Tags

Type your tag names separated by a space and hit enter

Micronutrients prevent cancer and delay aging.
Toxicol Lett. 1998 Dec 28; 102-103:5-18.TL

Abstract

Approximately 40 micronutrients are required in the human diet. Deficiency of vitamins B12, folic acid, B6, niacin, C, or E, or iron, or zinc, appears to mimic radiation in damaging DNA by causing single- and double-strand breaks, oxidative lesions, or both. The percentage of the US population that has a low intake (< 50% of the RDA) for each of these eight micronutrients ranges from 2% to > or = 20%; half of the population may be deficient in at least one of these micronutrients. Folate deficiency occurs in approximately 10% of the US population, and in a much higher percentage of the poor. Folate deficiency causes extensive incorporation of uracil into human DNA (4 million/cell), leading to chromosomal breaks. This mechanism is the likely cause of the increased cancer risk, and perhaps the cognitive defects associated with low folate intake. Some evidence, and mechanistic considerations, suggest that vitamin B12 and B6 deficiencies also cause high uracil and chromosome breaks. Micronutrient deficiency may explain, in good part, why the quarter of the population that eats the fewest fruits and vegetables (five portions a day is advised) has approximately double the cancer rate for most types of cancer when compared to the quarter with the highest intake. Eighty percent of American children and adolescents and 68% of adults do not eat five portions a day. Common micronutrient deficiencies are likely to damage DNA by the same mechanism as radiation and many chemicals, appear to be orders of magnitude more important, and should be compared for perspective. Remedying micronutrient deficiencies is likely to lead to a major improvement in health and an increase in longevity at low cost. Aging appears to be due, in good part, to the oxidants produced by mitochondria as by-products of normal metabolism. In old rats mitochondrial membrane potential, cardiolipin levels, respiratory control ratio, and overall cellular O2 consumption are lower than in young rats, and the level of oxidants (per unit O2) is higher. The level of mutagenic aldehydes from lipid peroxidation is also increased. Ambulatory activity declines markedly in old rats. Feeding old rats the normal mitochondrial metabolites acetyl carnitine and lipoic acid for a few weeks, restores mitochondrial function, lowers oxidants to the level of a young rat, and increases ambulatory activity. Thus, these two metabolites can be considered necessary for health in old age and are therefore conditional micronutrients. This restoration suggests a plausible mechanism: with age-increased oxidative damage to proteins and lipid membranes causes a deformation of structure of key enzymes, with a consequent lessening of affinity (Km) for the enzyme substrate; an increased level of the substrate restores the velocity of the reaction, and thus restores function.

Authors+Show Affiliations

University of California, Berkeley 94720-3202, USA. bnames@uclink4.berkeley.edu

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.
Review

Language

eng

PubMed ID

10022226

Citation

Ames, B N.. "Micronutrients Prevent Cancer and Delay Aging." Toxicology Letters, vol. 102-103, 1998, pp. 5-18.
Ames BN. Micronutrients prevent cancer and delay aging. Toxicol Lett. 1998;102-103:5-18.
Ames, B. N. (1998). Micronutrients prevent cancer and delay aging. Toxicology Letters, 102-103, 5-18.
Ames BN. Micronutrients Prevent Cancer and Delay Aging. Toxicol Lett. 1998 Dec 28;102-103:5-18. PubMed PMID: 10022226.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Micronutrients prevent cancer and delay aging. A1 - Ames,B N, PY - 1999/2/18/pubmed PY - 1999/2/18/medline PY - 1999/2/18/entrez SP - 5 EP - 18 JF - Toxicology letters JO - Toxicol Lett VL - 102-103 N2 - Approximately 40 micronutrients are required in the human diet. Deficiency of vitamins B12, folic acid, B6, niacin, C, or E, or iron, or zinc, appears to mimic radiation in damaging DNA by causing single- and double-strand breaks, oxidative lesions, or both. The percentage of the US population that has a low intake (< 50% of the RDA) for each of these eight micronutrients ranges from 2% to > or = 20%; half of the population may be deficient in at least one of these micronutrients. Folate deficiency occurs in approximately 10% of the US population, and in a much higher percentage of the poor. Folate deficiency causes extensive incorporation of uracil into human DNA (4 million/cell), leading to chromosomal breaks. This mechanism is the likely cause of the increased cancer risk, and perhaps the cognitive defects associated with low folate intake. Some evidence, and mechanistic considerations, suggest that vitamin B12 and B6 deficiencies also cause high uracil and chromosome breaks. Micronutrient deficiency may explain, in good part, why the quarter of the population that eats the fewest fruits and vegetables (five portions a day is advised) has approximately double the cancer rate for most types of cancer when compared to the quarter with the highest intake. Eighty percent of American children and adolescents and 68% of adults do not eat five portions a day. Common micronutrient deficiencies are likely to damage DNA by the same mechanism as radiation and many chemicals, appear to be orders of magnitude more important, and should be compared for perspective. Remedying micronutrient deficiencies is likely to lead to a major improvement in health and an increase in longevity at low cost. Aging appears to be due, in good part, to the oxidants produced by mitochondria as by-products of normal metabolism. In old rats mitochondrial membrane potential, cardiolipin levels, respiratory control ratio, and overall cellular O2 consumption are lower than in young rats, and the level of oxidants (per unit O2) is higher. The level of mutagenic aldehydes from lipid peroxidation is also increased. Ambulatory activity declines markedly in old rats. Feeding old rats the normal mitochondrial metabolites acetyl carnitine and lipoic acid for a few weeks, restores mitochondrial function, lowers oxidants to the level of a young rat, and increases ambulatory activity. Thus, these two metabolites can be considered necessary for health in old age and are therefore conditional micronutrients. This restoration suggests a plausible mechanism: with age-increased oxidative damage to proteins and lipid membranes causes a deformation of structure of key enzymes, with a consequent lessening of affinity (Km) for the enzyme substrate; an increased level of the substrate restores the velocity of the reaction, and thus restores function. SN - 0378-4274 UR - https://www.unboundmedicine.com/medline/citation/10022226/Micronutrients_prevent_cancer_and_delay_aging_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0378-4274(98)00269-0 DB - PRIME DP - Unbound Medicine ER -
Try the Free App:
Prime PubMed app for iOS iPhone iPad
Prime PubMed app for Android
Prime PubMed is provided
free to individuals by:
Unbound Medicine.