Reactive Oxygen Molecules

Why adding fruits and vegetables to your diet is good for you.

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Definition: Reactive oxygen molecules, also known as reactive oxygen species or, ROS, are metabolic products formed from two types of cells that are involved in production and metabolism – the endoplasmic reticulum and the mitochondria. Reactive oxygen molecules have numerous biological effects. They can destroy bacteria and destroy human cells. Their function is to serve as messengers between cells and in the process of homeostasis.

Reactive oxygen molecules are produced continuously in all animals that breathe air. Because the normal metabolic path depends on the consumption and chemical use of oxygen, the production of reactive oxygen molecules is unavoidable.

Reactive oxygen molecules are different than normal oxygen molecules. They have been changed by the process of "oxidation" and are very unstable. Because they are  unstable, they tend to react with anything that they come in contact with. When in contact with cells in the body, or the DNA within those cells, the reaction can be damaging and causing cell death or DNA mutation.

When exposed to environmental stress, such as heat or UV rays, the levels of ROS will increase dramatically and damage cell structures. This damage is known as oxidative stress. ROS are also created from exogenous sources such as pollutants, tobacco, smoke, drugs, or ionizing radiation.

The positive effects of ROS on cell metabolism can be seen in the platelet responses to wound repair.

Yet, an excessive amount of ROS has been indicated in the inflammatory reactions seen in patients with cardiovascular disease, cochlear damage that leads to hearing impairment and congenital deafness, stroke, cancer, Alzheimer’s disease, and heart attack.

While it is important to limit the amount of reactive oxygen molecules, they serve an important function in the cell, including the function of the thyroid and the cellular response to bacterial infection.

Because of the danger seen with reactive oxygen molecules, methods have been developed to counteract their effects.

Methods to Reduce Reactive Oxygen Molecules

Primary among these is the production and use of chemicals called antioxidants. Antioxidants inhibit the oxidation of other molecules reducing the levels of reactive oxygen molecules before they can cause damage. Widely used in dietary supplements, antioxidants are classified as either water-soluble or lipid-soluble.

Three most powerful antioxidants and some of the foods that contain them are:

  • Beta-carotene – found in colorful fruits and vegetables such as apricots, asparagus, beets, broccoli, cantaloupe, carrots, corn, pumpkin, squash, and watermelon.
     
  • Vitamin C – found in berries, broccoli, Brussels sprouts, cauliflower, honeydew, kale, mango, strawberries, tomatoes, and papaya.
     
  • Vitamin E – found in avocado, chard, mustard or turnip greens, red peppers, sunflower seeds, and nuts.

Other healthy antioxidants include:

  • Zinc – found in dairy products, red meat, poultry, beans, nuts, seafood, and oysters.
     
  • Selenium – found in Brazil nuts, tuna, beef, and grain products

Antioxidants slow down or prevent the oxidation of other molecules. By incorporating at least five servings of fruits and vegetables to the diet, the body may be able to lessen the chances of heart disease, neurological disease, cancer and lowered immune system.

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