You must read and accept the disclaimer to use this site. Updated for monthly, 2011

You must read and accept the disclaimer to use this site.

Vitamin: B1, thiamin

Daily Value: 1.5 mg

Hazardous level: safe at more than 10xRDA

Average intake in US diet: 1.75 mg

Function: Thiamin pyrophosphate is a coenzyme required for the oxidative decarboxylation of alpha-keto acids and for the activity of transketolase in the pentose phosphate pathway. Facilitates use of carbohydrates for energy; helps maintain nerve function and muscle tone; aids growth and healthy appetite

DOSAGE RATIONALE: B1 is like vitamin C, safe and inexpensive. Therefore, there is no harm in including close to the RDA, and some people have "marginal" levels.

NOTES AND KEY REFERENCES:

Curz, A., et al "Longitudinal changes in the intake of vitamins and minerals of elderly Europeans", Eur J Clin Nutr 50: S77-85 (1996)

658 elderly men and 731 elderly women born 1913-18: "A significant decrease in the median intake of vitamin B1, B2, B6, C or iron was observed..."- low B1 intake in elderly

van der Wielen, R. P. , et al, "Nutritional status of elderly female nursing home residents: the effect of supplementation with a physiological dose of water-soluble vitamins", Eur J Clin Nutr 49: 665-74 (1995)

supplementation of 42 women over 60 in nursing homes. "50% of the daily dietary recommendation of water-soluble vitamins" "significantly improved the concentrations of thiamin and pyridoxal, increased body weight and decreased serum homocysteine"- dietary supplements improved thiamin in elderly

van der Wielen, R. P. , et al, "Dietary intakes of energy and water-soluble vitamins in different categories of aging", J Gerontol 51: B100-7 (1996)

"Dietary intakes of [thiamin, riboflavin, B6, and C] were below the minimum requirements in almost half of the nursing home residents"- dietary intakes below RDAs in half of nursing home residents

Alhadeff, L. et al, "Toxic effects of water-soluble vitamins", Nutr. Rev. 42: 33-40 (1984)

"it is now known that high doses of water-soluble vitamins may indeed have toxic effects"

Table II: vitamin disorder

nicotinic acid asthma, diabetes, liver, gout, cardiac, CNS

folate masks B12 deficiency, causes insomnia

pantothenate causes diarrhea

B1 causes irritability

B6 causes convulsions, antagonizes L-dopa in

Parkinsons, neural troubles

-thiamin is safe at high doses

Benton D; Haller J; Fordy J, "The vitamin status of young British adults", Int J Vitam Nutr Res 67(1):34-40 (1997)

"thiamin, riboflavin, pyridoxine, ascorbic acid, retinol, alpha-tocopherol, folic acid, cyanocobalanin, carotene and biotin status were assessed in a sample of 243 young British adults... The status of ascorbic acid, cyanocobalamin, alpha-tocopherol, folic acid and in males retinol, was adequate in the majority of cases. In the cases of riboflavin and pyridoxine the status of a substantial minority was either borderline or deficient. The thiamin and biotin status of a minority of both sexes, and retinol in the females, was marginal"

for 243 British students, the thiamin status of a minority of both sexes was marginal

WHITE PAPER REFERENCES FOR STAY WELL FORMULATIONS

Benton, D., Griffiths, R., and Haller, J., "Thiamine supplementation mood and cognitive functioning", Psychopharmacology 129: 66-71 (1997)

"There is a series of double-blind placebo controlled studies that report, in at least some of the population, that micronutrient supplementation is associated with better mood...Heseker et al found an improvement in mood using a 3-mg supplement"