Herbal Health Connections

Christen WG, Glynn RJ, Chew EY, Albert CM, Manson JE.

Division of Preventive Medicine, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, 900 Commonwealth Avenue E, Boston, MA 02215-1204, USA. wchristen@rics.bwh.harvard.edu

BACKGROUND: Observational epidemiologic studies indicate a direct association between homocysteine concentration in the blood and the risk of age-related macular degeneration (AMD), but randomized trial data to examine the effect of therapy to lower homocysteine levels in AMD are lacking. Our objective was to examine the incidence of AMD in a trial of combined folic acid, pyridoxine hydrochloride (vitamin B(6)), and cyanocobalamin (vitamin B(12)) therapy. METHODS: We conducted a randomized, double-blind, placebo-controlled trial including 5442 female health care professionals 40 years or older with preexisting cardiovascular disease or 3 or more cardiovascular disease risk factors. A total of 5205 of these women did not have a diagnosis of AMD at baseline and were included in this analysis. Participants were randomly assigned to receive a combination of folic acid (2.5 mg/d), pyridoxine hydrochloride (50 mg/d), and cyanocobalamin (1 mg/d) or placebo. Our main outcome measures included total AMD, defined as a self-report documented by medical record evidence of an initial diagnosis after randomization, and visually significant AMD, defined as confirmed incident AMD with visual acuity of 20/30 or worse attributable to this condition. RESULTS: After an average of 7.3 years of treatment and follow-up, there were 55 cases of AMD in the combination treatment group and 82 in the placebo group (relative risk, 0.66; 95% confidence interval, 0.47-0.93 [P = .02]). For visually significant AMD, there were 26 cases in the combination treatment group and 44 in the placebo group (relative risk, 0.59; 95% confidence interval, 0.36-0.95 [P = .03]). CONCLUSIONS: These randomized trial data from a large cohort of women at high risk of cardiovascular disease indicate that daily supplementation with folic acid, pyridoxine, and cyanocobalamin may reduce the risk of AMD.

Arch Intern Med. 2009 Feb 23;169(4):335-41.

by Le Ma, Xiao-Ming Lin, et al.

We aimed to examine the effect of different doses of lutein supplementation on visual function in subjects with long-term computer display light exposure.

Thirty-seven healthy subjects with long-term computer display light exposure ranging in age from 22 to 30 years were randomly assigned to one of three groups: Group L6 (6 mg lutein/day, n 12); Group L12 (12 mg lutein/day, n 13); and Group Placebo (maltodextrin placebo, n 12).

Levels of serum lutein and visual performance indices such as visual acuity, contrast sensitivity and glare sensitivity were measured at weeks 0 and 12. [Contrast sensitivity is ability to distinguish an object from its background. Glare sensitivity is ability to see objects in the presence of bright light.]

After 12-week lutein supplementation, serum lutein concentrations of Groups L6 and L12 increased from 0-356 (SD 0-117) to 0-607 (SD 0-176) mol/l, and from 0-328 (SD 0-120) to 0-733 (SD 0-354) mol/l, respectively. No statistical changes from baseline were observed in uncorrected visual acuity and best-spectacle corrected visual acuity, whereas:

• There was a trend toward increase in visual acuity in Group L12.

• Contrast sensitivity in Groups L6 and L12 increased with supplementation, and statistical significance was reached at most visual angles of Group L12.

• No significant change was observed in glare sensitivity over time.

Visual function in healthy subjects who received the lutein supplement improved, especially in contrast sensitivity, suggesting that a higher intake of lutein may have beneficial effects on the visual performance.

British Journal of Nutrition, Feb 19, 2009.