Low carb diets for weight loss are popular for quick weight loss. However, are low carb diets a viable option for healthy weight loss?
Carbohydrates provide nearly half of the energy that our muscles and body tissue use. However, the question remains: how much carbohydrates are necessary, and are there situations where restricting carbohydrate intake will have a positive effect on a person’s health – especially when considering weight loss?
Low carbohydrate diets have been touted as a great way to lose weight and improve a variety of health problems, such as obesity or Type-2 Diabetes, but that does not necessarily mean that they are the best option.
Keep reading below to learn more!
Should You Use a Low Carb Diet to Lose Weight?
On the surface level, I believe that low carbohydrate diets are and can be effective for weight loss, Type-2 Diabetes, and obesity. An example of this is a controlled study that utilized a very low-calorie diet, approximately 1.5kg per bodyweight intake of protein, and approximately 30 grams of carbohydrates per day.
This is far below the RDA for carbohydrate intake, which is set at 130 grams of carbohydrates per day. Along with the diet itself, the patients of the study were under controlled care, which helped them maintain the diet and the control of the study. After one year, the study diet used showed a reduction in diabetes medication, better glycemic control, and lower weights (Hallberg et al., 2018). The very low carb ketogenic diet has also shown to be able to maintain muscle mass and strength while promoting rapid weight loss (Casanueva et al., 2020).
However, the fact is, this type of diet will likely not fit into the lifestyle of those who it is meant to help the most. Therefore, it is difficult to say it is a viable option. Furthermore, there are still risks of eating a low carbohydrate diet, which would include an increased intake of dietary fat and protein.
In the same study I mentioned before, although there were positive changes, LDL cholesterol increased (Hallberg et al., 2018).
Why Shouldn’t You Use a Low-Carb Diet for Weight Loss?
As I mentioned before, the main concern I have with low carbohydrate diets is that they do not adequately fit the lifestyle of most people. Comparatively, the Mediterranean Diet has also shown to be effective for helping with weight loss and improving glucose control, and it has shown to be sustainable for a lifetime (Bolla, Caretto, Laurenzi, Scavini, & Piemonti, 2019).
For those whose primary goal is rapid, short term weight loss, I believe that the lower end of the Acceptable Macronutrient Distribution Range (AMDR) is a viable option, especially those who are confident with their ability to maintain a specific set of diet parameters. For carbohydrates, the AMDR is 45-65% of daily total nutrient intake. So, I would consider around 40-50% on the lower end.
I also believe this is more viable for those who have sedentary jobs and are not as physically active. Contrarily, I believe those who are more physically active, such as athletes like myself, would benefit from the higher end of the AMDR range for carbohydrate intake. As physical activity or exercise increases, the body relies more on carbohydrates for its predominant fuel source (Murray & Rosenbloom, 2018).
Therefore, I would suggest that the more active a person is, the higher end of the AMDR their carbohydrate intake should be.
Related Reading: Best Complex Carbs for Bodybuilding
But, Is a High Fat Diet Healthy for Weight Loss?
If you are considering a low-carb diet, that means it is likely that you will also be consuming a high protein and high-fat diet as well because if you decrease the amount of carbohydrates you are consuming, you will still need to increase your dietary fat consumption.
The consumption of dietary fats (lipids) is a critical component of any healthy diet strategy; however, the type, quantity, and quality of dietary fat that is consumed is vitally important. Fats are a unique fuel source for the body because, unlike carbohydrates and proteins, fats cannot be converted to glucose.
Although fats are a viable energy source for the body, they cannot easily supply energy to the brain or nervous system, which depends on glucose as a fuel source.
Furthermore, almost all of the excess fat that is consumed by the body is stored as fat, unlike protein and carbohydrates. However, although unhealthy dietary fats (saturated fat and trans fat) has significant negative health implications, eating unsaturated fats provides numerous positives for overall health.
Saturated fats have been linked to increased LDL cholesterol, which is a prominent risk factor for cardiovascular disease.
Furthermore, since dietary fat contains the most calories per gram, and understanding excess dietary fat is easily converted to body fat, a diet high in fat can easily contribute to weight gain due to exceeding energy requirements.
