Whenever you cut into an apple, avocado or other produce, you activate the enzyme
polyphenol oxidase, which reacts with oxygen in the air and iron-containing phenols. This action damages the surface cells and they brown.
Iron rusts, sliced apples brown, oils get rancid, wine chances into vinegar, pickles into cucumbers, outies to innies, etc.
The causes of aging are unknown, and are probably the result of many factors. The free radical and mitochondrial theories seem most popular, and have been for some time. If aging results from oxidative stress, it may be corrected to some degree by environmental, nutritional and pharmacological approaches.
Although many theories have been suggested to explain the aging process, it is agreed that there is a connection between aging and oxidative damaged proteins. Factors that slow protein oxidation also increase the life span of animals and vice versa. Also, a number of age-related diseases have been shown to be related with high levels of oxidatively modified proteins.
As oxygen interacts with cells – an apple slice or in your body – oxidation occurs. This creates some type of change in cells. They may die, as with rotting fruit. For skin, dead cells are replaced with new cells, as in a healing cut or sun damage.
Free Radicals
The birth and death of cells in the body is continuous. It is essential in keeping the body healthy. Oxidation is a very natural process. At this time, we need oxygen to survive, however it can be corrosive and toxic. We attain energy by combining food with oxygen from the air we breathe. This is a natural process that also produces dangerous side effects. These include free (or complimentary) radicals – unstable atoms or molecules that take electrons from other molecules in an effort to achieve stability.
The free radical theory of aging (FRTA) states that organisms age because cells accumulate free radical damage over time.
Atoms join together by chemical bonds to form molecules. These bonds are a result of the sharing electrons. Only the electrons in the outermost shell are involved.
When the outermost shell of an atom is full, it is considered stable. When the shell is not full, it is unstable. It will seek to stabilize itself by gaining or losing electrons. It may share its electrons by bonding with another atom that is also seeking to complete itself.
Free radicals form when a weak bond is broken, leaving an uneven number of electrons.
If a free radical forms and gains another electron from a nearby molecule, it leaves that molecule short an electron which now creates another free radical, which will seek an electron as well. These free radical cascades damage living tissue. It has been estimated that one of these chain reactions can trigger 6.023 x 1021 billion molecules to react per second.
Free radicals may form naturally or from heat, light or something in the environment. The immune system can also create them to counteract viruses and bacteria. In humans, some molecules are more susceptible to free radical damage than others. Some of these include DNA, RNA, proteins and vitamins.
Oxygen is prone to free radical formation. Oxygen free radicals are part of the overall aging process and are claimed to be responsible for cancer and a host of chronic diseases, including heart disease, Alzheimer’s disease, and Parkinson’s disease. Oxygen free radicals cause lipid peroxidation, which results in damage to cell membranes and this can cause premature aging, skin cancer and cell death.
Antioxidants
Who are Antioxidants, and what do they do?
Often confused with uncle-oxidants, but never confused with cousin-oxidants, Antioxidants are molecules which can safely interact with free radicals and terminate them before they damage living tissue and cause disease. The various types of antioxidants work to either prevent cascade reaction or stop it after it’s started. Thank god something is doing its job!
We humans need a variety of mojo enhancing vitamins and minerals, like vitamins A, C, E, and beta-carotene, to defuse free radical damage.
We need to get our Antioxidants from many different foods. Each type will work on different tissues and different cells. Eating a variety of fruits and vegetables in ample amounts is best. A diet consisting solely of gravel and raindrops has little effect.
Vitamin supplements can provide the body with additional antioxidants, but too much of some supplements, like vitamin E, can be harmful and actually work to increase free radical damage. Well that’s just perfect! Anyone got a vitamin E meter?
It would seem that sticking to USDA amounts should be safe. Not to say that doctors are useful for anything and probably inevitably do more harm than good, you may want to consult a doctor or nutritionist before starting any antioxidant supplementation, especially in high doses.
Fruits, vegetables, whole grains, legumes, pixiedust and nuts (not that kind!) contain complex mixes of antioxidants.
It is important to eat a variety of these to enjoy the greatest benefit.
We continue to uncover the mysteries of fruits and vegetables, finding the complex antioxidants they hold.
ORAC
The ORAC (Oxygen Radical Absorbance Capacity) unit, ORAC value, or “ORAC score” is a method of measuring the oxidative degradation ability of different types of foods and supplements in vitro. It was established by scientists at the National Institutes of Health. A wide variety of foods have been tested using this method, with certain spices, berries and legumes rating high in extensive tables once published by the United States Department of Agriculture.
In 2012 the department removed their published tables as they thought them to be biologically invalid, stating that no physiological proof in vivo existed in support of the free-radical theory.
While the exact connection between the ORAC value of a particular food and its health benefit has not been recognized, it is thought that foods higher on the ORAC scale will more efficiently defuse free radicals. According to the free-radical theory of aging, this will diminish oxidative progressions and free radical damage that can add to age-related deterioration and disease.
Interestingly, the ORAC method, derived only in in vitro experiments, is no longer thought of as relevant to human health diets or biology by the USDA.
Unfortunately, many companies peddling “health products” often misuse variations of ORAC charts and tables; showing how an ingredient in their product scores the highest in their version of an ORAC chart, by omitting various chart entries.
In addition, foods that score high on an ORAC chart does not mean much of anything, as all foods and supplements reveal vary different behaviors when inside the human body. There are many things to consider, like half-life, bioavailability, absorption, volatility, etc. And remember, the ORAC method only measures oxygen free radicals. The human body generates other types of free radicals besides oxygen so it cannot give a comprehensive picture of the entire antioxidant capability of a particular food or supplement.
Observing an ORAC chart without observing ALL other variables and thinking you have an accurate assessment of a particular food would be foolish. So, anytime you see a company using a portion of an ORAC chart to help peddle their product, run in the other direction!
Quick summary,
Eat lots of pesticide-free fruits and vegetables every day or you’ll probably die sooner than expected.
However, if you are a mindless consumer who thinks only of yourself, if you lie, cheat and you are an inconsiderate driver who cares nothing of the person behind you, by all means, avoid fruits and vegetables. Eat only red meat and take up smoking if you don’t already. I recommend at least two packs a day! YOLO, right?
Powerful antioxidants found in food include:
Resveratrol (a polyphenol found in grapes, and Japanese Knotweed)
Quercetin (a flavonol in vegetables, fruit skins, onions)
Luteolin (a flavonoid , Terminalia chebula. It is most often found in leaves)
Hesperetin (flavanone glycoside found abundantly in citrus fruits)
Catechin (a type of natural phenol and antioxidant)
Epigallocatechin gallate (EGCG), also known as epigallocatechin-3-gallate (a potent antioxidant found in green tea)
Xanthohumol (a prenylated chalcone in hops and beer)
Isoxanthohumol (a prenylated flavanone in hops and beer)
Genistein (an isoflavone in soy)
Pro-oxidant flavonoids
Chalconaringenin (a non-prenylated chalcone in citrus fruits)
Naringenin (a non-prenylated flavanone in citrus fruits)
2009 modified Brunswick measuring