Low Carb… No Carb… Some Carb… It’s all a BIG Question!
Ohhh, carbohydrates! Love them, hate them, limit them, or devour them… we all know carbs and have seen their impact on our glucose levels. There are many joys in life- I would consider carbs to be one of them and beyond that, mastering a bolus for your favorite carb-containing food can feel like a whole next level!
There are many different schools of thought about how to approach carbohydrates and a certain amount of “carbohydrate consciousness” that diabetes brings to our lives. This consciousness can be a good thing in helping to fine-tune carbohydrate estimation skills, but when taken too far carb consciousness can domineer as an overly restrictive lifestyle that creates an unbalanced eating pattern. The American Diabetes Association suggests that there is no one single diet for managing diabetes, but affirms that reducing overall carb intake is a viable strategy to improve glucose levels when the eating plan is personalized for the individual.
The trouble? Carbs are often demonized and oversimplified as the quick fix (and only fix) to weight loss and improved glucose. Most of us who estimate carbohydrate content regularly realize that carbs encompass a much wider variety of foods than just the processed foods, snacks, and sweets that are commonly targeted as “bad” carbs in health-related media. Removing processed, refined, and sugary foods is considered best for everyone’s health (diabetes or not). I make this point because low-carb eating patterns get credit for eliminating foods like these, while truly all eating patterns should! Prioritizing healthful, nutrient-dense food choices is the best way to promote and protect overall health for a lifetime!
Selecting a carbohydrate philosophy can be confusing and keeping up with the low carb lingo, even more perplexing. What is considered “low carb” to one person may in fact be quite a bit of carbohydrate for someone else. The sheer variety of diversity in defining “low carb” and “keto” (even in nutrition research) is impressive. Before we get to talking about the pros and cons of low-carb eating, let’s outline what we mean when we talk about low-carb eating approaches.
Check out the chart below to compare some of the differences in low carbohydrate eating styles, ranked most restrictive on top to least restrictive on the bottom.
Differences in low carbohydrate eating styles
Name | Description | Carbohydrates per DAY | Carbohydrates per MEAL* |
| Ketogenic | High-fat, extremely low carb diet that provides roughly 90% of energy from fat. This eating pattern was developed to control seizures in some people with epilepsy but has recently been popularized for weight loss and blood glucose control given the ability to induce nutritional ketosis. Requires significant food group restrictions for all categories other than fats and often requires regimented measuring/weighing of carbohydrate and non-carbohydrate foods, monitoring of ketones. | ~ 20 grams | <7 grams |
| Very Low Carb | Restricted carbohydrate eating pattern which allows greater carbohydrate variety though this approach still intends to achieve nutritional ketosis (not the same as diabetic ketoacidosis). Carbs are minimized at all meals and snacks. This very low carb pattern is commonly considered as mainstream “keto” but often does not require as stringent monitoring as a traditional ketogenic diet for those managing epileptic seizures. | 20-50 grams | 6-16 grams |
Low Carb | Carbohydrate eating pattern that reduces carbohydrate intake at meals though still includes carbohydrates overall. This approach meets the brain’s daily requirement for glucose provided exclusively by carbohydrates (and does not rely on other metabolic processes for the provision of energy to the brain). Traditionally excludes refined/processed carbohydrates and sweets but does not limit other sources of carbohydrate such as dairy, vegetables, whole grains, and fruits. | 130 grams | <43 grams |
| Moderate/Reduced Carb | Moderate carbohydrate intake pattern which is least restrictive and includes foods from all food groups, but represents a significant decrease in carbohydrate from an unrestricted diet or usual intake. Typically restricts refined/processed carbohydrates and sweets though these can be included in moderation. | 131-225 grams | 45-75 grams |
| Low Glycemic | Eating approach which emphasizes the quality and type of carbohydrate based on the impact of carbohydrate on blood glucose level. Does not restrict food groups or total amount of carbohydrate in the diet. Instead encourages intake of foods with lower glycemic index ratings (0-100)- the lower the GI score, the better. | n/a | n/a |
| Normal diet | Unrestricted carbohydrate eating pattern where approximately 50-60% of daily energy intake is derived from carbohydrate. | n/a | n/a |
*Assumes 3 meals per day.
Here, you find that Ketogenic and very low carbohydrate diets contain the least carbohydrate and are most restrictive. The low carbohydrate and moderate carbohydrate eating styles still limit carbohydrate intake, but to a lesser degree. Finally, unrestricted “normal” eating patterns tend to have about half a person’s daily energy provided by carbohydrates. As you can see, at mealtimes low carb eating ranges from less than 7 to more than 75 grams of carbohydrate per meal (while still being considered low carbohydrate eating)!!
While reducing carbohydrate intake can be very effective for managing both weight, glucose, or reducing bolus insulin doses— a very low carb eating pattern is not the magic bullet for maintaining “non-diabetes” glucose ranges and a healthy weight. Before going full steam ahead with an intensive low carb lifestyle, consider the full picture! Managing glucose is not the only criterion to consider when choosing an eating pattern. Overall health needs to be viewed in a wider lens than just carbohydrate intake and post-meal blood sugar numbers. Let me share a bit of what I’ve learned in my own experimentation with carbohydrate intake…
Low carb eating has had a place in my life for a variety of different reasons and seasons, and I can appreciate the enthusiasm that many have for this eating approach which can be very effective:
- After beginning to use a continuous glucose monitor, I was astounded by the impact that some of my usual food choices and standard bolus approaches had on my glucose values. I began to slowly reduce my carbohydrate intake and experiment with lower glycemic food choices and advanced bolus strategies, both of which worked remarkably well to manage my post-meal glucose spikes!
