sleep Issues: If your glycogen stores are depleted, your liver will not be able to function when it’s most busy–during sleep. Your body may wake you up or keep you from a deeply restful and restorative state if it is looking for glucose.
Hormonal Imbalance: Although there are no large-scale studies on this, most women find that they need carbohydrates for optimal hormone function. Any kind of food restriction or stressful metabolic state (such as gluconeogenesis and ketosis) may signal a lack of safety to your body, therefore causing it to shut off optimal reproductive function. Skipping your period may be a sign that a low-carb diet isn’t for you.
Digestive Issues: Having the right amount of fiber in your diet is crucial for gut health and healthy bowel movements. If you find that you’re not eliminating properly, check that your low-carb diet is still supplying an adequate amount of fiber.
There are certain populations that should absolutely avoid a low-carb diet. Everyone is different, but certain populations require a higher carb intake for optimal health. These populations include:
Pregnant or Breastfeeding Women
Pregnancy and breastfeeding are not times to embark on a potentially stressful diet. It’s better to eat a sufficient amount of carbohydrates for fetal growth, blood sugar regulation, hormonal balance, and milk production.
Unless prescribed and carefully monitored by a doctor, a low-carb diet is not nutritionally sufficient for children. Brain growth is an energy-intensive process that requires sufficient glucose levels. There is no need to restrict a child’s carbohydrate intake unless the diet is medically therapeutic and monitored by a doctor.
Those who do not have weight to lose or who need to gain weight should avoid restricting an entire macronutrient, especially carbohydrates. Carbohydrate intake is not the only factor in weight gain/loss, but carbohydrate restriction is particularly effective for weight loss. Gaining or maintaining weight on a low-carb diet will be more difficult.
A low-carb diet works for a lot of people, and it may be worth trying. A good way to test a new diet is to commit to it for at least 6 weeks, assuming you don’t develop any troublesome symptoms related to restricting carbs. Always check with your healthcare provider before starting a new diet to make sure it’s appropriate for you.
I’m reviewing all of the trendy diets. Read more about the various options to help decide what is best for you:
- Fertility Diet
- Gluten-Free & Dairy-Free Diet
- Intermittent Fasting
- Low-Histamine Diet
- Keto Diet
- Paleo Diet
- Low-Sugar Diet
Note: this post is for informational purposes only and is not intended as medical advice. Please consult your healthcare provider for recommendations related to your individual situation.