A recent study published in JAMA Network Open suggests that the quality of low-carbohydrate diets (LCDs) has a significant impact on weight change among adults in the United States. The study, conducted by researchers from the Harvard T.H. Chan School of Public Health, examined associations between changes in LCD indices and weight change among participants in three different studies: the Nurses’ Health Study (NHS), the Nurses’ Health Study II (NHSII), and the Health Professionals Follow-up Study (HPFS).
Five different LCD indices were analyzed: total LCD (TLCD), animal-based LCD (ALCD), vegetable-based LCD (VLCD), a healthy LCD (HCLD), and an unhealthy LCD (ULCD). The data analyzed included information from 123,332 participants, of which 83.8% were female.
The findings of the study revealed that the mean weight gain over four-year intervals varied between 0.8 kg and 1.8 kg in the HPFS and NHSII, respectively. After adjusting for various factors such as demographics and baseline lifestyle differences, each 1-standard deviation (SD) increase in TLCD score was associated with an additional 0.06 kg of weight gain over the four-year period.
The results also showed that for each 1-SD increase in ALCD and ULCD scores, the corresponding weight increases were 0.13 kg and 0.39 kg, respectively. On the other hand, each 1-SD increase in VLCD and HCLD scores was associated with less weight gain, with reductions of 0.03 kg and 0.36 kg, respectively. These associations were found to be more significant among obese individuals.
In conclusion, the study suggests that the quantity of macronutrients should not be the sole focus in weight management. Instead, the quality of nutrients plays a crucial role in maintaining a healthy body weight. The authors of the study emphasize the importance of considering nutrient quality when making dietary choices.