Introduction to Antioxidants
Before we discuss the benefits of eating foods high in antioxidants, let’s consider a couple of basic things first: What are antioxidants? What are the benefits of antioxidants? Can you eat enough for optimal health? If so, what is the most scrumptious way for you to get these important vitamins? So, let’s get started with the basics—what are they?
What are Antioxidants?
Antioxidants are nutrients (not just vitamins) found in certain foods and supplements that can put a stop to oxidation in the cells in our bodies. Oxidation (oxidative stress or OS) causes free radical damage to our cells and our DNA.
Antioxidants help prevent and even reverse macular degeneration, help prevent and reverse coronary artery disease, help prevent various types of cancer, help prevent Alzheimer’s, Periodontal disease and much more.
How do they Work?
The widely accepted mechanism by which antioxidants protect cells from oxidative stress is by scavenging free radicals and stopping lipid peroxidation chain reactions, which can cause DNA damage. Lipid peroxidation is the process in which free radicals “steal” electrons from the fatty acids in cell membranes, resulting in cellular damage.
Antioxidants work in conjunction with other antioxidants. There is a connection between oxidative damages and the occurrence of some diseases. For example, the oxidation of small, dense LDL particles by free radicals results in inflammation, which leads to cardiovascular disease. If you increase the consumption of supplements or foods high in antioxidants, you can reduce the damage from free radicals to reduce coronary plaque formation.
More Details on Free Radicals
A free radical is a chemical species with an unpaired electron that tends to be chemically unstable; wanting to “give away” it’s electron causing molecular damage in the process unless stopped by a neutralizing antioxidant molecule.
A certain amount of oxidative function is necessary for health. For example, oxidation is used by our immune systems to kill microorganisms. Sometimes, however, the level of toxic reactive oxygen species (ROS) overcomes the antioxidant defenses (tissue levels of antioxidants) of the biological host, resulting in an excess of free radicals. This physiologic state is called “having oxidative stress.” These free radicals cause local injury by reacting with lipids, proteins, and nucleic acids. The interaction of free radicals with a cell’s lipids leads to membrane damage and the generation of lipid peroxide byproducts which can cause DNA damage, and eventually cell mutations.
Cells contain antioxidants to help protect against free radical reactions.
The major water-soluble antioxidants are glutathione and vitamin C. Vitamin E and the carotenoids are the main fat-soluble antioxidants. Vitamin E is the main lipid-soluble antioxidant in cellular membranes that breaks the chain of lipid peroxidation. Therefore, theoretically, it might well be the most important antioxidant in preventing oxidation of these fatty acids. A reaction with vitamin C recycles vitamin E; emphasizing the importance of having a collection of antioxidants “on board,” rather than just being replete with, say, vitamin C.
Decreasing OS likely decreases inflammation, cortisol levels and therefore the incidence of leaky gut and thereby decreases all of the consequences of these issues.
Seek Out Specific Antioxidant Vitamins: Nutritional antioxidants
- Vitamin A (synthesized from beta-carotenes) – carrots, squash, broccoli, sweet potatoes, tomatoes, kale, peaches, apricots
- Vitamin C (ascorbic acid) – citrus fruits, green peppers, leafy vegetables, broccoli, strawberries, blueberries, cabbage, tomatoes
- Vitamin E – whole grains, wheat germ, nuts, seeds, green leafy vegetables, vegetable oil
Antioxidant vitamin cofactors and minerals
- Coenzyme Q10
- Zinc – protects red blood cells from oxidation
- Manganese – has antioxidant properties as part of the SOD enzyme
- and hundreds more!
Flavonoid polyphenolics (bioflavonoids)
- Green tea — one of the best antioxidant sources; green tea polyphenols are one of the most potent antioxidants
- Bioflavonoids sources include pomegranates, blueberries, blackberries, other types of tea and some coffee types
The benefits of antioxidants
Antioxidant nutrients are often thought to enhance immune function. Vitamin C, in particular, is generally perceived as useful in the prevention and treatment of the common cold. Some evidence does support a role of vitamin C, vitamin E, and carotenoids in enhancing immunity.
More and more evidence demonstrates that nutritional factors such as oxidative stress can influence risk for the development of cancer, prognosis following the diagnosis of cancer, and quality of life during cancer treatment. Epidemiologic evidence indicates that diets rich in fruits and vegetables are associated with a lower risk of a number of common cancers, particularly those of the oral cavity, lung, and cervix. Recent studies are showing the efficacy of IV vitamin C in certain cancers, as well.
