What damages your DNA and how to protect it?
Why do the mutations aka DNA errors occur?
Most of the mutations in the DNA come from copying the DNA in order to pass it on to new cells. When an egg cell is fertilized and it starts to multiply to form a human being with trillions of cells it needs to copy its DNA to pass it on to all of the new cells. Furthermore, the cells in our body are dying and multiplying all the time. But as the copy of the DNA is formed, there often occur mistakes that are left unrepaired. Just like in gossip every time a person tells a story forward a little part of the story can change. Luckily our body`s immune system can detect when there are too much mistakes in the cell`s DNA and those cells are killed. However if the cell has mutations that give it the ability to fool the immune cells and multiply without control then a tumor can develop. This is why cancer is a modern day disease. The older we get, the more mutations our cells accumulate and there is a higher probability of getting cancer.
ENVIRONMENT and RADIATION
Mutations can also occur due to environmental factors. Radiation that penetrates the skin`s upper layers (UV, X-rays and gamma rays) can damage the DNA. Mutation form because of the high energy that breaks chemical bonds in the DNA and forms new ones so the DNA structure changes and DNA`s code is unreadable. UV radiation makes new bonds between two T bases in the same strand when usually the base T pairs with the base A from the other strand. This leaves a gap in the DNA double helix and the DNA code might not be read correctly resulting in new mutations. This is why skin cancer and sunburns are associated with exposure to UV light and sunscreen should be used when exposed to sunlight (2)
Furthermore, UV light can generate free radicals and reactive oxygen species which travel through the body and react with all kinds of chemical molecules including DNA and proteins 3. This phenomenon is called oxidative stress. Another source of free radicals and reactive oxygen species (ROS) is the mitochondrion. Mitochondria are the organelles in our cells that provide energy by using the nutrients we consume as fuel. In this process however a lot of free radicals are formed. Oxidative stress is believed to be an important factor in neurodegenerative diseases like Parkinson's disease, Alzheimer's disease, Huntington's disease, Depression, autism etc (4),(5). Because free radicals can react with DNA and cause mutations oxidative stress is also related to cancer (6).
- Air pollution
- UV light
- Metabolism (fast-food or bad nutrition)
- Ionizing and radiation
- Too much or less physical activity
Usually cells can hold the free radicals under control with specific proteins and antioxidants. Antioxidants are molecules that help to control the ROS like carotenoids and vitamins E, C and A.
It is thought that by lowering oxidative stress antioxidants can better vascular function. Preliminary studies show that natural antioxidants such as goji berries, thymus, rosemary, green tea and garlic might prevent vascular damage (7). Another antioxidant resveratrol has been shown to decrease the risk of cardiovascular diseases. Resveratrol is found in grape skin, peanuts and berries. This molecule has also been associated with the French paradox by which the French have a much lower risk of cardiovascular disease (8). Unfortunally adding these to your diet as a dietary supplement gives various results on oxidative stress levels (9). Instead the antioxidants should be acquired from foods that have naturally high levels of antioxidants like berries and fruits. This can also prevent overdosage of the supplements.
|Antioxidant vitamins||Foods containing high levels of antioxidant vitamins (10),(11)|
|Vitamin C||Fresh or frozen fruits and vegetables|
|Vitamin E||Vegetable oils, nuts, and seeds|
|Resveratrol||Grape skin, nuts and berries|
|Carotenoids||Fruit, vegetables and eggs|