Low-carb enthusiasts will say that cutting carbs is the key for weight-loss. However, nutrition research consistently shows that carbohydrates don’t make you gain weight. Despite the argument that raised insulin with carbohydrate consumption should drive weight-gain, and that a low carb diet increases metabolism or fat loss, the latest clinical trail does not support that. For the specific study, please see the link in my reference (1).
Caloric intake, macronutrient breakdowns and exercise were all controlled in the study. Participants, regardless of low carb or high carb diet, when on calorically restricted diets, lost 1.1 lbs/week.
Switching to a low-carb diet did cause an initial sharp drop in weight, but that was due to the drop in water-weight that comes with carbohydrate-restriction (2).
Although the low carb diet did increase metabolism by 57 calories per day, the metabolic advantage disappeared after several weeks. This is if diet composition is at 5% carbohydrates, which isn’t worth it, nor sustainable long-term. Additionally, according to other studies, the low carb diet reported to contribute to low energy levels and mood swings (1).
What about high fat vs. high carb diets? Which can cause more weight-gain? Well, according to another study (3), both carbohydrate and fat over-feeding in the same amount of calories caused an equal amount of increased in weight-gain. This increase also showed no difference between lean and obese individuals.
But what about all the people who go on a “low-carb” diet and report success? If we look at their diets, often the shift to low carbohydrate diet is combined with a cut in calories overall and increased exercise, both contributing to weight-loss, not the low-carb diet per se. This is not to say that a diet high in refined and excessive amounts of carbohydrates is recommended. What is suggested is a diet that incorporates complex carbohydrates such as whole grains, dairy (if you can tolerate it), and fruits and vegetables in the right proportions combined with lean proteins. Of course everyone is different as certain people with Celiac Disease, for example, would need to avoid gluten but that is very individual-specific. If you would like an individual assessment and recommendations based on your own medical history and dietary needs, contact me and I will be more than happy to help you. Note that certain insurance companies will cover Registered Dietitian services! Contact your insurance provider to confirm your coverage.
- Link: https://academic.oup.com/ajcn/article/104/2/324/4564649
- Link: https://www.ncbi.nlm.nih.gov/pubmed/1615908
- Link: https://www.ncbi.nlm.nih.gov/pubmed/26278052