Table 1.
Summary of human studies investigating the interaction between diet and SNPs in circadian clock genes.
| Authors (Ref) |
Sample Size (N) |
Study Design | Target Gene (Genetic Variants) |
Main Findings |
|---|---|---|---|---|
| Garaulet et al., 2009 [71] |
N = 1100 (540 men, 560 women) |
Cross-sectional study |
CLOCK rs4580704 C > G rs3749474 C > T rs1801260 (3111T→C) rs1464490 C > T rs4864548 G > A |
Association with obesity and MetS The minor allele G of rs4580704 showed lower risk of hypertension and diabetes. Protective effect the minor allele G of rs4580704 on insulin sensitivity when MUFA intake was >13.2% of energy. Different effects across CLOCK 3111T→C genotypes for saturated fatty acid intake (% of energy) (p = 0.017). |
| Garaulet et al., 2010 [89] |
N = 454 Overweight/obese, aged 20 to 65 | Dietary program based on the Mediterranean diet (28 weeks) |
CLOCK rs1801260 (3111T→C) rs3749474 C > T rs4580704 C > G rs1464490 C > T rs4864548 G > A |
Relationship between CLOCK SNPs and obesity. CLOCK rs1801260 may predict the outcome of body weight reduction strategies based on low-energy diets. |
| Garaulet et al., 2010a [81] |
N = 454 overweight/obese, aged 20 to 65 (380 women, 74 men) |
Weight loss intervention based on the Mediterranean diet |
PER2 rs230467 C > G rs4663302 C > T rs4663307 G > A |
Association with abdominal obesity (p < 0.05) Minor allele carriers G of rs2304672 displayed several obesogenic behaviors. The frequency of the carriers of rs4663307 minor allele who withdrew was greater than in those who successfully completed treatment. |
| Garaulet et al., 2012 [90] |
N = 1106 (715 lean and 391 overweight or obese, aged 20 to 65) |
Behavioral treatment for obesity based on a Mediterranean diet (30 weeks) |
SIRT1-CLOCK rs1467568 G > A 3111T > C |
A higher resistance to weight loss and a lower weekly weight loss rate in carriers of minor alleles at SIRT1 and CLOCK loci as compared with homozygotes for both major alleles. |
| Rahati et al., 2022 [75] |
N = 403 overweight and/or obese, aged 20 to 50 | Cross-sectional study |
CLOCK rs1801260 (3111T→C) |
Significant difference between genotypes for physical activity (p = 0.001), waist circumference (p < 0.05), BMI (<0.01), weight (p = 0.001), GLP-1 (p = 0.02), ghrelin (p = 0.04), appetite (p < 0.001), chronotype (p < 0.001), sleep (p < 0.001), food timing (p < 0.001), energy (p < 0.05), carbohydrate (p < 0.05), and fat intake (p < 0.001). |
| Lopez-Guimera et al., 2014 [91] |
N = 1272 overweight/obese aged 20 to 65 | Prospective longitudinal study |
CLOCK rs1801260 (3111T→C) |
SNP interacts with emotional eating behaviors for weight loss. |
| Garaulet et al., 2014a [82] |
N = 2414 (1404 Spanish Mediterranean 810 North American populations) |
Cross-sectional study |
REV-ERB-ALPHA1- rs2314339 G > A |
A lower probability of abdominal obesity in minor allele A carriers (OR = 1.5). No significantly association with energy intake but the physical activity was different by genotype. Interaction between the REV-ERB-ALPHA1 variant and MUFA intake for obesity in the Mediterranean population (p = 0.014). |
| Dashti et al., 2014 [87] |
N = 1548 (728 Mediterranean and 820 European origin North American populations) |
Cross-sectional study |
CRY rs2287161 G > C |
Significant interactions between the CRY1 variant and dietary carbohydrates for insulin resistance in both populations (p < 0.05). |
| Garaulet et al., 2011 [92] |
N = 1495 overweight/obese, aged 20 to 65 years | Cross-sectional study (weight loss program 12–14 weeks) |
CLOCK rs1801260 (3111T→C) |
Carriers of the minor C allele were more resistant to weight loss, showed shorter sleep duration, higher plasma ghrelin concentrations, delayed breakfast time, evening preference, and less compliance with a Mediterranean diet pattern than TT individuals. |
MeS: metabolic syndrome, OR: odd ratio, MUFA: monounsaturated fatty acids; BMI: body mass index.