An article published provides a detailed overview of the nutritional adequacy of three low-carbohydrate diets with differing carbohydrate content.
Study
The study analyzed the nutrient content of two very low-carbohydrate diets and a low-carbohydrate diet, which provided 20, 40, and 100 grams of net carbohydrate per day, respectively. Net carbohydrate refers to the total non-fiber saccharides that are digestible in humans.
The nutrients of public health concern identified in the 2020 Dietary Guidelines for Americans were considered when selecting food items for diet plans. Specifically, these diet plans were designed based on dietary patterns utilized in studies of ketogenic and low-carbohydrate diets as well as commercial low-carbohydrate diets.
Diet plan nutrient content was analyzed using the US Department of Agriculture Food Data Central, which includes five distinct data types that provide information on food and nutrient profiles.
Study Findings
The energy and nutrient analysis of three diet plans indicated that two very low-carbohydrate diets with 20 grams and 40 grams of carbohydrates (VLCD20 and VLCD40) and the low-carbohydrate diet with 100 grams of carbohydrate (LCD100) provide 91%, 94%, and 100% of the RDA for energy, respectively, in females aged 31 – 70 years.
In older females aged 51 – 70, VLCD20 and VLCD40 met the RDA for energy; however, LCD100 provided 12% higher energy than the RDA. In males, none of the diet plans could meet the RDA for energy across all age groups.
In both males and females aged 31 – 70, VLCD20, VLCD40, and LCD100 provided 37, 55, and 98% of the RDA for dietary carbohydrates, respectively. In females aged 31 – 70, VLCD40 and LCD100 provided 9 and 16% higher dietary fiber than the RDA, respectively. However, VLCD20 could not meet the RDA for dietary fiber in this age group.
In older females aged 51 – 70, VLCD20 provided adequate dietary fiber, and VLCD40 and LCD100 exceeded the RDA by more than 20%. In males aged 31 – 70 years, none of the diet plans could meet the RDA for dietary fiber; however, VLCD40 and LCD100 met the requirement in older males aged 51 – 70 years.
All three diet plans provided higher amounts of proteins than the RDA in males and females aged 31 – 70 years. However, the amounts were within the Acceptable Macronutrient Distribution Range of 10–35% of energy.
Regarding saturated fat and sodium, all diet plans slightly exceeded the RDA. However, the study highlights that despite this, the ratio of omega-6 to omega-3 fatty acids was significantly lower than the average American diet, which may offer protective benefits against chronic diseases. The sodium-to-potassium ratio in all three diets was also favorable, remaining well below one, which is considered beneficial for cardiovascular health. This is particularly noteworthy given that most American diets exceed the recommended sodium intake and fall short on potassium, a pattern associated with increased cardiovascular risk.
Conclusion
The study indicates that low-carbohydrate diets intentionally designed to provide lower amounts of carbohydrates than the RDA can deliver adequate amounts of fiber and micronutrients to Americans' diets.
Moreover, the findings suggest that these well-constructed diet plans not only meet but can potentially exceed the nutritional requirements for essential micronutrients in specific populations, particularly females aged 31–50, who are the most likely to follow these diets. This challenges the common perception that low-carbohydrate diets are nutritionally inadequate and underscores the importance of considering dietary quality, not just carbohydrate quantity, in dietary guidelines.
The study also emphasizes the importance of the ratio of omega-6 to omega-3 fatty acids and sodium to potassium provided by the diets, especially for individuals with existing metabolic health issues. These ratios could play a critical role in mitigating the risk of chronic diseases, such as cardiovascular disease, in populations adhering to low-carbohydrate diets.
Source:
https://www.news-medical.net/news/20240905/Low-carb-diets-exceed-nutrient-needs-and-promote-heart-health-by-improving-key-dietary-ratios.aspx