Healthy Aging Resources

Live Life to the Full in Optimal Health

  • Sep 25

    Combined Grape Seed Extract and Vitamin C Supplementation Improves Vascular Health

    Grape seed extract (GSE) is rich in flavonoids including epicatechin. Vitamin C is an antioxidant that can help to prevent the oxidation and disappearance of phenol compounds. Recent clinical study demonstrated that the combination of GSE and vitamin C supplement can improve vascular health in people with clinically diagnosed CVD.

    Scientists at Boston University School of Medicine and USANA Health Sciences recently conducted a double-blind, randomised, placebo-controlled crossover study to examine the effects of GSE in combination with ascorbic acid on the effect of vascular indices including endothelium-dependent vasodilation.

    A total of 42 patients with coronary Artery Disease were treated with an acute dose of GSE (450 mg/day) plus ascorbic acid (1500 mg/day). After a 2-week washout period, patients received either an active (same total dose) or placebo treatment daily for 4 weeks (2 tablets in the morning and 2 tablets in the evening). Blood samples were collected and vascular testing were performed 2 and 4 hours post treatment (Acute) respectively. Tests were repeated after 4 weeks (Chronic) with the last dose taken the morning of the final day of a particular treatment (Acute-on-Chronic).

    The study found that treatment (Acute, Chronic, and Acute-on-Chronic) with the combination of GSE and vitamin C significantly increased serum vitamin C and plasma epicatechin level; Decreased SIN-1 induced 8-isoprostane formation indicating an increase in Plasma Antioxidant Reserve; and improved endothelial function in the peripheral microvasculature (capillaries and arterials).

    This finding is significant because oxidative stress is associated with a variety of chronic degenerative diseases including CVD. Thus, treatment with GSE plus vitamin C significantly increases the capacity to guard against the detrimental consequences of oxidative stress in the plasma. The role of endothelial dysfunction (decreased blood flow) in CVD is well established, therefore the finding that GSE plus vitamin C improves endothelial function (increased blood flow) suggests that GSE plus vitamin C supplementation work in a complimentary fashion to improve indices of vascular health by providing both antioxidant protection and improved microvascular endothelial function in patients with clinically diagnosed CVD.

    Source: Shenouda SM al; Grape Seed Extract Plus Vitamin C Improves Indices of Vascular Health 2009; USANA Clinical Research Poster;; Accessed 6 Sept 2010.

    Disclaimer: The information provided in the article is strictly educational. It may not be used to promote USANA products, nor is it intended as medical advice. For diagnosis and treatment of medical conditions, please consult your health care professional. This information may be copied and freely distributed only if all text remains intact and unchanged.

  • Jul 14

    Advanced Doses of Vitamin D Are Required To Achieve Optimal Vitamin D Status

    It is currently estimated that more than 1 billion people worldwide have vitamin D deficiency. Relatively small amounts of vitamin D are obtained through the diet and many lifestyle factors reduce endogenous vitamin D synthesis, therefore supplementation offers an important avenue for achieving and maintaining optimal vitamin D status.

    Scientists at USANA Health Sciences and Linus Pauling Institute recently conducted a clinical study to evaluate the effectiveness of moderately high daily doses of vitamin D3 on increasing circulating levels of vitamin D during winter, spring, and summer seasons.

    19 healthy volunteers, most using USANA’s HealthPakTM daily dietary supplement packs, BiOmegaTM and/or Active CalciumTM supplements, were randomly divided into the treatment or control (placebo) groups. The treatment group was given a daily supplement providing 4000 IU of vitamin D3 for three months from December 2008 to March 2009. The control group received a matching placebo tablet. Both the Vitamin D3 and matching placebo tablets were manufactured at USANA Health Sciences, Inc. (Salt Lake City, USA). Blood samples were drawn at baseline and after 4, 8, and 12 weeks of supplementation, to analyze circulating vitamin D levels (25-hydroxy vitamin D3).

    The study found that:

    * Treatment with 4000 IU/day significantly increased circulating vitamin D levels during the winter and maintained them in the optimal range above 50 mg/mL.
    * Circulating vitamin D levels reached maximal levels after 4 weeks of supplementation and plateaued thereafter.
    * Upon cessation of supplementation between weeks 12-16, vitamin D levels declined appreciably underscoring the need for continuous supplementation to maintain optimal levels throughout the winter and early spring.
    * Supplementation of 2000 IU/day through the late spring and summer maintained vitamin D levels in the optimal range.
    * At the conclusion of the study, vitamin D levels in all subjects that did NOT continue supplementation through the summer returned to the baseline values originally measured in December.

    This study shows that continuous intakes of vitamin D are needed to obtain optimal circulating levels of vitamin D above 50 mg/mL throughout the entire year.

    Source: Dixon B et al; 2009; USANA Clinical Research Poster; Accessed 21 Jun 2010.