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Aims: Low Carbohydrate High Fat (LCHF) diets are popular for weight loss or glucose control. The main source of energy in such diets is fat but the composition of nutrients varies. This study aims to investigate dietary variations in a real-world LCHF population and its associations with cardiovascular risk factors.

Methods: We recruited 100 volunteers who considered themselves adherent to a LCHF diet. Their last 14 days of dietary intake was assessed using diet history interviews. Validation of energy intake against expenditure was made using activity monitors. Predictive variables for the linear regression models were selected using stepwise bidirectional assessment of Akaike information criterion (AIC).

Results: Energy intake (E%) from carbohydrates was low, 8.7 E%, and fat was the main replacement. Dietary cholesterol was associated with higher total cholesterol, low-density lipoprotein (LDL), and high-density lipoprotein (HDL). Dietary sodium intake was associated with higher blood pressure. Protein intake was associated with lower diastolic blood pressure but also with lower HDL. The intake of dietary fibre was associated with lower LDL and total cholesterol but with higher hemoglobin A1c (HbA1c). The intake of carbohydrates and saturated fatty acids (SFA) was not associated with any of the outcome variables.

Conclusion: In this LCHF population, variations in intake of carbohydrates and saturated fatty acids could not predict any aspects of the cardiovascular risk profile. Lower fibre intake and higher cholesterol and sodium intake predicted a less favorable cardiovascular risk profile.

Background: Low carbohydrate high fat (LCHF) diet has been a popular low carbohydrate diet in Sweden for 15 years. Many people choose LCHF to lose weight or control diabetes, but there are concerns about the effect on long-term cardiovascular risks. There is little data on how a LCHF diet is composed in real-life. The aim of this study was to evaluate the dietary intake in a population with self-reported adherence to a LCHF diet.

Methods: A cross-sectional study of 100 volunteers that considered themselves eating LCHF was conducted. Diet history interviews (DHIs) and physical activity monitoring for validation of the DHIs were performed.

Results: The validation shows acceptable agreement of measured energy expenditure and reported energy intake. Median carbohydrate intake was 8.7 E% and 63% reported carbohydrate intake at potentially ketogenic levels. Median protein intake was 16.9 E%. The main source of energy was dietary fats (72.0 E%). Intake of saturated fat was 32 E% and cholesterol was 700 mg per day, both of which exceeded the recommended upper limits according to nutritional guidelines. Intake of dietary fiber was very low in our population. The use of dietary supplements was high, and it was more common to exceed the recommended upper limits of micronutrients than to have an intake below the lower limits.

Conclusions: Our study indicates that in a well-motivated population, a diet with very low carbohydrate intake can be sustained over time and without apparent risk of deficiencies. High intake of saturated fats and cholesterol as well as low intake of dietary fiber remains a concern.