Pecan-Enriched Diets Alter Cholesterol Profiles and Triglycerides in Adults at Risk for Cardiovascular Disease in a Randomized, Controlled Trial

Abstract

Background Research indicates that tree nuts are cardioprotective, but studies on pecans are limited. Objectives We examined the impact of daily pecan consumption on blood lipids and glycemia in adults at-risk for cardiovascular disease (CVD). Methods This was a randomized, controlled trial where 56 adults (BMI ≥28 kg/m2 or hypercholesterolemia) were randomly allocated into a control group (n = 18) or 1 of 2 pecan groups. The ADD group (n = 16) consumed pecans (68 g) as part of a free-living diet. The SUB group (n = 18) substituted the pecans (68 g) for isocaloric foods from their diet. At baseline and 8 wk, a high-fat meal was consumed with 4-h postprandial blood draws to determine changes in blood lipids and glycemia. Results There was a significant reduction from baseline to 8 wk in fasting total cholesterol (TC) (204 ± 8.76 to 195 ± 8.12; 205 ± 8.06 to 195 ± 6.94 mg/dL), LDL cholesterol (143 ± 8.09 to 129 ± 7.71; 144 ± 6.60 to 135 ± 6.16 mg/dL), triglycerides (TGs) (139 ± 12.1 to 125 ± 14.6; 133 ± 10.7 to 120 ± 10.3 mg/dL), TC/HDL cholesterol ratio (3.92 ± 0.206 to 3.58 ± 0.175; 4.08 ± 0.167 to 3.79 ± 0.151), non–HDL cholesterol (151 ± 8.24 to 140 ± 7.95; 155 ± 6.87 to 143 ± 6.00 mg/dL), and apolipoprotein B (99.1 ± 5.96 to 93.0 ± 5.35; 104 ± 3.43 to 97.1 ± 3.11 mg/dL) in the ADD and SUB groups, respectively (P ≤ 0.05 for all), with no changes in control. There was a reduction in postprandial TGs (P ≤ 0.01) in ADD, and a reduction in postprandial glucose (P < 0.05) in SUB. Conclusions Pecan consumption improves fasting and postprandial blood lipids in CVD at-risk adults. This trial was registered at clinicaltrials.gov as NCT04376632.

Pecan‐enriched diets increase energy expenditure and fat oxidation in adults at‐risk for cardiovascular disease in a randomised, controlled trial

“…However, not all nut studies have shown metabolic improvements because 2.5–6 months of daily almond consumption did not improve markers of energy metabolism 21,22 . Therefore, this preliminary research indicates that tree nuts and peanuts may increase RMR, DIT and fat oxidation, although more research is needed to confirm this notion, particularly in pecans where beneficial effects have been observed on blood lipid profiles but no metabolic research exists 23,24 …”

“…Following anthropometrics, participants then consumed a SFA‐rich, high‐fat breakfast shake within 10 min. This meal provided 17% of total daily energy needs and was made from an original milk chocolate ready‐to‐drink shake (Ensure; Abbott Nutrition) with added fat sources as previously described 24 . The nutrient breakdown of this test meal is provided in Table 1.…”

“…Sixty‐nine sedentary men and women between the ages of 30 and 75 years with high cholesterol or a BMI of ≥ 28 kg m –2 were assessed for eligibility. The inclusion criteria based on ‘high cholesterol’ levels have been described previously 24 . To rule out individuals with familial hypercholesterolaemia, participants with low‐density lipoprotein‐cholestrol levels > 95th percentile or high‐density lipoprotein‐cholestrol levels levels < 20th percentile were excluded.…”

“…The inclusion criteria based on 'high cholesterol' levels have been described previously. 24 To rule out individuals with familial hypercholesterolaemia, participants with low-density lipoprotein-cholestrol levels > 95th percentile or highdensity lipoprotein-cholestrol levels levels < 20th percentile were excluded. Other exclusion criteria included habitual nut consumption (> 2 servings week -1 ), nut allergies, special diets (i.e., ketogenic diet, intermittent fasting), excessive alcohol use (> 3 drinks day -1 for men or > 2 drinks day -1 for women), tobacco or nicotine use, exercise > 3 h week -1 , weight change > 5% of body weight in the past 3 months, history of medical events or medication use affecting digestion, absorption or metabolism, gastrointestinal surgery, and chronic or metabolic diseases.…”

“…21,22 Therefore, this preliminary research indicates that tree nuts and peanuts may increase RMR, DIT and fat oxidation, although more research is needed to confirm this notion, particularly in pecans where beneficial effects have been observed on blood lipid profiles but no metabolic research exists. 23,24 It is also important to note that the two studies with null findings in almonds did not provide any type of dietary instructions to participants, 21,22 whereas the study with peanuts that improved RMR provided instructions regarding substitution of habitual fat calories to accommodate the increased fat intake from the peanuts. 19 Therefore, the type of dietary instructions (or lack thereof) for nut incorporation may be important for inducing beneficial changes in energy metabolism, although no study has directly assessed this.…”