Free radicals are unstable atoms that are naturally formed during metabolism or by exposure to environmental toxins. In excess, free radicals can damage cells, cause diseases, and accelerate aging.
While the body produces free radicals every day, its defense system is capable of eliminating the excess. However, when there is a disturbance in maintaining this balance, excess free radicals stay in the body and cause oxidative stress.
Multiple studies have shown that oxidative stress can lead to a range of diseases, including:
- Cardiovascular disease
- Certain cancers
- Macular degeneration
- Alzheimer's disease
- Parkinson's disease
- Gastric and duodenal ulcers
Other studies have linked the formation of free radicals to the acceleration of aging, such as wrinkles, metabolic disorders (such as diabetes mellitus), and damage to blood vessel lining.
What causes free radical formation?
Free radicals are produced naturally in the body every day. However, certain factors can increase their production:
What are antioxidants?
Antioxidants fight the damage caused by free radicals and minimize the effects of oxidative stress on your body. These defenders can be obtained from food and play a role in repairing DNA and maintaining the health of cells.
Some common antioxidants and their food sources include:
- Vitamin C
- Brussels sprouts
- Leafy greens (turnip, mustard, beets, collards)
- Bell peppers
- Vitamin E
- Swiss chard
- Leafy greens
- Red peppers
- Spinach (boiled)
- Sunflower seeds
- Carotenoids, such as beta-carotene and lycopene
- Bell peppers
- Collard greens
- Pink grapefruit
- Winter squash
- Sweet potato
- Brazil nuts
- Brown rice
- Whole grains
- Leafy greens
- Sesame seeds
- Pumpkin seeds
- Fortified cereals
- Red wine
- Red and white wine
- Coumaric acid
Health Solutions From Our Sponsors
Lobo V, Patil A, Phatak A, Chandra N. Free radicals, antioxidants and functional foods: Impact on human health. Pharmacogn Rev. 2010;4(8):118-126. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3249911/
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Common Medical Abbreviations & Terms
Doctors, pharmacists, and other health-care professionals use abbreviations, acronyms, and other terminology for instructions and information in regard to a patient's health condition, prescription drugs they are to take, or medical procedures that have been ordered. There is no approved this list of common medical abbreviations, acronyms, and terminology used by doctors and other health- care professionals. You can use this list of medical abbreviations and acronyms written by our doctors the next time you can't understand what is on your prescription package, blood test results, or medical procedure orders. Examples include:
- ANED: Alive no evidence of disease. The patient arrived in the ER alive with no evidence of disease.
- ARF: Acute renal (kidney) failure
- cap: Capsule.
- CPAP: Continuous positive airway pressure. A treatment for sleep apnea.
- DJD: Degenerative joint disease. Another term for osteoarthritis.
- DM: Diabetes mellitus. Type 1 and type 2 diabetes
- HA: Headache
- IBD: Inflammatory bowel disease. A name for two disorders of the gastrointestinal (BI) tract, Crohn's disease and ulcerative colitis
- JT: Joint
- N/V: Nausea or vomiting.
- p.o.: By mouth. From the Latin terminology per os.
- q.i.d.: Four times daily. As in taking a medicine four times daily.
- RA: Rheumatoid arthritis
- SOB: Shortness of breath.
- T: Temperature. Temperature is recorded as part of the physical examination. It is one of the "vital signs."
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What Happens in Oxidation?Free radicals are oxygen-containing molecules with an uneven number of negative charged subatomic particles (electrons). The uneven number of electrons makes these highly reactive. These free radicals react with oxygen in the body. This process is called oxidation.