Deoxyribonucleic acid, commonly known as DNA, is a molecule that carries the genetic instructions used in the growth, development, functioning and reproduction of all known living organisms.
DNA damage occurs when there is an alteration in the chemical structure of DNA through:
- a break in a strand of DNA
- a base missing from the backbone of DNA
- a chemically changed base
The vast majority of DNA damage affects the primary structure of the double helix in which the bases are chemically modified. These modifications can in turn disrupt the molecules’ regular helical structure by introducing non-native chemical bonds or bulky adducts that do not fit in the standard double helix.
DNA damages that are naturally occurring due to metabolism and its byproducts occur at a high rate in the body. Most of these damages to DNA from naturally occurring metabolism are repaired. However, there may remain some DNA damage despite the action of repair processes. These remaining DNA damages accumulate in the tissues.
There are a number of sources that contribute to DNA damage. DNA damage can be subdivided into two main types, either endogenous damage from naturally occurring metabolic processes and/or exogenous damage caused by external agents.
Endogenous damage caused by metabolic byproducts (naturally occurring):
- Reactive oxygen species (free radicals)
- Alkylation of bases (usually methylation), such as formation of 7-methylguanosine, 1-methyladenine, 6-O-Methylguanine
- Hydrolysis of bases, such as deamination, depurination, and depyrimidination.
- “Bulky adduct formation” (i.e., benzo[a]pyrene diol epoxide-dG adduct, aristolactam I-dA adduct)
- Mismatch of bases, due to errors in DNA replication, in which the wrong DNA base is stitched into place in a newly forming DNA strand, or a DNA base is skipped over or mistakenly inserted.
- Monoadduct damage cause by change in single nitrogenous base of DNA
- Diadduct damage
Exogenous damage caused by external agents such as:
- Air pollutants 5
- Heavy Metals
- Aflatoxin A1 (toxic chemicals produced by Aspergillus fungi growing on grains and peanuts) 12 13 14
- Bisphenol A (BPA) (used in making all kinds of plastics and resins, including water bottles and food containers) 15 16
- Pesticides and herbicides 17 18 19
- Heterocyclic aromatic amines (HAAs) (from cooked meats at high temperatures) 20
Whether by endogenous metabolism or exposure to exogenous agents, the DNA repair process is constantly active. The rate of DNA repair is dependent on many factors, such as:
- the cell type
- the age of the cell
- the extracellular environment
Enhancing and maintaining DNA repair processes is vital to the integrity of the cell and its functionality.
In order to protect DNA from endogenous and exogenous damage, an important strategy is to consume nutrients that can not only prevent or mitigate the damage to DNA but also enhance and strengthen the DNA repair process.
A number of nutrients have been identified and researched for their ability to prevent DNA damage and/or promote the repair of damaged DNA.
The Table below list those nutrients that prevent DNA damage and promote their repair:
Nutrients that Prevent DNA Damage and Promote Their Repair
Category Nutrient Reference
Category Nutrient Reference
Amino Acids Acetyl-L-Carnitine 1
Auxins Indole-3-Carbinol 3
Carotenoids Astaxanthin 4
Fatty Acids Fish oil (omega-3 fats) 7
Hormones Melatonin 8
Minerals Selenium 9
Polyphenols Genistein (from soy) 11
Epigallo-Catechin-Gallate (EGCG) 13
Oligomeric Proanthocyanidins (OPCs) 15
Ellagic Acid 19
Ferulic Acid 20
Porphyrins Chlorophyllin 21
Probiotics Lactobacillus rhamnosus 22
Quinones Coenzyme Q10 23
Vitamins Choline 24
Folic Acid 25
Inositol Hexaphosphate (IP6) 26
Vitamin B3 (Niacinamide form of Vitamin B3) 27
Vitamin C 28
Vitamin E (Tocotrienols) 29
Vitamin D3 30
Herbs Cat’s Claw 31
Rhodiola rosea 32
Korean Ginseng 33