Goji berry, or wolfberry (Lycium barbarum) has a long tradition as a health food in Asia as it is naturally abundant in carotenoids, Lycium barbarum polysaccharide (LBP) fraction, vitamin C precursor 2-O-(β-dglucopyranosyl) ascorbic acid, phenolic acids, and flavonoids.
Clinically, randomised controlled trials (RCTs) have found goji berry consumption has a positive influence on classical CVD risk factors, such as blood lipid–lipoprotein profiles and blood pressure.
However the majority of goji berry-based RCTs in the past have administered either goji berry fruit juice or LBP extract with few investigating the effects of whole goji berry consumption or potential influences from background diet. Moreover, no previous studies have explored a more comprehensive spectrum of vascular health-related biomarkers.
The present RCT therefore aimed to investigate the impact of a healthy dietary pattern recommended by the Singapore Health Promotion Board, the “My Healthy Plate” (MHP) diet, either with or without 15 g/d of cooked whole goji berry, on a broad spectrum of vascular health-related biomarkers.
The team conducted a 16-week, parallel design, randomised controlled trial involving 40 healthy middle aged participants (56 ± 1 years, 29 female) from Singapore. All participants received dietary counselling to follow healthy dietary pattern recommendations with the goji berry group given additional instructions to cook and consume 15 g/d whole, dried goji berry with their main meals.
Biomarkers of vascular function (flow-mediated dilation, plasma total nitrate/nitrite, endothelin-1, and intercellular adhesion molecule-1), vascular structure (carotid intima-media thickness) and vascular regeneration (endothelial progenitor cell count, plasma angiopoietin 1 and angiopoietin 2), were assessed at baseline and post-intervention. Serum lipid−lipoproteins and blood pressure were evaluated every four weeks.
Resulting data suggests all participants showed an improved compliance toward the healthy dietary pattern. This was coupled with marked rises in total nitrate concentrations (mean change goji berry: 3.92 ± 1.73 nmol/mL; control: 5.01±2.55 nmol/L) and reductions in endothelin-1 concentrations (goji berry: -0.19 ± 0.06 pg/mL; control: - 0.15 ± 0.08 pg/mL).
Compared with the control, which depicted no changes from baseline, the goji berry group had a significantly higher HDL cholesterol (0.08 ± 0.04 mmol/L), as well as lower Framingham predicted long-term CVD risk (-0.8 ± 0.5%) and vascular age (-1.9 ± 1.0 y) post-intervention. No differences were observed in the other vascular health-related outcomes.
Some limitations of this study include the small range of demographics in the sample group and the potential biases created by the difficulty in double blinding.
The authors conclude: "adherence to the MHP healthy dietary pattern contributes to improvements in vascular tone. With the addition of 15 g of whole, dried wolfberry daily, more prominent improvements were observed, specifically in terms of HDL cholesterol, as well as the overall long-term CVD risk, amongst middle-aged and older adults. These findings support the use of whole wolfberry as a dietary strategy to augment the cardiovascular protective benefits of a healthy dietary pattern...
"...As the first clinical trial to explore the impact of goji berry consumption on a broad spectrum of both classical CVD risk factors and biomarkers of vascular health, the present study may serve as preliminary data for the calculation of effect sizes in future research."
Source: The American Journal of Clinical Nutrition
Toh. D.W.K., Xia. X., Sutanto. C.N., Low. J.H.M., Poh. K.K, Wang. J.W., Sik-Yin Foo. R., Eun Kim. J.,
"Enhancing the cardiovascular protective effects of a healthy dietary pattern with wolfberry (Lycium barbarum): A randomized controlled trial"