Antioxidants Flashcards
What occurs when molecules lose electrons?
Oxidation
What sometimes happens when oxygen oxidizes a molecule?
The molecule becomes a free radical
What is an atom or molecule containing an unpaired electron?
Free radical
What is the common oxidizing agent that can become a free radical?
Oxygen
What occurs when molecules gain electrons ?
Reduction
Are free radicals always bad?
No
Which cells use free radicals as a chemical defense?
Immune cells
What are the 2 reasons why the overproduction of free radicals is problematic?
- It causes a chain reaction of free radical formation
2. It can damage cellular structures
Which cellular structure is the most damaged by free radicals?
The cell membrane
What is the free radical theory of aging?
The more free radicals you have the faster you are going to age
What 6 other diseases are thought to be causes, in part, by free radicals?
- Macular degeneration
- Cardiovascular disease
- Cancer
- Alzheimer’s disease
- Parkinson’s disease
- All inflammatory diseases (arthritis and lupus)
How does the body control the production of free radicals?
It uses defenses
What 2 things does the body use to keep free radicals under control?
Enzymes and Antioxidants
What are chemicals derived from food?
Antioxidants
Are the most antioxidant vitamins found in plants or animals?
Plants
Why is vitamin E found at high levels in certain plant foods?
Plants deal with a lot of UV light
Which tissues in the body have high levels of vitamin E?
Red blood cells and lung tissue
Why do red blood cells and lung tissue have high levels of vitamin e?
They are exposed to a lot of light
What are the main dietary sources of vitamin E?
Plant seed oils (canola, corn, soybean), olive oil, spinach, eggs yolks, nuts, avocado
What are the 2 roles of vitamin C in the body?
- Readily accepts and donates vitamin E
2. Aids in the reactivation of vitamin E
What are the main dietary sources of vitamin C?
Citrus fruits, strawberries, green peppers, cauliflower, broccoli, whale skin and other organ meats
What deficiency results from inadequate vitamin C intake?
Scurvy
What are the symptoms of scurvy?
Pinpoint hemorrhages under the skin, fatigue, bleeding gums, joint pain, wounds that would not heal
Which people were the first to get scurvy?
Sailors
How was scurvy cured?
Citrus fruits (lemons)
What are phytochemicals with health-promoting properties?
Carotenoids
Which carotenoid can be converted into vitamin A in the body?
Beta-carotene
What contains carotenoids?
Plants
What are some problem with getting vitamin A solely from this carotenoid?
Low rates of absorption and conversion
What are 3 other carotenoids that have health benefits?
Lycopene, Zeaxanthin, and Lutein
What are foods that carotenoids are found in?
Tomatoes, kale, spinach, peas, broccoli, roman lettuce, brussels sprouts, zucchini
How does selenium function as an antioxidant?
It spares vitamin E and helps maintain cell membrane integrity
What does selenium work in place of?
Vitamin E
What are the dietary sources of selenium?
Fish, meat (esp. organ meats), shellfish, eggs, Brazil nuts
What environmental factor affects the food levels of selenium?
The soil contents
What are 5 toxicity symptoms associated with selenium?
Hair loss, weakness, nausea, vomiting and cirrhosis
Which geographical location has low selenium in the soil?
North America
Is excess supplementation of selenium toxic?
Yes
