The Effects of Eight Weeks’ Very Low-Calorie Ketogenic Diet (VLCKD) on Liver Health in Subjects Affected by Overweight and Obesity

Abstract

Very low-calorie ketogenic diets (VLCKD) are widely employed in successful weight-loss strategies. Herein, we evaluated the efficacy and safety of a VLCKD on non-alcoholic fatty liver disease (NAFLD) and parameters commonly associated with this condition in overweight and obese subjects who did not take any drugs. This prospective, real-life study included thirty-three participants who followed a VLCKD for 8 weeks. NAFLD was diagnosed using transient elastography (FibroScan). Data on anthropometric measurements, bioimpedance analysis, and biochemical assays were gathered both before and after the dietary intervention. BMI (kg/m2) (from 33.84 ± 6.55 to 30.89 ± 6.38, p < 0.01), waist circumference (cm) (from 106.67 ± 15.51 to 98.64 ± 16.21, p < 0.01), and fat mass (Kg) (from 38.47 ± 12.59 to 30.98 ± 12.39, p < 0.01) were significantly lower after VLCKD. CAP (db/m), the FibroScan parameter quantifying fatty liver accumulation, showed a significant reduction after VLCKD (from 266.61 ± 67.96 to 223 ± 64.19, p < 0.01). After VLCKD, the fatty liver index (FLI), a benchmark of steatosis, also revealed a significant decline (from 62.82 ± 27.46 to 44.09 ± 31.24, p < 0.01). Moreover, fasting blood glucose, insulin, triglycerides, total cholesterol, LDL-cholesterol, ALT, γGT, and FT3 blood concentrations, as well as insulin resistance (quantified by HOMAIR) and systolic and diastolic blood pressure levels, were significantly lower after VLCKD (p < 0.01 for all the parameters). By contrast, HDL-cholesterol, 25 (OH) vitamin D, and FT4 blood concentrations were higher after VLCKD (p < 0.01 for all parameters). The variation (δ) of CAP after VLCKD did not show a correlation with the δ of any other parameter investigated in this study. We conclude that VLCKD is a helpful approach for NAFLD independent of changes in factors commonly associated with NAFLD (obesity, fat mass, insulin resistance, lipids, and blood pressure) as well as vitamin D and thyroid hormone levels.

The Effect of a Low-Carbohydrate High-Fat Diet on Laboratory Parameters in Women with Lipedema in Comparison to Overweight/Obese Women

“…It is promising to see that the LCHF diet did not have a negative impact on liver function and even showed slight improvements in liver parameters. The results of this study are consistent with other studies, such as those conducted by Cunha et al [31], D'Abbondanza et al [21], and Rinaldi et al [32], which suggest that a very-low-carbohydrate high-fat diet may be beneficial for patients with NAFLD. The metabolic shift from carbohydrates to triglycerides as the main energy source may contribute to the reduction in liver fat accumulation, especially in overweight/obese patients with increased visceral adipose tissue.…”

“…However, the observed decrease was not clinically relevant. The study conducted by Rinaldi et al [32] showed similar results regarding to TSH after 8 weeks of VLCKD. It is important to note that changes in TSH levels should always be interpreted in the context of thyroid function and individual patient characteristics.…”

“…Our results are not in line with those, and we demonstrated a lack of change in uric acid concentrations in both study groups. Rinaldi et al [32] did not observe changes in the concentration of uric acid after 8 weeks of VLCKD on NAFLD in the overweight/obese patients. It is important to note that individual responses to dietary interventions can vary, and there may be several factors that influence changes in uric acid concentrations, including genetics, medication use, and other lifestyle factors.…”

The Ketogenic Diet and Cardiovascular Diseases

“…Another study from 2023 also indicated that VLCKD was effective in reducing blood pressure in patients with non-alcoholic fatty liver disease (NAFLD) over an 8-week period. There was a reduction in the mean systolic blood pressure from 133.51 ± 12.86 mmHg to 123.27 ± 10.51 mmHg and the diastolic blood pressure from 81.73 ± 8.09 mmHg to 75.27 ± 7.84 mmHg [207]. In a 2022 randomized controlled trial, the ketogenic diet together with continuous positive airway pressure (CPAP) reduced systolic and diastolic blood pressure values to a greater extent (from 142.8 ± 13.…”

Preventive effect of low-carbohydrate high-fat dietary pattern on liver disease caused by alcohol consumption via a 6pgd-involved mechanism in mice

“…Some extremely low-carbohydrate dietary patterns with a 10% or less carbohydrate calorie proportion, termed the ketogenic diet, have been shown to improve fatty liver. 16,17 Recently, clinical randomized controlled trials revealed that a low-carbohydrate high-fat (LCHF)-diet pattern (20%-26% energy from carbohydrates and 50%-60% energy from fats) is effective in improving hepatic steatosis and insulin resistance, which are the common pathological features in ALD. 16,18 In experimental animals, LCHF-diet has been shown to ameliorate cognitive impairment and neuroinflammation, 19 inhibit cardiac hypertrophy, 20 as well as reverse HF-diet-induced hepatic lipid accumulation and insulin sensitivity reduction in mice.…”