UCP1 and obesity due to melanocortin 4 receptor deficiency: This anti-obesity activity of fucoxanthin was also examined in a human study, where according to Mikami (2017), fucoxanthin reduced HbA1c levels in subjects with G/G alleles of the UCP1 gene compared to those with the A/A and A/G alleles (thrifty allele of UCP1-3826A/G) in a human study consisting of 60 normal weight and obese Japanese adults with a BMI over 22 [62].