- 1Department
of Public Health, Experimental and Forensic Medicine, Endocrinology and
Nutrition Unit, University of Pavia, Azienda di Servizi alla Persona di
Pavia, Pavia 27100, Italy. simoneperna@hotmail.it.
- 2Department of Gastroenterology, Policlinico di Monza, Monza 20097, Italy. attilio.giacosa@policlinicodimonza.it.
- 3Department
of Biomedical Sciences for Health, Division of General Surgery, IRCCS
Policlinico San Donato, University of Milan, Milan 20097, Italy.
bbonit@icloud.com.
- 4Department of Public Health,
Experimental and Forensic Medicine, Endocrinology and Nutrition Unit,
University of Pavia, Azienda di Servizi alla Persona di Pavia, Pavia
27100, Italy. chiara.bologna02@universitadipavia.it.
- 5Department
of Public Health, Experimental and Forensic Medicine, Endocrinology and
Nutrition Unit, University of Pavia, Azienda di Servizi alla Persona di
Pavia, Pavia 27100, Italy. antonio.isu@gmail.com.
- 6Department
of Public Health, Experimental and Forensic Medicine, Biostatistics and
Clinical Epidemiology Unit, University of Pavia, Pavia 27100, Italy.
davide.guido@unipv.it.
- 7Department of Public Health,
Experimental and Forensic Medicine, Endocrinology and Nutrition Unit,
University of Pavia, Azienda di Servizi alla Persona di Pavia, Pavia
27100, Italy. mariangela.rondanelli@unipv.it.
Abstract
Hazelnuts
are rich in monounsaturated fatty acids and antioxidant bioactive
substances: their consumption has been associated with a decreased risk
of cardiovascular disease events. A systematic review and a
meta-analysis was performed to combine the results from several trials
and to estimate the pooled (overall) effect of hazelnuts on blood lipids
and body weight outcomes. Specifically, a Bayesian random effect
meta-analysis of mean differences of Δ-changes from baseline across
treatment (MDΔ) (i.e., hazelnut-enriched diet vs. control diet) has been
conducted. Nine studies representing 425 participants were included in
the analysis. The intervention diet lasted 28-84 days with a dosage of
hazelnuts ranging from 29 to 69 g/day. Out of nine studies, three
randomized studies have been meta-analyzed showing a significant
reduction in low-density lipoprotein (LDL) cholesterol (pooled MDΔ =
-0.150 mmol/L; 95% highest posterior density interval (95%HPD) = -0.308;
-0.003) in favor of a hazelnut-enriched diet. Total cholesterol showed a
marked trend toward a decrease (pooled MDΔ = -0.127 mmol/L; 95%HPD =
-0.284; 0.014) and high-density lipoprotein (HDL) cholesterol remained
substantially stable (pooled MDΔ = 0.002 mmol/L; 95%HPD = -0.140;
0.147). No effects on triglycerides (pooled MDΔ = 0.045 mmol/L; 95%HPD =
-0.195; 0.269) and body mass index (BMI) (pooled MDΔ = 0.062 kg/m²;
95%HPD = -0.293; 0.469) were found. Hazelnut-enriched diet is associated
with a decrease of LDL and total cholesterol, while HDL cholesterol,
triglycerides and BMI remain substantially unchanged.
KEYWORDS:
BMI; Corylus avellana; body weight; cholesterol; hazelnut; lipid; obesity; triglyceride
