Consuming a hypocaloric high fat low carbohydrate diet for 12 weeks lowers C-reactive protein, and raises serum adiponectin and high density lipoprotein-cholesterol in obese subjects

Abstract

Objective High fat, low carbohydrate (HFLC) diets have become popular tools for weight management. We sought to determine the effects of a HFLC diet compared to a low fat high carbohydrate (LFHC) diet on the change in weight loss, cardiovascular risk factors and inflammation in subjects with obesity. Methods Obese subjects (29.0–44.6 kg/m2) recruited from Boston Medical Center were randomized to a hypocaloric LFHC (n=26) or HFLC (n=29) diet for 12 weeks. Results The age range of subjects was 21–62 years. As a percentage of daily calories, the HFLC group consumed 33.5% protein, 56.0% fat and 9.6% carbohydrate and the LFHC group consumed 22.0% protein, 25.0% fat and 55.7% carbohydrate. The change in percent body weight, lean and fat mass, blood pressure, flow mediated dilation, hip:waist ratio, hemoglobin A1C, fasting insulin and glucose, and glucose and insulin response to a 2 h oral glucose tolerance test did not differ (P>0.05) between diets after 12 weeks. The HFLC group had greater mean decreases in serum triglyceride (P=0.07), and hs-CRP (P=0.03), and greater mean increases in HDL cholesterol (P=0.004), and total adiponectin (P=0.045) relative to the LFHC. Secreted adipose tissue adiponectin or TNF-α did not differ after weight loss for either diet. Conclusions Relative to the LFHC group, the HFLC group had greater improvements in blood lipids and systemic inflammation with similar changes in body weight and composition. This small-scale study suggests that HFLC diets may be more beneficial to cardiovascular health and inflammation in free-living obese adults compared to LFHC diets.

C-reactive protein is increased in schizophrenia but is not altered by antipsychotics: meta-analysis and implications

“…High-sensitivity CRP is the most sensitive assay for assessing CRP levels. 12 Usually, in apparently healthy subjects, CRP levels are lower than 3 mg l − 1 , but slightly increased levels can occur in normal individuals. These indicate a state of low-grade inflammation, which is frequently associated with obesity and metabolic syndrome, and predicts an increased risk of depression 13 and cardiovascular diseasescommon comorbidities in persons with SZ.…”

Effects of Dietary Macronutrients on Plasma Lipid Levels and the Consequence for Cardiovascular Disease

“…For example, even though subjects who followed a restricted carbohydrate diet started to regain weight after 6 months, the residual effects of carbohydrate restriction on blood lipids (HDL and triglycerides) levels were detectable for up to 2 years [15]. Another study that compared the effects of dietary macronutrient content (3.5% protein, 56.0% fat and 9.6% carbohydrate versus 22.0% protein, 25.0% fat and 55.7% carbohydrate) found that the high fat/low carbohydrate diet resulted in greater improvements in blood lipids and systemic inflammation when compared to the low fat/high carbohydrate, even though there were no detectable differences in body weight between the two diets [21].…”

“…Additionally, a 12-week diet of high-fat, low-carbohydrate content (60% fat, 35% protein, and 40 g/day carbohydrates) led to greater improvements in blood lipid profiles by decreasing TG levels and increasing HDL cholesterol in comparison to a low-fat, high-carbohydrate diet (25% fat, 15% protein, and 60% carbohydrates; [21], which is in agreement with past work [14,15]. Conversely, additional groups have also reported increased levels of LDL cholesterol following low-carbohydrate and high-fat diets [16,22], whereas others reported initial increases in LDL cholesterol in individuals following diets low in carbohydrate content when compared to those following diets low in fat content, but there were no significant differences after 6 and 12 months follow-up [27].…”

“…For example, even though subjects who followed a restricted carbohydrate diet started to regain weight after 6 months, the residual effects of carbohydrate restriction on blood lipids (HDL and triglycerides) levels were detectable for up to 2 years [15]. Another study that compared the effects of dietary macronutrient content (3.5% protein, 56.0% fat and 9.6% carbohydrate versus 22.0% protein, 25.0% fat and 55.7% carbohydrate) found that the high fat/low carbohydrate diet resulted in greater improvements in blood lipids and systemic inflammation when compared to the low fat/high carbohydrate, even though there were no detectable differences in body weight between the two diets [21].Many reports have found beneficial effects of low-fat diets on blood lipid profiles: a recent meta-analysis that included 32 studies, with follow-ups of 12 months or more, found that low-fat diets, where fat intake accounted for 30% or less of total energy, had significantly greater long-term (12 months) reductions in LDL cholesterol compared to high-fat diets, where fat intake accounted for more than 30% of total energy [22]. Other low-fat diets, including Dietary Approaches to Stop Hypertension (DASH)-style diets, which are promoted by the National Heart, Lung, and Blood Institute, have similarly been found to lower risk of stroke and coronary heart disease [23], and to significantly lower levels of total, LDL, and HDL cholesterol compared to control diets (approximately 50% of energy intake from carbohydrates, 37% from fat, and 14% from protein); [24] and regular, unmonitored diets [25].…”

Impact of high-fat, low-carbohydrate diet on myocardial substrate oxidation, insulin sensitivity, and cardiac function after ischemia-reperfusion

“…The effect of such diets on cardiovascular health has been the subject of intense investigation. Population studies evaluating the impact of HFLCD on cardiovascular clinical outcomes have provided a range of results, with some finding favorable changes in cardiovascular disease risk factors (9,35,37), and others showing an increased risk of adverse outcomes in both animal (29) and human studies, including in the setting of myocardial infarction (23). Consistent with this latter finding, we have previously demonstrated that HFLCD (when eaten prior to experimental infarction) induced lower recovery of cardiac function, larger infarct size, and increased risk of death by pump failure and ventricular arrhythmias following coronary ligation myocardial ischemia-reperfusion (25).…”