Contrarily, adding unsaturated fats to the diet instead of saturated fats has been shown to reduce LDL cholesterol, therefore lowering the risk of cardiovascular disease. Furthermore, omega-3 fatty acids have shown that they may protect against some cancers through their ability to reduce inflammation in the body, which also reduces other inflammation-based health problems such as asthma.
Regardless, there is little evidence to show that “more is better” for dietary fat consumption. Although unsaturated fats have their health benefits, the focus should be less on adding fat to the diet, compared to replacing saturated fats with unsaturated fats, while maintaining a healthy energy intake and food balance.
Unsaturated fats are an efficient fuel source for the body and should be consumed instead of saturated fats as they reduce the risk of cardiovascular disease and can provide other health benefits for the body when calorie limits are not exceeded.
Interestingly, although individuals consuming a high-fat diet are twice as likely to be obese, eating only “good” dietary fats, such as on the Mediterranean Diet, a high-fat diet can be very healthy. Although the number of calories in “good” fats and “bad” fats are the same, I think this shows that those who eat a high saturated-fat diet are likely also making other poor nutrition choices, such as too much-added sugar or non-nutrient dense foods.
Personally, I think it’s interesting that a high-fat diet can easily result in a high risk for obesity when poor dietary fat choices are made, but can promote heart health and the immune system, as you mentioned, when proper dietary fat choices are made.
Lastly, people on a low-carb high fat diet need to be aware that consuming large amounts of dietary fat supplements, such as fish oil, is not necessarilly a great idea for boosting energy and improving markers of health. Although I do believe fish oil supplements are one of the best supplements for weight loss and muscle gain when you carefully research which supplement to choose, there are risks.
Dietary supplements are not regulated, and it has been shown that fish oil supplements likely do not contain the number of fatty acids and beneficial effects that their label describes (Albert et al., 2015). Furthermore, the processing necessary for Omega-3 fatty acid supplements may even induce lipid oxidization, which would interfere with the potential positive effect of the supplement itself (Mason & Sherratt, 2017).
Although people who use dietary supplements like fish oil may have good intentions, there are certain risks that consumers should be aware of when they are attempting to alter their health outside of the consumption of a healthy diet.
If you are going to eat a high-fat, low carb-diet for weight loss, make sure that you are consuming mostly unsaturated fats from whole foots.
Does it Matter When You Intake Your Carbohydrates?
For those of you who are considering a low carb diet for weight loss, one interesting aspect that deserves additional attention is the timing of carbohydrate intake, and how altering the amount of carbohydrate intake at different points of the day can have a positive or negative effect on blood glucose levels.
For example, delaying breakfast, such as with “time-restricted feeding” (otherwise known as Intermittent Fasting), has shown potential for improving morning glucose tolerance, as well as evening glucose tolerance (Parr et al., 2018).
This is just another example of how you can alter your carbohydrate intake to lose weight and improve your health without actually going on a “low carb diet.”
Concluding Thoughts – Are Low Carb Diets for Weight Loss Healthy and Viable?
There is clearly evidence that suggests that low carb diets can assist with weight loss, but there are many risks associated with these diets. Carbohydrates provide necessary fuel for your entire body, and they provide many valuable nutrients that you cannot get from other foods.
If you would like to try restricting your carbohydrate intake to lose weight, you should first remember that the essence of weight loss is calories in vs calories out. Regarldess of how many carbohydrates you are consuming, if you are in a calorie deficit each day (consuming fewer calories than you are burning) you will lose weight. Therefore, your goal, if you are trying to lose weight, should be to find the type of diet you can maintain that allows you to have a healthy calorie deficit day after day.
Instead of focusing on keeping a very low-calorie diet, I would first suggest using a moderately-low calorie diet (around 40-50% AMDR of carbohydrates per day), while choosing nutrient-dense carbohydrates. I don’t suggest a low carb diet for weight loss mainly because it is difficult to fit into your lifestyle, and it is likely that you will feel depleted and tired.
If you are looking to lose weight, there are a variety of ways to construct your diet. Although a low carb diet can help you lose weight, you should not use the diet solely as a way for quick weight loss, without considering the long-term implications and stability of the diet plan.