Nutraceutical: Beta-carotene

Indication: Memory

 

Source:

Arch Intern Med, Nov 12, 2007;167(20):2184-90.

Research:

Oxidative stress contributes to brain aging, which is why the researchers in this study felt antioxidants, especially over the long term, might confer cognitive benefits. They started by adding cognitive testing to the Physicians’ Health Study II (PHSII), a randomized trial of beta-carotene and other vitamin supplements for chronic disease prevention. PHSII is a continuation of the Physicians’ Health Study (PHS), which had randomized male participants to low-dose aspirin and beta-carotene. Participants include those continuing their original beta-carotene assignment from the PHS, begun in 1982, and newer recruits randomized as of 1998. The beta-carotene arm (50 mg, alternate days) was terminated; follow-up is ongoing for the remaining arms. Near the close of the beta-carotene arm, researchers interviewed nearly 6000 participants older than 65 years to assess general cognition, verbal memory and category fluency. The primary endpoint was a global score averaging all tests (using z scores); the secondary endpoint was a verbal memory score combining results of four tests. Researchers compared mean cognition among those assigned to beta-carotene vs. placebo. Then they separately ex­amined new recruits and continuing participants.

Results:

Among 1904 newly recruited subjects (mean treatment duration, 1 year), cognition was similar across treatment assignments. Among 4052 continuing participants from the PHS (mean treatment duration, 18 years), the mean global score was significantly higher in the beta-carotene group than in the placebo group. On verbal memory, men receiving long-term beta-carotene supplementation also performed significantly better than the placebo group. Researchers said although they did not see an impact of short-term beta-carotene supplementation on cognitive performance, they believe long-term supplementation may provide cognitive benefits.

Nutraceutical: Sytrinol (citrus bioflavonoid/palm tocotrienol combination)

Indication: Cholesterol-lowering

Source:

Alternative Therapies in Health & Medicine, November/December 2007;13(6):44-8.

Research:

Preliminary studies have suggested that both citrus flavonoids and palm tocotrienols reduce cholesterol levels in laboratory animals. To test this theory, researchers examined the effect of these nutrients in combination on blood levels of cholesterol and related cardiovascular disease risk factors. Two open-label studies and one double-blind study were initiated. Three groups (n=10, n=10, n=120) of hypercholesterolemic men and women (cholesterol levels >230 mg/dL) between the ages of 19 and 65 years were recruited. Subjects were randomized to consume either 270 mg citrus flavonoids plus 30 mg tocotrienols (Sytrinol) or placebo (P) daily for a period of 4 weeks (group 1 [G1] and group 2 [G2]) or 12 weeks (group 3 [G3]). Measurements of fasting levels of blood cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), and triglycerides were made at baseline and 4 weeks (all groups), as well as at 8 weeks and 12 weeks (G3).

Results:

Daily treatment with Sytrinol significantly improved cardiovascular parameters compared to placebo in all groups. Significant reductions were shown in total cholesterol (20%-30%), LDL (19%-27%), apolipoprotein B (21%) and triglycerides (24%-34%).

Nutraceutical: Vitamin B12

Indication: Cognitive decline

Source:

Am J Clin Nutr, November 2007;86(5):1384-91.

Research:

Elevated total homocysteine (tHcy) concentrations have been associated with cognitive impairment, but it is unclear whether low vitamin B12 or folate status is responsible for cognitive decline. So researchers decided to examine the associations of cognitive decline with vitamin B12 and folate status in a longitudinal cohort study performed from 1993 to 2003 in Oxford, U.K. Cognitive function was assessed with the Mini-Mental State Examination on at least three occasions during 10 years and related to serum concentrations of vitamin B12, holotranscobalamin (holoTC), tHcy, methylmalonic acid (MMA), and folate with the use of linear mixed models in 1648 participants who provided blood in 1995.

Results: Cognitive function declined abruptly at younger ages in some participants but remained intact in others until very old age. In multivariate regression analyses after adjustment for established risk factors, concentrations of holoTC (a marker of reduced vitamin B12 status), tHcy, and MMA predicted cognitive decline, but folate did not. A doubling in holoTC concentrations (from 50 to 100 pmol/L) was associated with a 30% slower rate of cognitive decline, whereas a doubling in tHcy (from 10 to 20 mumol/L) or MMA (from 0.25 to 0.50 mumol/L) was associated with a greater than 50% tendency toward more rapid cognitive decline. After adjustment for all vitamin markers simultaneously, the associations of cognitive decline with holoTC and MMA remained significant. This led researchers to conclude that low vitamin B12 status could initiate more rapid cognitive decline. Randomized trials, however, are required to determine the relevance of vitamin B12 supplementation for prevention of dementia.

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