Can you repair DNA damage, or can you only prevent it?
Your body actively repairs DNA damage through multiple well-studied mechanisms, but that repair is not always perfect and becomes less effective when the cell is under excessive strain or grows older.
Your body actively repairs DNA damage every single day. Cells are constantly bombarded by harmful influences: from within, by by-products of metabolism, and from outside, by radiation and chemicals. This causes three types of damage: a break in one strand of the DNA, a break in both strands simultaneously, or damage to a single building block. The body has robust repair mechanisms that tackle this damage rather than merely preventing it.
The more severe the damage, the longer the repair takes. Breaks in both strands at once demand far more time from the cell than simpler forms of damage. Moreover, that repair is not always error-free: occasionally a small piece of DNA is permanently lost. Over time, such small losses can contribute to changes in the genetic material. When the repair mechanisms become structurally disrupted, damage accumulates. This is a well-known driver of cancer development.
There is also a flip side. Cancer cells with an especially strong repair capacity fix the DNA damage inflicted by chemotherapy more quickly than normal cells do. That makes the treatment less effective. Researchers are looking for ways to selectively inhibit this repair process in cancer cells.
The genetic material in your cells' energy factories, the mitochondria, is more vulnerable than the DNA in the nucleus. There are indications that this DNA can also be repaired, but exactly how that works is still far less well understood. Ideas about transferring healthy mitochondria as a therapy remain entirely hypothetical. Finally, DNA repair is not an isolated process: the cell's energy balance partly determines how well repair functions. Cellular fatigue, caused for example by ageing or disease, can therefore indirectly weaken the repair capacity.
Based on five to ten studies, including mechanistic and epidemiological research and several animal and cell culture studies. The core finding that cells actively repair DNA is robustly established; the details surrounding mitochondrial repair and therapeutic applications are still at an early stage of research.
Can DNA damage in your cells repair itself?
Your cells repair DNA damage constantly and on a large scale, but this capacity is not unlimited: complex or repeated damage can lead to errors that accumulate and drive diseases such as cancer.
Can you counteract DNA damage from ageing through your lifestyle?
Quitting smoking, exercising regularly and eating plenty of vegetables demonstrably reduce DNA damage; antioxidant supplements are unlikely to help with this.
Can diet protect your DNA from damage?
Diet has a real effect on DNA protection: a plant-based eating pattern and adequate folate and selenium demonstrably help, while heavily heat-processed meat and mouldy grains cause DNA damage. High antioxidant supplements are not a safe shortcut and can even be counterproductive.
Can smoking permanently damage your DNA?
Smoking damages your DNA in multiple ways simultaneously and leaves recognisable mutation patterns in at least 17 types of cancer. Quitting smoking demonstrably reduces the risk, as no association between smoking-related DNA damage and cancer has been found in former smokers.
What does a vitamin D deficiency do to your DNA?
A vitamin D deficiency is associated with greater DNA damage, especially in people with an additional risk factor. Make sure your vitamin D level is adequate, but if you are unsure about supplementation, consult your general practitioner.
How do telomeres protect your DNA?
Telomeres protect your chromosome ends through a system of proteins that simultaneously prevents false alarms and harmful fusions. If that system fails due to inherited defects, you can develop serious ageing-related diseases.