Blood pressure-lowering effect of astaxanthin may help fight type 2 diabetes: Iran RCT

06-Mar-2018 - Last updated on 08-Mar-2018 at 07:39 GMT

After astaxanthin supplementation, the study subjects' systolic blood pressure was lower than before the study. ©Getty Images

Astaxanthin supplementation may benefit type 2 diabetics by lowering their blood pressure and enhancing their glucose metabolism, say researchers in Iran.

One such product is astaxanthin, a natural keto-carotenoid found in several microorganisms and types of seafood.

Previous studies have found astaxanthin's antioxidant activity and effects on lipid metabolism to be a few times higher than those of vitamin C and α-tocopherol.

It also has a positive impact on cholesterol, and the immune response induced by antioxidant defence mechanisms in healthy subjects, or heart disease patients with enhanced antioxidant capacity.

Furthermore, clinical trials have pegged astaxanthin as a scavenger of free radicals and protective agents, particularly in the case of cardiovascular diseases.

However, the effects of dietary intake of astaxanthin on blood sugar and lipid profile have not yet been evaluated, especially in high-risk type 2 diabetes patients with enhanced inflammation and oxidative stress.

A natural remedy?

Based on this, researchers at the Ahvaz Jundishapur University of Medical Sciences and Shahid Chamran University in Iran conducted an RCT over eight weeks to explore the possible impact of astaxanthin supplementation on the insulin sensitivity, lipid peroxidation, glycaemic control, anthropometric indices and adiponectin concentration of 44 subjects with type 2 diabetes.

They divided the participants, aged 30 to 60 years, into two groups: the control group was given a placebo, while the treatment group was given 8mg of astaxanthin supplementation one a day for eight weeks.

After the eight-week trial, they observed that the participants in the treatment group exhibited increased serum adiponectin concentration and lowered visceral body fat mass.

Their serum triglyceride levels and very low-density lipoprotein (V-LDL) cholesterol concentrations had also been reduced, and their systolic blood pressure was lower than before the study.

The researchers added that astaxanthin supplementation had "significantly reduced the fructosamine concentration and marginally reduced the plasma glucose concentration" among those in the treatment group.

Valuable results

Regarding the study's limitations, they wrote that despite astaxanthin supplementation having improved insulin sensitivity, the results contradicted that of earlier animal studies, and they were unable to determine the underlying molecular mechanisms of astaxanthin's effects on human cells.

They were also unable to compare astaxanthin's hypoglycaemic and hypolipidemic effects with that of diabetic drugs in a dose-dependent manner.

However, they added that "these findings may provide new insights into the potential role of astaxanthin in modulating several conditions in participants with type 2 diabetes mellitus".

They then concluded: "We demonstrated that because participants with type 2 diabetes often have hypertriglycaemia and uncontrolled glucose metabolism, our findings of dual beneficial effects are clinically valuable.

"Our results offer a novel complementary treatment with potential impacts on diabetic complications without adverse effects."

Source: Asia Pacific Journal of Clinical Nutrition

https://doi.org/10.6133/apjcn.052017.11

"Astaxanthin improves glucose metabolism and reduces blood pressure in patients with type 2 diabetes mellitus"

Authors: Nafiseh Sokri Mashhadi, et al.