The Brazilian researchers looked at the effects of taking 20g a day of commercially available creatine for a period of one week on 40 healthy males with an average age of 27.7. They used laser speckle contrast imaging and video microscopy to evaluate skin capillary density and reactivity before and after supplementation.
‘Microvascular’ refers to the smallest vessels within the circulatory system, such as capillaries, arterioles and venules.
“The main findings of this study are as follows: i) oral supplementation with creatine monohydrate in healthy, moderately physically active young adults improves systemic endothelial-dependent microvascular reactivity; ii) the supplementation also increased skin capillary density and recruitment, which are dependent on microvascular endothelial function; and iii) blood pressure was also reduced after the supplementation,” the researchers wrote in the Nutrition Journal.
Plasma levels of homocysteine- a non-protein amino acid – were not significantly impacted, although creatinine was increased and uric acid decreased. They said the results of the homocysteine levels (which decreased on average from 10.5 micromoles/litre to 10.1µmol/L after the trial) contrasted with previous research, but reiterated that their study looked at health young males. They planned further research on the effects of creatine supplementation in patients with diabetes, hypertension and dyslipidemia, with and without hyperhomocysteinemia.
Ups and downs of creatine supplements
After one week, the body mass of the participants increased on average from 74.9kg to 75.4kg, while their body mass index changed from an average of 25.2kg/m2 to 25.5kg/m2. The researchers said this was most likely caused by fluid retention.
Mean blood pressure decreased from 92.1mmHg (millimetre of mercury) before creatine supplementation to 89.8mmHg. Heart rate beats per minute increased from 56.7 to 57.5.
Discussing the results, they said: “Although further studies are necessary regarding this issue, it is possible that creatine supplementatin somehow contributes to increased epoxyeicosatrienoic acid bioavailability and may represent an important adjuvant therapy to improve endothelial function that is depressed in several metabolic and cardiovascular diseases.”
Epoxyeicosatrienoic acids are signaling molecules which act as anti-inflammatory hormones relating to the cardiovascular system and kidney.
Author: Nutrition Journal
Published online ahead of print, doi:10.1186/1475-2891-13-115
“Effects of dietary creatine supplementation on systemic microvascular density and reactivity in healthy young adults”
Authors: R. de Moraes, D. Van Bavel, B. Serpa de Moraes and E. Tibiriçá