Of all the chronic diseases in which excess oxidative stress has been implicated, coronary artery disease has the strongest supporting evidence for the positive role of antioxidants. Oxidation of small, dense, LDL particles are thought to be a key step in the development of atherosclerosis. Antioxidants are therefore probably useful in preventing, delaying and even reversing soft plaque in coronary arteries.
The eye is at particular risk of oxidative damage due to exposure to ultraviolet rays and large amounts of oxidizable fatty acids in the retina. In developed, western nations, age-related macular degeneration is the leading cause of blindness in the elderly. Cataracts are also a widespread problem in our older population.
The carotenoid antioxidants called zeaxanthin and lutein absorb blue light and protect against short wavelength damage to the retina.
Cataracts: Both epidemiologic and animal studies indicate that a large intake of a wide variety of antioxidant vitamins reduces the risk of cataracts.
Macular Degeneration: Epidemiologic studies show that there is a decreased incidence of age-related macular degeneration in smokers—all of whom, by definition, have high levels of oxidative stress. Studies also reveal that nonsmokers with higher intakes of fruits and vegetables, particularly those high in of lutein and zeaxanthin, have lower rates of AMD.
Inflammation and oxidative stress go hand in hand. Asthma is a condition of chronic inflammation of the lungs. The generation of free radicals by inflammatory cells produces many of the pathological changes associated with asthma. Antioxidants may, therefore, play a role in the prevention and treatment of asthma.
There is a good deal of literature documenting that periodontal disease is both prevented and improved with antioxidants. Green tea notably helps the cause. Diabetes control is likely better with antioxidants on board. Studies are revealing that pain management is better with certain antioxidants on board. Weight loss appears to be facilitated by antioxidants. Brain aging is decreased, with huge implications for degenerative brain issues such as Alzheimer’s disease. The list just goes on and on and includes a marked decrease in all-cause mortality with both increased carotenoids (alone) and increased antioxidant levels.
Foods with the Antioxidants you want
Food Sources for Various Antioxidants
Key sources of vitamin C include citrus fruits, strawberries, kiwifruit, papaya, and vegetables such as broccoli, red peppers, and (my favorite) brussels sprouts.
The best sources of vitamin E are wheat germ, almond and hazelnut oils, eggs and whole grain cereals.
Primary sources of beta-carotene include sweet potatoes, carrots, pumpkin, spinach, cantaloupe, pink grapefruit, apricots, broccoli, and dark green leafy vegetables.
Lycopene sources include tomatoes, tomato products such as sauces, green peppers, carrots, and apricots.
Zeaxanthin sources include spinach, corn, and fruits.
Lutein sources include corn, potatoes, green plants, carrots, spinach, and tomatoes.
Selenium sources include organ meats and seafood, eggs, grains, sunflower seeds, red meat, chicken and turkey.
Best antioxidant foods
Top 20 best and tastiest antioxidant foods:
Small red beans
Kidney beans and/or beverage white tea
Blueberries and/or “real” green tea (not teabag)
Blackberries and/or “real” black tea
Red Delicious and/or Granny Smith apples
Can you eat enough High-antioxidant Food for Optimal Health?
The National Institute of Health recommends 9-12 servings of colorful fruits and vegetables daily as part of a healthy diet to prevent cancer.
How close do you come to eating that much? What about juicing that much? It’s quite hard to do. But that’s not the whole story.
A well-known researcher noted in February of 2016 some alarming facts about the condition of our U.S. soil.
“Our planet has lost between 75-85% of its arable topsoil. This loss is due to erosion, improper use of inorganic nitrogen fertilizers, and other farming practices that leave the soil depleted. Topsoil loss and the related health and environmental issues must be considered a National Security concern. There is a consensus in the scientific community that this issue is the chief threat to future human survival.”
He continues to elaborate that soil erosion and topsoil loss over the last ten thousand years has been a direct result of the depletion of soil fiber, soil nutrients, and microorganisms. He cites references, predicting that all topsoil will be gone in less than 60 years; meaning that outdoor-grown nutritious vegetables and fruits are disappearing “mighty” fast.
If we look at the many hindrances to consuming enough full-value colorful fruits and vegetables, I believe it’s hard for anyone to “get what they need” from food sources, alone. The preponderance of studies which look at the value of pharmaceutical grade nutritional supplements are quite favorable. For that reason, I scan all patients with a Raman spec scanner to non-invasively measure oxidative stress, and then usually end up prescribing a high-antioxidant supplement for most. Please discuss this with your doctor. And of course, do eat your fruits and veggies!
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