- The timing of this carbohydrate experimentation aligned with my training to become a dietitian, and as I learned and applied the principles of healthy eating along with smart carbohydrate choices, I found a balance of eating a variety of foods while still being able to achieve the glucose targets that were important to me.
- When Celiac Disease was added to my list of diagnoses, I gravitated to lower carb options on menus and meal plans as this was an easy and natural way to completely eliminate gluten from my diet (medically required for management of gluten intolerance/Celiac Disease).
- When my career previously required frequent overnight international travel and flights, finding low carb options in airports, restaurants, and hotels was often easier than finding reliable gluten-free carbohydrates.
- A lower glycemic plan was also a winning one as I prepared for tight glucose control prior to pregnancy and needed an optimal mix of high nutrient choices that minimized glucose peaks and provided enough carbohydrate.
Minimizing carbs certainly has an impact on flattening your CGM graph, but striving for a constant straight line can become an all-consuming job without blockbuster results in overall health. The carbohydrate goals I have used have changed throughout the years to fit the different needs of my health, and the ability to have flexibility in dialing up and down my carb intake has been a helpful strategy (not the only one) in managing my glucose levels, weight, and health. Constantly measuring diabetes management success only by the flatness of your CGM line is not a winning, lifelong strategy. In present day, diabetes is a life-long marathon so choosing a strategy that works for a lifetime is more valuable than a strategy that is only focused on your performance on one of the 26 miles of the marathon.
The actual decision to eat a very low carbohydrate eating pattern can distort the way we perceive the role of carbohydrates in our diet, and striking a balance is always a concern for those of us in the field of nutrition. Becoming hyper-focused or even obsessed with a perfect and flat sensor line is not psychologically healthy or physiologically reasonable for those of us with Type 1. There are many people who choose keto eating styles successfully and are highly satisfied in their choice, and remember, current nutrition guidance suggests that carbohydrate intake is a viable strategy to improve glucose levels. However, it’s important to caution against selecting an extremely rigid or strict eating pattern for children or anyone who is unable to select for themselves. Simply speaking, carbohydrates are needed for healthy growth in children.
Extremely low carb eating patterns are restrictive and difficult to maintain long-term, may cause the feeling of fogginess or reduced overall energy, create fluid shifts in the body which mask weight loss, interfere with achieving healthy growth in children, and make eating more difficult than necessary in most social settings. Before tossing out every carbohydrate, consider both the pros and the cons.
Pros and Cons of Low-Carb Eating | |
| PROS | CONS |
| Improved weight | Difficult to maintain |
| Improved glucose control (A1c reduction) | Fad diet mentality vs lifelong healthy eating mindset |
| Improved HDL cholesterol | Cause brain fogginess or fatigue during ramp up |
| Improved Blood Pressure | Weight loss may be related to fluid shifts and not caloric deficit |
| Reduction of processed foods and low nutrient density food choices | Interfere with healthy growth in children |
| Reduction of carbohydrate estimation errors | Difficulty eating in social settings |
| Elimination of sugar-sweetened beverages, low-nutrient density foods and snacks | No positive impact on LDL cholesterol, triglycerides, cardiovascular disease, or diabetes prevention |
| Can include more healthful choices such as non-starchy vegetables and lean protein (though not all low carb eating styles do) | Overemphasis on animal protein sources |
| Promotes normal metabolism where glucose is fuel source | Weight re-gain when carbohydrates are reintroduced |
| Long-term safety needs further research | |
If you’ve been following a low-carb approach, be on the lookout for some of these warning signs to re-consider if this eating pattern is best for you. If you are experiencing any of the following, it may be time to revisit your eating plan!
- Carb Judging: The feeling of food hyper-awareness that presents when one discovers the higher carbohydrate content of a food or portion that another person has self-selected.
- Carb Guilt: The feeling of shame when consuming a carbohydrate-rich or high glycemic food while anticipating a post-meal blood glucose spike.
- Carb Shaming: The act of providing negative commentary regarding another person’s decision around carbohydrate consumption, selection, or intake.
- Carb Policing: Controlling another person’s carbohydrate intake to provide a desired outcome on glucose or weight without their informed consent or agreement.
- Carb Tunnel Vision: The state of becoming so focused on carbohydrate counting that one loses sight of creating a nutritionally balanced intake that includes foods from all food groups. During the act of eating, one may experience visually seeing food, but only consciously “see” the grams of carbohydrate present, not the actual foods or portions.
In conclusion, there are many factors to choosing a low carb lifestyle. To decide what is best for you (or your child): be balanced to get the most out of enjoying food and achieving your glucose/weight goals for the best long-term picture of health.
Sarah is the Director of Nutrition Education at Integrated Diabetes Services. As a diabetes care and education specialist and registered dietitian nutritionist, she provides online coaching to clients across the globe seeking to improve their nutrition, diabetes, and weight. She has been living with type 1 diabetes for more than 20 years and is dedicated to sharing insights from her personal journey with others who are navigating Type 1 diabetes.
Thanks Sarah. You did a good job differentiating the different types of carb diets. I also appreciated that you included the potential psychological impact and pitfalls (i.e. carb shaming etc).