Saturday, September 1, 2012

Free Radicals and Antioxidants

All states of matter such as solid, liquid and gas are made up of minute particles called atom which is made up of a nucleus and electrons in its inner and outer shells. In the nucleus are the neutrons which is a particle with no charge and protons which are positively charged. The electrons are the negative charged particles. An element is a substance made up of only one type of atom. Example is hydrogen. A molecule is a group of two or more atoms of one or more types of an element that stick together to form a bond.  For example, a molecule of water is composed of two hydrogen atoms and one oxygen atom that are connected by covalent bond. All chemical reactions involve the transfer of electrons and a substance is oxidized when the electrons from its atoms or molecules are transferred or removed.                                                                                                                                

Our body is composed of billions of cells which are its building block. A cell contains countless of atoms of one or more elements. Atoms or molecules that lose electrons become unstable and interacts with other atoms to gain electrons. They are called free radicals. They need to “steal” or share electrons from other atoms or molecules to become stable. Affected molecules losing electrons will become free radicals too and interact to still other atoms or molecules. As a result there is a chain of reaction in the cells by molecules which strive to gain electrons. The actions of the molecules with unpaired electrons inside the cell will eventually cause damage to the DNA or the cellular membrane. It would be better to remove or kill affected cell to prevent it from affecting healthy cells. In the main, the accumulation of abnormal cells caused by free radicals will wreak havoc to the health of a person.

Some free radicals are produced by the body in its metabolism process. The body needs them for its immune system to kill harmful viruses and bacteria. However, when free radicals become excessive they caused the cells to become abnormal so that it will affect the well being of an individual. Overtime, the damage done to the DNA by free radicals will cause the cell to die and will hasten the ageing process of a person.

Some of the activities or conditions that cause the buildup of free radicals in the body include smoking of cigarettes, exposure to sunlight, pollution, pesticide, ageing and even excessive exercise. Ageing is a natural process whereby a person has more free radicals in the cells of his body as he gets older. Heart disease, cancer, macular degeneration, arthritis and diabetes are some of the many illnesses that are related to oxidative damage to the cells caused by free radicals.

Antioxidants are chemical substance that can contain free radical molecules before they can do vital damage to a cell. Antioxidants are free radicals scavengers. They can prevent and repair damages to a cell that are caused by free radicals. What makes antioxidants important is their ability to neutralize free radicals by donating electrons from its molecules to free radical molecules without their molecules becoming reactive.                                                      

There are enzymes of the body that are antioxidants, and there are substances or nutrients in our foods that are antioxidants too. Foods such as fruits and vegetables have antioxidant properties that can prevent or slow the oxidative damage to the cells of our body. Antioxidant properties of fruits are manifested by the bright color of its skin or flesh like orange, yellow, red or blue. For example, there is the yellow pigment of lutein in cantaloupe, squash and mangoes, and there is the red pigment of lycopene in tomatoes and watermelon.  

Known antioxidants are Vitamins A, C, E, carotenoid and selenium. Other antioxidants are flavanoids/polyphenols, lycopene, lutein and lignan. It is better to get antioxidants from foods rather than in supplements because the body can easily absorb them. Too much of vitamins like A and C if taken in excess will do more harm than good to the body.                                                                                                                                                                                                                                                                                                                              

The types of anti oxidants are the water soluble and fat soluble. Water soluble antioxidants are not stored in the body like Vitamin C.  The fat soluble needs to be taken with small amount of fat in order to be absorbed by the body. Examples are Vitamins A and E which are stored in the liver.

Following is list of foods rich in vitamins, minerals and nutrients that are antioxidants. The list includes but is not limited to the following foods:

Vitamin A:  liver, sweet potato, mango, carrot, spinach, cantaloupe, squash, milk and egg yolk

Vitamin C: red and green chili pepper, guava, bell pepper, dark green leafy vegetables, broccoli, kiwi fruit, papaya, oranges and strawberry.

Vitamin E: sunflower seeds, paprika and red chili powder, almond, peanut, pine nut, taro roots, spinach and pickled green olives.

Beta carotene: paprika, sweet potato, carrots, kale spinach

Selenium: fish and shellfish, red meat, grains, egg, chicken and garlic

Flavanoid/polyphenol: blueberry, cranberry, banana, oranges, apple, onion, eggplant, tomato, beer, red wine, nuts and beans, dark chocolate, red grapes, and tea.

Lycopene: tomato, guava, watermelon, grapefruit, basil, persimmon, asparagus, liver, chili powder and red cabbage

Lutein: kale, spinach, parsley, okra, red pepper, celery, broccoli, leeks, pumpkin, corn

Lignan: flax seeds, sesame seeds, curly kale, broccoli, apricots, cabbage, Brussels sprouts, strawberry, tofu

Related post: